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Intel/audio latest fixes #4

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jeromean and others added 30 commits December 12, 2016 17:37
Enable support for HDMI LPE audio mode on Baytrail and
Cherrytrail when HDaudio controller is not detected

Setup minimum required resources during i915_driver_load:
1. Create a platform device to share MMIO/IRQ resources
2. Make the platform device child of i915 device for runtime PM.
3. Create IRQ chip to forward HDMI LPE audio irqs.

HDMI LPE audio driver (a standalone sound driver) probes the
LPE audio device and creates a new sound card.

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Jerome Anand <jerome.anand@intel.com>
Notifiations like mode change, hot plug and edid to
the audio driver are added. This is inturn used by the
audio driver for its functionality.

A new interface file capturing the notifications needed by the
audio driver is added

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Jerome Anand <jerome.anand@intel.com>
On Baytrail and Cherrytrail, HDaudio may be fused out or disabled
by the BIOS. This driver enables an alternate path to the i915
display registers and DMA.

Although there is no hardware path between i915 display and LPE/SST
audio clusters, this HDMI capability is referred to in the documentation
as "HDMI LPE Audio" so we keep the name for consistency. There is no
hardware path or control dependencies with the LPE/SST DSP functionality.

The hdmi-lpe-audio driver will be probed when the i915 driver creates
a child platform device.

Since this driver is neither SoC nor PCI, a new x86 folder is added

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Jerome Anand <jerome.anand@intel.com>
Hdmi audio driver based on the child platform device
created by gfx driver is implemented.
This audio driver is derived from legacy intel
hdmi audio driver.

The interfaces for interaction between gfx and audio
are updated and the driver implementation updated to
derive interrupts in its own address space based on
irq chip framework

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Jerome Anand <jerome.anand@intel.com>
Use a hw register to calculate sub-period position reports.
This makes PulseAudio happier.

Signed-off-by: David Henningsson <david.henningsson@canonical.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Jerome Anand <jerome.anand@intel.com>
This change was given to Canonical apparently to fix an issue with
on some monitor brand. It's not clear what this patch does but it doesn't
seem to have side effects.

Signed-off-by: David Henningsson <david.henningsson@canonical.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Jerome Anand <jerome.anand@intel.com>
When the display resolution changes, the drm disables the
display pipes due to which audio rendering stops. At this
time, we need to ensure the existing audio pointers and
buffers are cleared out so that the playback can restarted
once the display pipe is enabled with a different N/CTS values

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Jerome Anand <jerome.anand@intel.com>
The BayTrail and CherryTrail platforms provide platform clocks
through their Power Management Controller (PMC).

The SoC supports up to 6 clocks (PMC_PLT_CLK[5:0]) with a
frequency of either 19.2 MHz (PLL) or 25 MHz (XTAL) for BayTrail
and a frequency of 19.2 MHz (XTAL) for CherryTrail. These clocks
are available for general system use, where appropriate, and each
have Control & Frequency register fields associated with them.

Signed-off-by: Irina Tirdea <irina.tirdea@intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
The pmc_atom driver does not contain any architecture specific
code. It only enables the SOC Power Management Controller Driver
for BayTrail and CherryTrail platforms.

Move the pmc_atom driver from arch/x86/platform/atom to
drivers/platform/x86.

Signed-off-by: Irina Tirdea <irina.tirdea@intel.com>
The BayTrail and CherryTrail platforms provide platform clocks
through their Power Management Controller (PMC).

The SoC supports up to 6 clocks (PMC_PLT_CLK[5:0]) with a
frequency of either 19.2 MHz (PLL) or 25 MHz (XTAL) for BayTrail
an a frequency of 19.2 MHz (XTAL) for CherryTrail. These clocks
are available for general system use, where appropriate. For example,
the usage for platform clocks suggested in the datasheet is the
following:
  PLT_CLK[2:0] - Camera
  PLT_CLK[3] - Audio Codec
  PLT_CLK[4] -
  PLT_CLK[5] - COMMs

Signed-off-by: Irina Tirdea <irina.tirdea@intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Currently on some headsets slight pops can be heard during DAPM
power-up/down. This can also be witnessed during the HP detect
procedure. This patch addresses the issue by adjusting DAPM power
sequencing slightly, the introduction of delays and use of
minimum HP gain to avoid such noise artefacts.

Signed-off-by: Adam Thomson <Adam.Thomson.Opensource@diasemi.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Add initial setting for rt5663 jd to irq.

Signed-off-by: Jack Yu <jack.yu@realtek.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The "rt5668" codec supported in this driver is actually a revision
of "rt5663". So the patch is renamed to "rt5663 v2"

Signed-off-by: Bard Liao <bardliao@realtek.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
There is a power saving mechanism in rt5660. It will turn off some
unused power when MCLK is not present. We call that "MCLK detection"
and it should be enabled by default.

Signed-off-by: Bard Liao <bardliao@realtek.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Smatch reports below warnings:

    bxt_da7219_max98357a.c:352:9: warning: obsolete array initializer,
    use C99 syntax

An earlier commit cleaned up similar warnings, however, a recent
commit 43c02ed ("ASoC: Intel: Add DMIC channel constraint for
bxt machine") re-introduced the older initializer style. So fix
this warning to make the code consistent.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
There is a power saving mechanism in rt5640. It will turn off some
unused power when MCLK is not present. We call that "MCLK detection"
and it should be enabled by default.

Signed-off-by: Bard Liao <bardliao@realtek.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
There is a power saving mechanism in rt5670. It will turn off some
unused power when MCLK is not present. We call that "MCLK detection"
and it should be enabled by default.

Signed-off-by: Bard Liao <bardliao@realtek.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Check for snd_soc_ops structures that are only stored in the ops field of a
snd_soc_dai_link structure.  This field is declared const, so snd_soc_ops
structures that have this property can be declared as const also.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@r disable optional_qualifier@
identifier i;
position p;
@@
static struct snd_soc_ops i@p = { ... };

@ok1@
identifier r.i;
struct snd_soc_dai_link e;
position p;
@@
e.ops = &i@p;

@ok2@
identifier r.i, e;
position p;
@@
struct snd_soc_dai_link e[] = { ..., { .ops = &i@p, }, ..., };

@bad@
position p != {r.p,ok1.p,ok2.p};
identifier r.i;
struct snd_soc_ops e;
@@
e@i@p

@Depends on !bad disable optional_qualifier@
identifier r.i;
@@
static
+const
 struct snd_soc_ops i = { ... };
// </smpl>

The effect on the layout of the .o file is shown by the following output of
the size command, first before then after the transformation:

   text    data     bss     dec     hex filename
   3865    2784     384    7033    1b79 sound/soc/intel/boards/broadwell.o
   3929    2720     384    7033    1b79 sound/soc/intel/boards/broadwell.o

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Acked-by: Jie Yang <yang.jie@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Check for snd_soc_ops structures that are only stored in the ops field of a
snd_soc_dai_link structure.  This field is declared const, so snd_soc_ops
structures that have this property can be declared as const also.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@r disable optional_qualifier@
identifier i;
position p;
@@
static struct snd_soc_ops i@p = { ... };

@ok1@
identifier r.i;
struct snd_soc_dai_link e;
position p;
@@
e.ops = &i@p;

@ok2@
identifier r.i, e;
position p;
@@
struct snd_soc_dai_link e[] = { ..., { .ops = &i@p, }, ..., };

@bad@
position p != {r.p,ok1.p,ok2.p};
identifier r.i;
struct snd_soc_ops e;
@@
e@i@p

@Depends on !bad disable optional_qualifier@
identifier r.i;
@@
static
+const
 struct snd_soc_ops i = { ... };
// </smpl>

The effect on the layout of the .o files is shown by the following output
of the size command, first before then after the transformation:

   text    data     bss     dec     hex filename
   4500     696       0    5196    144c sound/soc/generic/simple-card.o
   4564     632       0    5196    144c sound/soc/generic/simple-card.o

   text    data     bss     dec     hex filename
   3018     608       0    3626     e2a sound/soc/generic/simple-scu-card.o
   3074     544       0    3618     e22 sound/soc/generic/simple-scu-card.o

   text    data     bss     dec     hex filename
   4148    2448     768    7364    1cc4 sound/soc/intel/boards/bdw-rt5677.o
   4212    2384     768    7364    1cc4 sound/soc/intel/boards/bdw-rt5677.o

   text    data     bss     dec     hex filename
   5403    4628     384   10415    28af sound/soc/intel/boards/bxt_da7219_max98357a.o
   5531    4516     384   10431    28bf sound/soc/intel/boards/bxt_da7219_max98357a.o

   text    data     bss     dec     hex filename
   5275    4496     384   10155    27ab sound/soc/intel/boards/bxt_rt298.o
   5403    4368     384   10155    27ab sound/soc/intel/boards/bxt_rt298.o

   text    data     bss     dec     hex filename
  10017    2344      48   12409    3079 sound/soc/intel/boards/bytcr_rt5640.o
  10145    2232      48   12425    3089 sound/soc/intel/boards/bytcr_rt5640.o

   text    data     bss     dec     hex filename
   3719    2356       0    6075    17bb sound/soc/intel/boards/bytcr_rt5651.o
   3847    2244       0    6091    17cb sound/soc/intel/boards/bytcr_rt5651.o

   text    data     bss     dec     hex filename
   3598    2392       0    5990    1766 sound/soc/intel/boards/cht_bsw_max98090_ti.o
   3726    2280       0    6006    1776 sound/soc/intel/boards/cht_bsw_max98090_ti.o

   text    data     bss     dec     hex filename
   5343    3624      16    8983    2317 sound/soc/intel/boards/cht_bsw_rt5645.o
   5471    3496      16    8983    2317 sound/soc/intel/boards/cht_bsw_rt5645.o

   text    data     bss     dec     hex filename
   4662    2592     384    7638    1dd6 sound/soc/intel/boards/cht_bsw_rt5672.o
   4790    2464     384    7638    1dd6 sound/soc/intel/boards/cht_bsw_rt5672.o

   text    data     bss     dec     hex filename
   1595    2528       0    4123    101b sound/soc/intel/boards/haswell.o
   1659    2472       0    4131    1023 sound/soc/intel/boards/haswell.o

   text    data     bss     dec     hex filename
   6272    4760     416   11448    2cb8 sound/soc/intel/boards/skl_nau88l25_max98357a.o
   6464    4568     416   11448    2cb8 sound/soc/intel/boards/skl_nau88l25_max98357a.o

   text    data     bss     dec     hex filename
   7075    4888     416   12379    305b sound/soc/intel/boards/skl_nau88l25_ssm4567.o
   7267    4696     416   12379    305b sound/soc/intel/boards/skl_nau88l25_ssm4567.o

   text    data     bss     dec     hex filename
   5659    4496     384   10539    292b sound/soc/intel/boards/skl_rt286.o
   5787    4368     384   10539    292b sound/soc/intel/boards/skl_rt286.o

   text    data     bss     dec     hex filename
   1721    2048       0    3769     eb9 sound/soc/kirkwood/armada-370-db.o
   1769    1976       0    3745     ea1 sound/soc/kirkwood/armada-370-db.o

   text    data     bss     dec     hex filename
   1363    1792       0    3155     c53 sound/soc/mxs/mxs-sgtl5000.o
   1427    1728       0    3155     c53 sound/soc/mxs/mxs-sgtl5000.o

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Mark Brown <broonie@kernel.org>
"*val" is a u64.  It definitely looks like we intend to use the high 32
bits as well.

Fixes: 700a9a6 ("ASoC: Intel: Skylake: Add module instance id generation APIs")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Tested-by: Kranthi G <gudishax.kranthikumar@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Inrecse LDO power for better performance.

Signed-off-by: Bard Liao <bardliao@realtek.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
DPIB is read currently from a buffer position in memory (indicated by
the registers DPIB[U|L]BASE).Driver reads the position buffer on BDL
completion interrupts to report the DMA position. But the BDL completion
interrupt only indicates the last DMA transfer of the buffer is
completed at the Intel HD Audio subsystem boundary. The periodic DMA
Position-in-Buffer writes may be scheduled at the same time or later
than the MSI and does not guarantee to reflect the position of the last
buffer that was transferred.

Whereas DPIB register in HDA space(vendor specific register indicated by
SDxDPIB) reflects the actual data that is transferred. Hence update the
position based on DPIB for playback.

Signed-off-by: Dharageswari R <dharageswari.r@intel.com>
Signed-off-by: Jeeja KP <jeeja.kp@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This patch is adding debug information related to SST FW version.

Signed-off-by: Sebastien Guiriec <sebastien.guiriec@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Some controllers support power modes which can't communicate using IPC.

So add a callback to check and wake DSP before sending IPC and then put
to sleep if it is in these power modes.

Signed-off-by: Jayachandran B <jayachandran.b@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Mono ADC Capture Switch control is missing in the driver. So, add it.

Signed-off-by: Bard Liao <bardliao@realtek.com>
Tested-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
If the DSP is in low power mode, it needs to be woken up by a "wake" IPC
to set it into the D0 state before we can send any other IPC command.

The call flow is that the driver calls sst_ipc_tx_message_wait() to send any
IPC and this call checks if the device is in low power mode and in that
case we need to send the wake IPC.

So add a new IPC nopm variant which can be called from driver and
doesn't check for power state (as we already know that) and avoids
circular dependency of again checking power state.

Signed-off-by: Jayachandran B <jayachandran.b@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The audio DSP supports intermediate power states between D0 and D3
states. These states are D0i0 and D0i3 states.

Collectively we refer these two states as D0iX states.

To set or wake up from these states, driver also needs to send an IPC "Set D0iX
IPC" before doing anything else.

Add support for this new IPC messages.

Signed-off-by: Pardha Saradhi K <pardha.saradhi.kesapragada@intel.com>
Signed-off-by: Jayachandran B <jayachandran.b@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
To set the controller in D0i3 mode, the driver needs to set D0i3C
register after DSP is quiesced. Since the D0iX entry/exit is done by IPC,
add this as callback so that it can be invoked from IPC module.

Signed-off-by: Pardha Saradhi K <pardha.saradhi.kesapragada@intel.com>
Signed-off-by: Jayachandran B <jayachandran.b@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The driver needs two DSP callback, one to set D0i0 (active) and D0i3
(low-power) states.

Add these callbacks in dsp ops and implement them for broxton platforms.

Signed-off-by: Jayachandran B <jayachandran.b@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
For D0i3, we need to tell DSP to run the pipelines in LP mode. This
information is kept in topology and passed to driver as an attribute
for pipe.

So add a new tuple for lpmode and program the pipe based on value set.

Signed-off-by: Jayachandran B <jayachandran.b@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
tiwai pushed a commit that referenced this pull request May 3, 2024
…git/netfilter/nf

netfilter pull request 24-04-11

Pablo Neira Ayuso says:

====================
Netfilter fixes for net

The following patchset contains Netfilter fixes for net:

Patches #1 and #2 add missing rcu read side lock when iterating over
expression and object type list which could race with module removal.

Patch #3 prevents promisc packet from visiting the bridge/input hook
	 to amend a recent fix to address conntrack confirmation race
	 in br_netfilter and nf_conntrack_bridge.

Patch #4 adds and uses iterate decorator type to fetch the current
	 pipapo set backend datastructure view when netlink dumps the
	 set elements.

Patch #5 fixes removal of duplicate elements in the pipapo set backend.

Patch #6 flowtable validates pppoe header before accessing it.

Patch #7 fixes flowtable datapath for pppoe packets, otherwise lookup
         fails and pppoe packets follow classic path.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
tiwai pushed a commit that referenced this pull request May 3, 2024
When I did hard offline test with hugetlb pages, below deadlock occurs:

======================================================
WARNING: possible circular locking dependency detected
6.8.0-11409-gf6cef5f8c37f #1 Not tainted
------------------------------------------------------
bash/46904 is trying to acquire lock:
ffffffffabe68910 (cpu_hotplug_lock){++++}-{0:0}, at: static_key_slow_dec+0x16/0x60

but task is already holding lock:
ffffffffabf92ea8 (pcp_batch_high_lock){+.+.}-{3:3}, at: zone_pcp_disable+0x16/0x40

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 (pcp_batch_high_lock){+.+.}-{3:3}:
       __mutex_lock+0x6c/0x770
       page_alloc_cpu_online+0x3c/0x70
       cpuhp_invoke_callback+0x397/0x5f0
       __cpuhp_invoke_callback_range+0x71/0xe0
       _cpu_up+0xeb/0x210
       cpu_up+0x91/0xe0
       cpuhp_bringup_mask+0x49/0xb0
       bringup_nonboot_cpus+0xb7/0xe0
       smp_init+0x25/0xa0
       kernel_init_freeable+0x15f/0x3e0
       kernel_init+0x15/0x1b0
       ret_from_fork+0x2f/0x50
       ret_from_fork_asm+0x1a/0x30

-> #0 (cpu_hotplug_lock){++++}-{0:0}:
       __lock_acquire+0x1298/0x1cd0
       lock_acquire+0xc0/0x2b0
       cpus_read_lock+0x2a/0xc0
       static_key_slow_dec+0x16/0x60
       __hugetlb_vmemmap_restore_folio+0x1b9/0x200
       dissolve_free_huge_page+0x211/0x260
       __page_handle_poison+0x45/0xc0
       memory_failure+0x65e/0xc70
       hard_offline_page_store+0x55/0xa0
       kernfs_fop_write_iter+0x12c/0x1d0
       vfs_write+0x387/0x550
       ksys_write+0x64/0xe0
       do_syscall_64+0xca/0x1e0
       entry_SYSCALL_64_after_hwframe+0x6d/0x75

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(pcp_batch_high_lock);
                               lock(cpu_hotplug_lock);
                               lock(pcp_batch_high_lock);
  rlock(cpu_hotplug_lock);

 *** DEADLOCK ***

5 locks held by bash/46904:
 #0: ffff98f6c3bb23f0 (sb_writers#5){.+.+}-{0:0}, at: ksys_write+0x64/0xe0
 #1: ffff98f6c328e488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0xf8/0x1d0
 #2: ffff98ef83b31890 (kn->active#113){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x100/0x1d0
 #3: ffffffffabf9db48 (mf_mutex){+.+.}-{3:3}, at: memory_failure+0x44/0xc70
 #4: ffffffffabf92ea8 (pcp_batch_high_lock){+.+.}-{3:3}, at: zone_pcp_disable+0x16/0x40

stack backtrace:
CPU: 10 PID: 46904 Comm: bash Kdump: loaded Not tainted 6.8.0-11409-gf6cef5f8c37f #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x68/0xa0
 check_noncircular+0x129/0x140
 __lock_acquire+0x1298/0x1cd0
 lock_acquire+0xc0/0x2b0
 cpus_read_lock+0x2a/0xc0
 static_key_slow_dec+0x16/0x60
 __hugetlb_vmemmap_restore_folio+0x1b9/0x200
 dissolve_free_huge_page+0x211/0x260
 __page_handle_poison+0x45/0xc0
 memory_failure+0x65e/0xc70
 hard_offline_page_store+0x55/0xa0
 kernfs_fop_write_iter+0x12c/0x1d0
 vfs_write+0x387/0x550
 ksys_write+0x64/0xe0
 do_syscall_64+0xca/0x1e0
 entry_SYSCALL_64_after_hwframe+0x6d/0x75
RIP: 0033:0x7fc862314887
Code: 10 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 48 89 54 24 18 48 89 74 24
RSP: 002b:00007fff19311268 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000000000000000c RCX: 00007fc862314887
RDX: 000000000000000c RSI: 000056405645fe10 RDI: 0000000000000001
RBP: 000056405645fe10 R08: 00007fc8623d1460 R09: 000000007fffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000000c
R13: 00007fc86241b780 R14: 00007fc862417600 R15: 00007fc862416a00

In short, below scene breaks the lock dependency chain:

 memory_failure
  __page_handle_poison
   zone_pcp_disable -- lock(pcp_batch_high_lock)
   dissolve_free_huge_page
    __hugetlb_vmemmap_restore_folio
     static_key_slow_dec
      cpus_read_lock -- rlock(cpu_hotplug_lock)

Fix this by calling drain_all_pages() instead.

This issue won't occur until commit a6b4085 ("mm: hugetlb: replace
hugetlb_free_vmemmap_enabled with a static_key").  As it introduced
rlock(cpu_hotplug_lock) in dissolve_free_huge_page() code path while
lock(pcp_batch_high_lock) is already in the __page_handle_poison().

[linmiaohe@huawei.com: extend comment per Oscar]
[akpm@linux-foundation.org: reflow block comment]
Link: https://lkml.kernel.org/r/20240407085456.2798193-1-linmiaohe@huawei.com
Fixes: a6b4085 ("mm: hugetlb: replace hugetlb_free_vmemmap_enabled with a static_key")
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Acked-by: Oscar Salvador <osalvador@suse.de>
Reviewed-by: Jane Chu <jane.chu@oracle.com>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
tiwai pushed a commit that referenced this pull request May 3, 2024
vhost_worker will call tun call backs to receive packets. If too many
illegal packets arrives, tun_do_read will keep dumping packet contents.
When console is enabled, it will costs much more cpu time to dump
packet and soft lockup will be detected.

net_ratelimit mechanism can be used to limit the dumping rate.

PID: 33036    TASK: ffff949da6f20000  CPU: 23   COMMAND: "vhost-32980"
 #0 [fffffe00003fce50] crash_nmi_callback at ffffffff89249253
 #1 [fffffe00003fce58] nmi_handle at ffffffff89225fa3
 #2 [fffffe00003fceb0] default_do_nmi at ffffffff8922642e
 #3 [fffffe00003fced0] do_nmi at ffffffff8922660d
 #4 [fffffe00003fcef0] end_repeat_nmi at ffffffff89c01663
    [exception RIP: io_serial_in+20]
    RIP: ffffffff89792594  RSP: ffffa655314979e8  RFLAGS: 00000002
    RAX: ffffffff89792500  RBX: ffffffff8af428a0  RCX: 0000000000000000
    RDX: 00000000000003fd  RSI: 0000000000000005  RDI: ffffffff8af428a0
    RBP: 0000000000002710   R8: 0000000000000004   R9: 000000000000000f
    R10: 0000000000000000  R11: ffffffff8acbf64f  R12: 0000000000000020
    R13: ffffffff8acbf698  R14: 0000000000000058  R15: 0000000000000000
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 #5 [ffffa655314979e8] io_serial_in at ffffffff89792594
 #6 [ffffa655314979e8] wait_for_xmitr at ffffffff89793470
 #7 [ffffa65531497a08] serial8250_console_putchar at ffffffff897934f6
 torvalds#8 [ffffa65531497a20] uart_console_write at ffffffff8978b605
 torvalds#9 [ffffa65531497a48] serial8250_console_write at ffffffff89796558
 torvalds#10 [ffffa65531497ac8] console_unlock at ffffffff89316124
 torvalds#11 [ffffa65531497b10] vprintk_emit at ffffffff89317c07
 torvalds#12 [ffffa65531497b68] printk at ffffffff89318306
 torvalds#13 [ffffa65531497bc8] print_hex_dump at ffffffff89650765
 torvalds#14 [ffffa65531497ca8] tun_do_read at ffffffffc0b06c27 [tun]
 torvalds#15 [ffffa65531497d38] tun_recvmsg at ffffffffc0b06e34 [tun]
 torvalds#16 [ffffa65531497d68] handle_rx at ffffffffc0c5d682 [vhost_net]
 torvalds#17 [ffffa65531497ed0] vhost_worker at ffffffffc0c644dc [vhost]
 torvalds#18 [ffffa65531497f10] kthread at ffffffff892d2e72
 torvalds#19 [ffffa65531497f50] ret_from_fork at ffffffff89c0022f

Fixes: ef3db4a ("tun: avoid BUG, dump packet on GSO errors")
Signed-off-by: Lei Chen <lei.chen@smartx.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Link: https://lore.kernel.org/r/20240415020247.2207781-1-lei.chen@smartx.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
tiwai pushed a commit that referenced this pull request May 27, 2024
…rnel/git/netfilter/nf-next

Pablo Neira Ayuso says:

====================
Netfilter updates for net-next

The following patchset contains Netfilter updates for net-next:

Patch #1 skips transaction if object type provides no .update interface.

Patch #2 skips NETDEV_CHANGENAME which is unused.

Patch #3 enables conntrack to handle Multicast Router Advertisements and
	 Multicast Router Solicitations from the Multicast Router Discovery
	 protocol (RFC4286) as untracked opposed to invalid packets.
	 From Linus Luessing.

Patch #4 updates DCCP conntracker to mark invalid as invalid, instead of
	 dropping them, from Jason Xing.

Patch #5 uses NF_DROP instead of -NF_DROP since NF_DROP is 0,
	 also from Jason.

Patch #6 removes reference in netfilter's sysctl documentation on pickup
	 entries which were already removed by Florian Westphal.

Patch #7 removes check for IPS_OFFLOAD flag to disable early drop which
	 allows to evict entries from the conntrack table,
	 also from Florian.

Patches torvalds#8 to torvalds#16 updates nf_tables pipapo set backend to allocate
	 the datastructure copy on-demand from preparation phase,
	 to better deal with OOM situations where .commit step is too late
	 to fail. Series from Florian Westphal.

Patch torvalds#17 adds a selftest with packetdrill to cover conntrack TCP state
	 transitions, also from Florian.

Patch torvalds#18 use GFP_KERNEL to clone elements from control plane to avoid
	 quick atomic reserves exhaustion with large sets, reporter refers
	 to million entries magnitude.

* tag 'nf-next-24-05-12' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next:
  netfilter: nf_tables: allow clone callbacks to sleep
  selftests: netfilter: add packetdrill based conntrack tests
  netfilter: nft_set_pipapo: remove dirty flag
  netfilter: nft_set_pipapo: move cloning of match info to insert/removal path
  netfilter: nft_set_pipapo: prepare pipapo_get helper for on-demand clone
  netfilter: nft_set_pipapo: merge deactivate helper into caller
  netfilter: nft_set_pipapo: prepare walk function for on-demand clone
  netfilter: nft_set_pipapo: prepare destroy function for on-demand clone
  netfilter: nft_set_pipapo: make pipapo_clone helper return NULL
  netfilter: nft_set_pipapo: move prove_locking helper around
  netfilter: conntrack: remove flowtable early-drop test
  netfilter: conntrack: documentation: remove reference to non-existent sysctl
  netfilter: use NF_DROP instead of -NF_DROP
  netfilter: conntrack: dccp: try not to drop skb in conntrack
  netfilter: conntrack: fix ct-state for ICMPv6 Multicast Router Discovery
  netfilter: nf_tables: remove NETDEV_CHANGENAME from netdev chain event handler
  netfilter: nf_tables: skip transaction if update object is not implemented
====================

Link: https://lore.kernel.org/r/20240512161436.168973-1-pablo@netfilter.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
tiwai pushed a commit that referenced this pull request Jun 26, 2024
…git/netfilter/nf

Pablo Neira Ayuso says:

====================
Netfilter fixes for net

The following patchset contains Netfilter fixes for net:

Patch #1 syzbot reports that nf_reinject() could be called without
         rcu_read_lock() when flushing pending packets at nfnetlink
         queue removal, from Eric Dumazet.

Patch #2 flushes ipset list:set when canceling garbage collection to
         reference to other lists to fix a race, from Jozsef Kadlecsik.

Patch #3 restores q-in-q matching with nft_payload by reverting
         f6ae9f1 ("netfilter: nft_payload: add C-VLAN support").

Patch #4 fixes vlan mangling in skbuff when vlan offload is present
         in skbuff, without this patch nft_payload corrupts packets
         in this case.

Patch #5 fixes possible nul-deref in tproxy no IP address is found in
         netdevice, reported by syzbot and patch from Florian Westphal.

Patch #6 removes a superfluous restriction which prevents loose fib
         lookups from input and forward hooks, from Eric Garver.

My assessment is that patches #1, #2 and #5 address possible kernel
crash, anything else in this batch fixes broken features.

netfilter pull request 24-05-29

* tag 'nf-24-05-29' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf:
  netfilter: nft_fib: allow from forward/input without iif selector
  netfilter: tproxy: bail out if IP has been disabled on the device
  netfilter: nft_payload: skbuff vlan metadata mangle support
  netfilter: nft_payload: restore vlan q-in-q match support
  netfilter: ipset: Add list flush to cancel_gc
  netfilter: nfnetlink_queue: acquire rcu_read_lock() in instance_destroy_rcu()
====================

Link: https://lore.kernel.org/r/20240528225519.1155786-1-pablo@netfilter.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
tiwai pushed a commit that referenced this pull request Jun 27, 2024
With commit c4cb231 ("iommu/amd: Add support for enable/disable IOPF")
we are hitting below issue. This happens because in IOPF enablement path
it holds spin lock with irq disable and then tries to take mutex lock.

dmesg:
-----
[    0.938739] =============================
[    0.938740] [ BUG: Invalid wait context ]
[    0.938742] 6.10.0-rc1+ #1 Not tainted
[    0.938745] -----------------------------
[    0.938746] swapper/0/1 is trying to lock:
[    0.938748] ffffffff8c9f01d8 (&port_lock_key){....}-{3:3}, at: serial8250_console_write+0x78/0x4a0
[    0.938767] other info that might help us debug this:
[    0.938768] context-{5:5}
[    0.938769] 7 locks held by swapper/0/1:
[    0.938772]  #0: ffff888101a91310 (&group->mutex){+.+.}-{4:4}, at: bus_iommu_probe+0x70/0x160
[    0.938790]  #1: ffff888101d1f1b8 (&domain->lock){....}-{3:3}, at: amd_iommu_attach_device+0xa5/0x700
[    0.938799]  #2: ffff888101cc3d18 (&dev_data->lock){....}-{3:3}, at: amd_iommu_attach_device+0xc5/0x700
[    0.938806]  #3: ffff888100052830 (&iommu->lock){....}-{2:2}, at: amd_iommu_iopf_add_device+0x3f/0xa0
[    0.938813]  #4: ffffffff8945a340 (console_lock){+.+.}-{0:0}, at: _printk+0x48/0x50
[    0.938822]  #5: ffffffff8945a390 (console_srcu){....}-{0:0}, at: console_flush_all+0x58/0x4e0
[    0.938867]  #6: ffffffff82459f80 (console_owner){....}-{0:0}, at: console_flush_all+0x1f0/0x4e0
[    0.938872] stack backtrace:
[    0.938874] CPU: 2 PID: 1 Comm: swapper/0 Not tainted 6.10.0-rc1+ #1
[    0.938877] Hardware name: HP HP EliteBook 745 G3/807E, BIOS N73 Ver. 01.39 04/16/2019

Fix above issue by re-arranging code in attach device path:
  - move device PASID/IOPF enablement outside lock in AMD IOMMU driver.
    This is safe as core layer holds group->mutex lock before calling
    iommu_ops->attach_dev.

Reported-by: Borislav Petkov <bp@alien8.de>
Reported-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com>
Reported-by: Chris Bainbridge <chris.bainbridge@gmail.com>
Fixes: c4cb231 ("iommu/amd: Add support for enable/disable IOPF")
Tested-by: Borislav Petkov <bp@alien8.de>
Tested-by: Chris Bainbridge <chris.bainbridge@gmail.com>
Tested-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com>
Signed-off-by: Vasant Hegde <vasant.hegde@amd.com>
Link: https://lore.kernel.org/r/20240530084801.10758-1-vasant.hegde@amd.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
tiwai pushed a commit that referenced this pull request Jun 27, 2024
…PLES event"

This reverts commit 7d1405c.

This causes segfaults in some cases, as reported by Milian:

  ```
  sudo /usr/bin/perf record -z --call-graph dwarf -e cycles -e
  raw_syscalls:sys_enter ls
  ...
  [ perf record: Woken up 3 times to write data ]
  malloc(): invalid next size (unsorted)
  Aborted
  ```

  Backtrace with GDB + debuginfod:

  ```
  malloc(): invalid next size (unsorted)

  Thread 1 "perf" received signal SIGABRT, Aborted.
  __pthread_kill_implementation (threadid=<optimized out>, signo=signo@entry=6,
  no_tid=no_tid@entry=0) at pthread_kill.c:44
  Downloading source file /usr/src/debug/glibc/glibc/nptl/pthread_kill.c
  44            return INTERNAL_SYSCALL_ERROR_P (ret) ? INTERNAL_SYSCALL_ERRNO
  (ret) : 0;
  (gdb) bt
  #0  __pthread_kill_implementation (threadid=<optimized out>,
  signo=signo@entry=6, no_tid=no_tid@entry=0) at pthread_kill.c:44
  #1  0x00007ffff6ea8eb3 in __pthread_kill_internal (threadid=<optimized out>,
  signo=6) at pthread_kill.c:78
  #2  0x00007ffff6e50a30 in __GI_raise (sig=sig@entry=6) at ../sysdeps/posix/
  raise.c:26
  #3  0x00007ffff6e384c3 in __GI_abort () at abort.c:79
  #4  0x00007ffff6e39354 in __libc_message_impl (fmt=fmt@entry=0x7ffff6fc22ea
  "%s\n") at ../sysdeps/posix/libc_fatal.c:132
  #5  0x00007ffff6eb3085 in malloc_printerr (str=str@entry=0x7ffff6fc5850
  "malloc(): invalid next size (unsorted)") at malloc.c:5772
  #6  0x00007ffff6eb657c in _int_malloc (av=av@entry=0x7ffff6ff6ac0
  <main_arena>, bytes=bytes@entry=368) at malloc.c:4081
  #7  0x00007ffff6eb877e in __libc_calloc (n=<optimized out>,
  elem_size=<optimized out>) at malloc.c:3754
  torvalds#8  0x000055555569bdb6 in perf_session.do_write_header ()
  torvalds#9  0x00005555555a373a in __cmd_record.constprop.0 ()
  torvalds#10 0x00005555555a6846 in cmd_record ()
  torvalds#11 0x000055555564db7f in run_builtin ()
  torvalds#12 0x000055555558ed77 in main ()
  ```

  Valgrind memcheck:
  ```
  ==45136== Invalid write of size 8
  ==45136==    at 0x2B38A5: perf_event__synthesize_id_sample (in /usr/bin/perf)
  ==45136==    by 0x157069: __cmd_record.constprop.0 (in /usr/bin/perf)
  ==45136==    by 0x15A845: cmd_record (in /usr/bin/perf)
  ==45136==    by 0x201B7E: run_builtin (in /usr/bin/perf)
  ==45136==    by 0x142D76: main (in /usr/bin/perf)
  ==45136==  Address 0x6a866a8 is 0 bytes after a block of size 40 alloc'd
  ==45136==    at 0x4849BF3: calloc (vg_replace_malloc.c:1675)
  ==45136==    by 0x3574AB: zalloc (in /usr/bin/perf)
  ==45136==    by 0x1570E0: __cmd_record.constprop.0 (in /usr/bin/perf)
  ==45136==    by 0x15A845: cmd_record (in /usr/bin/perf)
  ==45136==    by 0x201B7E: run_builtin (in /usr/bin/perf)
  ==45136==    by 0x142D76: main (in /usr/bin/perf)
  ==45136==
  ==45136== Syscall param write(buf) points to unaddressable byte(s)
  ==45136==    at 0x575953D: __libc_write (write.c:26)
  ==45136==    by 0x575953D: write (write.c:24)
  ==45136==    by 0x35761F: ion (in /usr/bin/perf)
  ==45136==    by 0x357778: writen (in /usr/bin/perf)
  ==45136==    by 0x1548F7: record__write (in /usr/bin/perf)
  ==45136==    by 0x15708A: __cmd_record.constprop.0 (in /usr/bin/perf)
  ==45136==    by 0x15A845: cmd_record (in /usr/bin/perf)
  ==45136==    by 0x201B7E: run_builtin (in /usr/bin/perf)
  ==45136==    by 0x142D76: main (in /usr/bin/perf)
  ==45136==  Address 0x6a866a8 is 0 bytes after a block of size 40 alloc'd
  ==45136==    at 0x4849BF3: calloc (vg_replace_malloc.c:1675)
  ==45136==    by 0x3574AB: zalloc (in /usr/bin/perf)
  ==45136==    by 0x1570E0: __cmd_record.constprop.0 (in /usr/bin/perf)
  ==45136==    by 0x15A845: cmd_record (in /usr/bin/perf)
  ==45136==    by 0x201B7E: run_builtin (in /usr/bin/perf)
  ==45136==    by 0x142D76: main (in /usr/bin/perf)
  ==45136==
 -----

Closes: https://lore.kernel.org/linux-perf-users/23879991.0LEYPuXRzz@milian-workstation/
Reported-by: Milian Wolff <milian.wolff@kdab.com>
Tested-by: Milian Wolff <milian.wolff@kdab.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: stable@kernel.org # 6.8+
Link: https://lore.kernel.org/lkml/Zl9ksOlHJHnKM70p@x1
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
tiwai pushed a commit that referenced this pull request Jun 27, 2024
We have been seeing crashes on duplicate keys in
btrfs_set_item_key_safe():

  BTRFS critical (device vdb): slot 4 key (450 108 8192) new key (450 108 8192)
  ------------[ cut here ]------------
  kernel BUG at fs/btrfs/ctree.c:2620!
  invalid opcode: 0000 [#1] PREEMPT SMP PTI
  CPU: 0 PID: 3139 Comm: xfs_io Kdump: loaded Not tainted 6.9.0 #6
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-2.fc40 04/01/2014
  RIP: 0010:btrfs_set_item_key_safe+0x11f/0x290 [btrfs]

With the following stack trace:

  #0  btrfs_set_item_key_safe (fs/btrfs/ctree.c:2620:4)
  #1  btrfs_drop_extents (fs/btrfs/file.c:411:4)
  #2  log_one_extent (fs/btrfs/tree-log.c:4732:9)
  #3  btrfs_log_changed_extents (fs/btrfs/tree-log.c:4955:9)
  #4  btrfs_log_inode (fs/btrfs/tree-log.c:6626:9)
  #5  btrfs_log_inode_parent (fs/btrfs/tree-log.c:7070:8)
  #6  btrfs_log_dentry_safe (fs/btrfs/tree-log.c:7171:8)
  #7  btrfs_sync_file (fs/btrfs/file.c:1933:8)
  torvalds#8  vfs_fsync_range (fs/sync.c:188:9)
  torvalds#9  vfs_fsync (fs/sync.c:202:9)
  torvalds#10 do_fsync (fs/sync.c:212:9)
  torvalds#11 __do_sys_fdatasync (fs/sync.c:225:9)
  torvalds#12 __se_sys_fdatasync (fs/sync.c:223:1)
  torvalds#13 __x64_sys_fdatasync (fs/sync.c:223:1)
  torvalds#14 do_syscall_x64 (arch/x86/entry/common.c:52:14)
  torvalds#15 do_syscall_64 (arch/x86/entry/common.c:83:7)
  torvalds#16 entry_SYSCALL_64+0xaf/0x14c (arch/x86/entry/entry_64.S:121)

So we're logging a changed extent from fsync, which is splitting an
extent in the log tree. But this split part already exists in the tree,
triggering the BUG().

This is the state of the log tree at the time of the crash, dumped with
drgn (https://github.com/osandov/drgn/blob/main/contrib/btrfs_tree.py)
to get more details than btrfs_print_leaf() gives us:

  >>> print_extent_buffer(prog.crashed_thread().stack_trace()[0]["eb"])
  leaf 33439744 level 0 items 72 generation 9 owner 18446744073709551610
  leaf 33439744 flags 0x100000000000000
  fs uuid e5bd3946-400c-4223-8923-190ef1f18677
  chunk uuid d58cb17e-6d02-494a-829a-18b7d8a399da
          item 0 key (450 INODE_ITEM 0) itemoff 16123 itemsize 160
                  generation 7 transid 9 size 8192 nbytes 8473563889606862198
                  block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0
                  sequence 204 flags 0x10(PREALLOC)
                  atime 1716417703.220000000 (2024-05-22 15:41:43)
                  ctime 1716417704.983333333 (2024-05-22 15:41:44)
                  mtime 1716417704.983333333 (2024-05-22 15:41:44)
                  otime 17592186044416.000000000 (559444-03-08 01:40:16)
          item 1 key (450 INODE_REF 256) itemoff 16110 itemsize 13
                  index 195 namelen 3 name: 193
          item 2 key (450 XATTR_ITEM 1640047104) itemoff 16073 itemsize 37
                  location key (0 UNKNOWN.0 0) type XATTR
                  transid 7 data_len 1 name_len 6
                  name: user.a
                  data a
          item 3 key (450 EXTENT_DATA 0) itemoff 16020 itemsize 53
                  generation 9 type 1 (regular)
                  extent data disk byte 303144960 nr 12288
                  extent data offset 0 nr 4096 ram 12288
                  extent compression 0 (none)
          item 4 key (450 EXTENT_DATA 4096) itemoff 15967 itemsize 53
                  generation 9 type 2 (prealloc)
                  prealloc data disk byte 303144960 nr 12288
                  prealloc data offset 4096 nr 8192
          item 5 key (450 EXTENT_DATA 8192) itemoff 15914 itemsize 53
                  generation 9 type 2 (prealloc)
                  prealloc data disk byte 303144960 nr 12288
                  prealloc data offset 8192 nr 4096
  ...

So the real problem happened earlier: notice that items 4 (4k-12k) and 5
(8k-12k) overlap. Both are prealloc extents. Item 4 straddles i_size and
item 5 starts at i_size.

Here is the state of the filesystem tree at the time of the crash:

  >>> root = prog.crashed_thread().stack_trace()[2]["inode"].root
  >>> ret, nodes, slots = btrfs_search_slot(root, BtrfsKey(450, 0, 0))
  >>> print_extent_buffer(nodes[0])
  leaf 30425088 level 0 items 184 generation 9 owner 5
  leaf 30425088 flags 0x100000000000000
  fs uuid e5bd3946-400c-4223-8923-190ef1f18677
  chunk uuid d58cb17e-6d02-494a-829a-18b7d8a399da
  	...
          item 179 key (450 INODE_ITEM 0) itemoff 4907 itemsize 160
                  generation 7 transid 7 size 4096 nbytes 12288
                  block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0
                  sequence 6 flags 0x10(PREALLOC)
                  atime 1716417703.220000000 (2024-05-22 15:41:43)
                  ctime 1716417703.220000000 (2024-05-22 15:41:43)
                  mtime 1716417703.220000000 (2024-05-22 15:41:43)
                  otime 1716417703.220000000 (2024-05-22 15:41:43)
          item 180 key (450 INODE_REF 256) itemoff 4894 itemsize 13
                  index 195 namelen 3 name: 193
          item 181 key (450 XATTR_ITEM 1640047104) itemoff 4857 itemsize 37
                  location key (0 UNKNOWN.0 0) type XATTR
                  transid 7 data_len 1 name_len 6
                  name: user.a
                  data a
          item 182 key (450 EXTENT_DATA 0) itemoff 4804 itemsize 53
                  generation 9 type 1 (regular)
                  extent data disk byte 303144960 nr 12288
                  extent data offset 0 nr 8192 ram 12288
                  extent compression 0 (none)
          item 183 key (450 EXTENT_DATA 8192) itemoff 4751 itemsize 53
                  generation 9 type 2 (prealloc)
                  prealloc data disk byte 303144960 nr 12288
                  prealloc data offset 8192 nr 4096

Item 5 in the log tree corresponds to item 183 in the filesystem tree,
but nothing matches item 4. Furthermore, item 183 is the last item in
the leaf.

btrfs_log_prealloc_extents() is responsible for logging prealloc extents
beyond i_size. It first truncates any previously logged prealloc extents
that start beyond i_size. Then, it walks the filesystem tree and copies
the prealloc extent items to the log tree.

If it hits the end of a leaf, then it calls btrfs_next_leaf(), which
unlocks the tree and does another search. However, while the filesystem
tree is unlocked, an ordered extent completion may modify the tree. In
particular, it may insert an extent item that overlaps with an extent
item that was already copied to the log tree.

This may manifest in several ways depending on the exact scenario,
including an EEXIST error that is silently translated to a full sync,
overlapping items in the log tree, or this crash. This particular crash
is triggered by the following sequence of events:

- Initially, the file has i_size=4k, a regular extent from 0-4k, and a
  prealloc extent beyond i_size from 4k-12k. The prealloc extent item is
  the last item in its B-tree leaf.
- The file is fsync'd, which copies its inode item and both extent items
  to the log tree.
- An xattr is set on the file, which sets the
  BTRFS_INODE_COPY_EVERYTHING flag.
- The range 4k-8k in the file is written using direct I/O. i_size is
  extended to 8k, but the ordered extent is still in flight.
- The file is fsync'd. Since BTRFS_INODE_COPY_EVERYTHING is set, this
  calls copy_inode_items_to_log(), which calls
  btrfs_log_prealloc_extents().
- btrfs_log_prealloc_extents() finds the 4k-12k prealloc extent in the
  filesystem tree. Since it starts before i_size, it skips it. Since it
  is the last item in its B-tree leaf, it calls btrfs_next_leaf().
- btrfs_next_leaf() unlocks the path.
- The ordered extent completion runs, which converts the 4k-8k part of
  the prealloc extent to written and inserts the remaining prealloc part
  from 8k-12k.
- btrfs_next_leaf() does a search and finds the new prealloc extent
  8k-12k.
- btrfs_log_prealloc_extents() copies the 8k-12k prealloc extent into
  the log tree. Note that it overlaps with the 4k-12k prealloc extent
  that was copied to the log tree by the first fsync.
- fsync calls btrfs_log_changed_extents(), which tries to log the 4k-8k
  extent that was written.
- This tries to drop the range 4k-8k in the log tree, which requires
  adjusting the start of the 4k-12k prealloc extent in the log tree to
  8k.
- btrfs_set_item_key_safe() sees that there is already an extent
  starting at 8k in the log tree and calls BUG().

Fix this by detecting when we're about to insert an overlapping file
extent item in the log tree and truncating the part that would overlap.

CC: stable@vger.kernel.org # 6.1+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
tiwai pushed a commit that referenced this pull request Jun 27, 2024
The frame pointer unwinder relies on a standard layout of the stack
frame, consisting of (in downward order)

   Calling frame:
     PC   <---------+
     LR             |
     SP             |
     FP             |
     .. locals ..   |
   Callee frame:    |
     PC             |
     LR             |
     SP             |
     FP   ----------+

where after storing its previous value on the stack, FP is made to point
at the location of PC in the callee stack frame, using the canonical
prologue:

   mov     ip, sp
   stmdb   sp!, {fp, ip, lr, pc}
   sub     fp, ip, #4

The ftrace code assumes that this activation record is pushed first, and
that any stack space for locals is allocated below this. Strict
adherence to this would imply that the caller's value of SP at the time
of the function call can always be obtained by adding 4 to FP (which
points to PC in the callee frame).

However, recent versions of GCC appear to deviate from this rule, and so
the only reliable way to obtain the caller's value of SP is to read it
from the activation record. Since this involves a read from memory
rather than simple arithmetic, we need to use the uaccess API here which
protects against inadvertent data aborts resulting from attempts to
dereference bogus FP values.

The plain uaccess API is ftrace instrumented itself, so to avoid
unbounded recursion, use the __get_kernel_nofault() primitive directly.

Closes: https://lore.kernel.org/all/alp44tukzo6mvcwl4ke4ehhmojrqnv6xfcdeuliybxfjfvgd3e@gpjvwj33cc76

Closes: https://lore.kernel.org/all/d870c149-4363-43de-b0ea-7125dec5608e@broadcom.com/

Reported-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reported-by: Justin Chen <justin.chen@broadcom.com>
Tested-by: Thorsten Scherer <t.scherer@eckelmann.de>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
tiwai pushed a commit that referenced this pull request Jun 27, 2024
Shin'ichiro reported that when he's running fstests' test-case
btrfs/167 on emulated zoned devices, he's seeing the following NULL
pointer dereference in 'btrfs_zone_finish_endio()':

  Oops: general protection fault, probably for non-canonical address 0xdffffc0000000011: 0000 [#1] PREEMPT SMP KASAN NOPTI
  KASAN: null-ptr-deref in range [0x0000000000000088-0x000000000000008f]
  CPU: 4 PID: 2332440 Comm: kworker/u80:15 Tainted: G        W          6.10.0-rc2-kts+ #4
  Hardware name: Supermicro Super Server/X11SPi-TF, BIOS 3.3 02/21/2020
  Workqueue: btrfs-endio-write btrfs_work_helper [btrfs]
  RIP: 0010:btrfs_zone_finish_endio.part.0+0x34/0x160 [btrfs]

  RSP: 0018:ffff88867f107a90 EFLAGS: 00010206
  RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff893e5534
  RDX: 0000000000000011 RSI: 0000000000000004 RDI: 0000000000000088
  RBP: 0000000000000002 R08: 0000000000000001 R09: ffffed1081696028
  R10: ffff88840b4b0143 R11: ffff88834dfff600 R12: ffff88840b4b0000
  R13: 0000000000020000 R14: 0000000000000000 R15: ffff888530ad5210
  FS:  0000000000000000(0000) GS:ffff888e3f800000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 00007f87223fff38 CR3: 00000007a7c6a002 CR4: 00000000007706f0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  PKRU: 55555554
  Call Trace:
   <TASK>
   ? __die_body.cold+0x19/0x27
   ? die_addr+0x46/0x70
   ? exc_general_protection+0x14f/0x250
   ? asm_exc_general_protection+0x26/0x30
   ? do_raw_read_unlock+0x44/0x70
   ? btrfs_zone_finish_endio.part.0+0x34/0x160 [btrfs]
   btrfs_finish_one_ordered+0x5d9/0x19a0 [btrfs]
   ? __pfx_lock_release+0x10/0x10
   ? do_raw_write_lock+0x90/0x260
   ? __pfx_do_raw_write_lock+0x10/0x10
   ? __pfx_btrfs_finish_one_ordered+0x10/0x10 [btrfs]
   ? _raw_write_unlock+0x23/0x40
   ? btrfs_finish_ordered_zoned+0x5a9/0x850 [btrfs]
   ? lock_acquire+0x435/0x500
   btrfs_work_helper+0x1b1/0xa70 [btrfs]
   ? __schedule+0x10a8/0x60b0
   ? __pfx___might_resched+0x10/0x10
   process_one_work+0x862/0x1410
   ? __pfx_lock_acquire+0x10/0x10
   ? __pfx_process_one_work+0x10/0x10
   ? assign_work+0x16c/0x240
   worker_thread+0x5e6/0x1010
   ? __pfx_worker_thread+0x10/0x10
   kthread+0x2c3/0x3a0
   ? trace_irq_enable.constprop.0+0xce/0x110
   ? __pfx_kthread+0x10/0x10
   ret_from_fork+0x31/0x70
   ? __pfx_kthread+0x10/0x10
   ret_from_fork_asm+0x1a/0x30
   </TASK>

Enabling CONFIG_BTRFS_ASSERT revealed the following assertion to
trigger:

  assertion failed: !list_empty(&ordered->list), in fs/btrfs/zoned.c:1815

This indicates, that we're missing the checksums list on the
ordered_extent. As btrfs/167 is doing a NOCOW write this is to be
expected.

Further analysis with drgn confirmed the assumption:

  >>> inode = prog.crashed_thread().stack_trace()[11]['ordered'].inode
  >>> btrfs_inode = drgn.container_of(inode, "struct btrfs_inode", \
         				"vfs_inode")
  >>> print(btrfs_inode.flags)
  (u32)1

As zoned emulation mode simulates conventional zones on regular devices,
we cannot use zone-append for writing. But we're only attaching dummy
checksums if we're doing a zone-append write.

So for NOCOW zoned data writes on conventional zones, also attach a
dummy checksum.

Reported-by: Shinichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Fixes: cbfce4c ("btrfs: optimize the logical to physical mapping for zoned writes")
CC: Naohiro Aota <Naohiro.Aota@wdc.com> # 6.6+
Tested-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Reviewed-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
tiwai pushed a commit that referenced this pull request Jun 27, 2024
The syzbot fuzzer found that the interrupt-URB completion callback in
the cdc-wdm driver was taking too long, and the driver's immediate
resubmission of interrupt URBs with -EPROTO status combined with the
dummy-hcd emulation to cause a CPU lockup:

cdc_wdm 1-1:1.0: nonzero urb status received: -71
cdc_wdm 1-1:1.0: wdm_int_callback - 0 bytes
watchdog: BUG: soft lockup - CPU#0 stuck for 26s! [syz-executor782:6625]
CPU#0 Utilization every 4s during lockup:
	#1:  98% system,	  0% softirq,	  3% hardirq,	  0% idle
	#2:  98% system,	  0% softirq,	  3% hardirq,	  0% idle
	#3:  98% system,	  0% softirq,	  3% hardirq,	  0% idle
	#4:  98% system,	  0% softirq,	  3% hardirq,	  0% idle
	#5:  98% system,	  1% softirq,	  3% hardirq,	  0% idle
Modules linked in:
irq event stamp: 73096
hardirqs last  enabled at (73095): [<ffff80008037bc00>] console_emit_next_record kernel/printk/printk.c:2935 [inline]
hardirqs last  enabled at (73095): [<ffff80008037bc00>] console_flush_all+0x650/0xb74 kernel/printk/printk.c:2994
hardirqs last disabled at (73096): [<ffff80008af10b00>] __el1_irq arch/arm64/kernel/entry-common.c:533 [inline]
hardirqs last disabled at (73096): [<ffff80008af10b00>] el1_interrupt+0x24/0x68 arch/arm64/kernel/entry-common.c:551
softirqs last  enabled at (73048): [<ffff8000801ea530>] softirq_handle_end kernel/softirq.c:400 [inline]
softirqs last  enabled at (73048): [<ffff8000801ea530>] handle_softirqs+0xa60/0xc34 kernel/softirq.c:582
softirqs last disabled at (73043): [<ffff800080020de8>] __do_softirq+0x14/0x20 kernel/softirq.c:588
CPU: 0 PID: 6625 Comm: syz-executor782 Tainted: G        W          6.10.0-rc2-syzkaller-g8867bbd4a056 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024

Testing showed that the problem did not occur if the two error
messages -- the first two lines above -- were removed; apparently adding
material to the kernel log takes a surprisingly large amount of time.

In any case, the best approach for preventing these lockups and to
avoid spamming the log with thousands of error messages per second is
to ratelimit the two dev_err() calls.  Therefore we replace them with
dev_err_ratelimited().

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Suggested-by: Greg KH <gregkh@linuxfoundation.org>
Reported-and-tested-by: syzbot+5f996b83575ef4058638@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/linux-usb/00000000000073d54b061a6a1c65@google.com/
Reported-and-tested-by: syzbot+1b2abad17596ad03dcff@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/linux-usb/000000000000f45085061aa9b37e@google.com/
Fixes: 9908a32 ("USB: remove err() macro from usb class drivers")
Link: https://lore.kernel.org/linux-usb/40dfa45b-5f21-4eef-a8c1-51a2f320e267@rowland.harvard.edu/
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/29855215-52f5-4385-b058-91f42c2bee18@rowland.harvard.edu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tiwai pushed a commit that referenced this pull request Jun 27, 2024
Luis has been reporting an assert failure when freeing an inode
cluster during inode inactivation for a while. The assert looks
like:

 XFS: Assertion failed: bp->b_flags & XBF_DONE, file: fs/xfs/xfs_trans_buf.c, line: 241
 ------------[ cut here ]------------
 kernel BUG at fs/xfs/xfs_message.c:102!
 Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN NOPTI
 CPU: 4 PID: 73 Comm: kworker/4:1 Not tainted 6.10.0-rc1 #4
 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
 Workqueue: xfs-inodegc/loop5 xfs_inodegc_worker [xfs]
 RIP: 0010:assfail (fs/xfs/xfs_message.c:102) xfs
 RSP: 0018:ffff88810188f7f0 EFLAGS: 00010202
 RAX: 0000000000000000 RBX: ffff88816e748250 RCX: 1ffffffff844b0e7
 RDX: 0000000000000004 RSI: ffff88810188f558 RDI: ffffffffc2431fa0
 RBP: 1ffff11020311f01 R08: 0000000042431f9f R09: ffffed1020311e9b
 R10: ffff88810188f4df R11: ffffffffac725d70 R12: ffff88817a3f4000
 R13: ffff88812182f000 R14: ffff88810188f998 R15: ffffffffc2423f80
 FS:  0000000000000000(0000) GS:ffff8881c8400000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 000055fe9d0f109c CR3: 000000014426c002 CR4: 0000000000770ef0
 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 DR3: 0000000000000000 DR6: 00000000fffe07f0 DR7: 0000000000000400
 PKRU: 55555554
 Call Trace:
  <TASK>
 xfs_trans_read_buf_map (fs/xfs/xfs_trans_buf.c:241 (discriminator 1)) xfs
 xfs_imap_to_bp (fs/xfs/xfs_trans.h:210 fs/xfs/libxfs/xfs_inode_buf.c:138) xfs
 xfs_inode_item_precommit (fs/xfs/xfs_inode_item.c:145) xfs
 xfs_trans_run_precommits (fs/xfs/xfs_trans.c:931) xfs
 __xfs_trans_commit (fs/xfs/xfs_trans.c:966) xfs
 xfs_inactive_ifree (fs/xfs/xfs_inode.c:1811) xfs
 xfs_inactive (fs/xfs/xfs_inode.c:2013) xfs
 xfs_inodegc_worker (fs/xfs/xfs_icache.c:1841 fs/xfs/xfs_icache.c:1886) xfs
 process_one_work (kernel/workqueue.c:3231)
 worker_thread (kernel/workqueue.c:3306 (discriminator 2) kernel/workqueue.c:3393 (discriminator 2))
 kthread (kernel/kthread.c:389)
 ret_from_fork (arch/x86/kernel/process.c:147)
 ret_from_fork_asm (arch/x86/entry/entry_64.S:257)
  </TASK>

And occurs when the the inode precommit handlers is attempt to look
up the inode cluster buffer to attach the inode for writeback.

The trail of logic that I can reconstruct is as follows.

	1. the inode is clean when inodegc runs, so it is not
	   attached to a cluster buffer when precommit runs.

	2. #1 implies the inode cluster buffer may be clean and not
	   pinned by dirty inodes when inodegc runs.

	3. #2 implies that the inode cluster buffer can be reclaimed
	   by memory pressure at any time.

	4. The assert failure implies that the cluster buffer was
	   attached to the transaction, but not marked done. It had
	   been accessed earlier in the transaction, but not marked
	   done.

	5. #4 implies the cluster buffer has been invalidated (i.e.
	   marked stale).

	6. #5 implies that the inode cluster buffer was instantiated
	   uninitialised in the transaction in xfs_ifree_cluster(),
	   which only instantiates the buffers to invalidate them
	   and never marks them as done.

Given factors 1-3, this issue is highly dependent on timing and
environmental factors. Hence the issue can be very difficult to
reproduce in some situations, but highly reliable in others. Luis
has an environment where it can be reproduced easily by g/531 but,
OTOH, I've reproduced it only once in ~2000 cycles of g/531.

I think the fix is to have xfs_ifree_cluster() set the XBF_DONE flag
on the cluster buffers, even though they may not be initialised. The
reasons why I think this is safe are:

	1. A buffer cache lookup hit on a XBF_STALE buffer will
	   clear the XBF_DONE flag. Hence all future users of the
	   buffer know they have to re-initialise the contents
	   before use and mark it done themselves.

	2. xfs_trans_binval() sets the XFS_BLI_STALE flag, which
	   means the buffer remains locked until the journal commit
	   completes and the buffer is unpinned. Hence once marked
	   XBF_STALE/XFS_BLI_STALE by xfs_ifree_cluster(), the only
	   context that can access the freed buffer is the currently
	   running transaction.

	3. #2 implies that future buffer lookups in the currently
	   running transaction will hit the transaction match code
	   and not the buffer cache. Hence XBF_STALE and
	   XFS_BLI_STALE will not be cleared unless the transaction
	   initialises and logs the buffer with valid contents
	   again. At which point, the buffer will be marked marked
	   XBF_DONE again, so having XBF_DONE already set on the
	   stale buffer is a moot point.

	4. #2 also implies that any concurrent access to that
	   cluster buffer will block waiting on the buffer lock
	   until the inode cluster has been fully freed and is no
	   longer an active inode cluster buffer.

	5. #4 + #1 means that any future user of the disk range of
	   that buffer will always see the range of disk blocks
	   covered by the cluster buffer as not done, and hence must
	   initialise the contents themselves.

	6. Setting XBF_DONE in xfs_ifree_cluster() then means the
	   unlinked inode precommit code will see a XBF_DONE buffer
	   from the transaction match as it expects. It can then
	   attach the stale but newly dirtied inode to the stale
	   but newly dirtied cluster buffer without unexpected
	   failures. The stale buffer will then sail through the
	   journal and do the right thing with the attached stale
	   inode during unpin.

Hence the fix is just one line of extra code. The explanation of
why we have to set XBF_DONE in xfs_ifree_cluster, OTOH, is long and
complex....

Fixes: 82842fe ("xfs: fix AGF vs inode cluster buffer deadlock")
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Tested-by: Luis Chamberlain <mcgrof@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
tiwai pushed a commit that referenced this pull request Jun 27, 2024
…git/netfilter/nf

Pablo Neira Ayuso says:

====================
Netfilter fixes for net

The following patchset contains Netfilter fixes for net:

Patch #1 fixes the suspicious RCU usage warning that resulted from the
	 recent fix for the race between namespace cleanup and gc in
	 ipset left out checking the pernet exit phase when calling
	 rcu_dereference_protected(), from Jozsef Kadlecsik.

Patch #2 fixes incorrect input and output netdevice in SRv6 prerouting
	 hooks, from Jianguo Wu.

Patch #3 moves nf_hooks_lwtunnel sysctl toggle to the netfilter core.
	 The connection tracking system is loaded on-demand, this
	 ensures availability of this knob regardless.

Patch #4-#5 adds selftests for SRv6 netfilter hooks also from Jianguo Wu.

netfilter pull request 24-06-19

* tag 'nf-24-06-19' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf:
  selftests: add selftest for the SRv6 End.DX6 behavior with netfilter
  selftests: add selftest for the SRv6 End.DX4 behavior with netfilter
  netfilter: move the sysctl nf_hooks_lwtunnel into the netfilter core
  seg6: fix parameter passing when calling NF_HOOK() in End.DX4 and End.DX6 behaviors
  netfilter: ipset: Fix suspicious rcu_dereference_protected()
====================

Link: https://lore.kernel.org/r/20240619170537.2846-1-pablo@netfilter.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
tiwai pushed a commit that referenced this pull request Jun 27, 2024
The code in ocfs2_dio_end_io_write() estimates number of necessary
transaction credits using ocfs2_calc_extend_credits().  This however does
not take into account that the IO could be arbitrarily large and can
contain arbitrary number of extents.

Extent tree manipulations do often extend the current transaction but not
in all of the cases.  For example if we have only single block extents in
the tree, ocfs2_mark_extent_written() will end up calling
ocfs2_replace_extent_rec() all the time and we will never extend the
current transaction and eventually exhaust all the transaction credits if
the IO contains many single block extents.  Once that happens a
WARN_ON(jbd2_handle_buffer_credits(handle) <= 0) is triggered in
jbd2_journal_dirty_metadata() and subsequently OCFS2 aborts in response to
this error.  This was actually triggered by one of our customers on a
heavily fragmented OCFS2 filesystem.

To fix the issue make sure the transaction always has enough credits for
one extent insert before each call of ocfs2_mark_extent_written().

Heming Zhao said:

------
PANIC: "Kernel panic - not syncing: OCFS2: (device dm-1): panic forced after error"

PID: xxx  TASK: xxxx  CPU: 5  COMMAND: "SubmitThread-CA"
  #0 machine_kexec at ffffffff8c069932
  #1 __crash_kexec at ffffffff8c1338fa
  #2 panic at ffffffff8c1d69b9
  #3 ocfs2_handle_error at ffffffffc0c86c0c [ocfs2]
  #4 __ocfs2_abort at ffffffffc0c88387 [ocfs2]
  #5 ocfs2_journal_dirty at ffffffffc0c51e98 [ocfs2]
  #6 ocfs2_split_extent at ffffffffc0c27ea3 [ocfs2]
  #7 ocfs2_change_extent_flag at ffffffffc0c28053 [ocfs2]
  torvalds#8 ocfs2_mark_extent_written at ffffffffc0c28347 [ocfs2]
  torvalds#9 ocfs2_dio_end_io_write at ffffffffc0c2bef9 [ocfs2]
torvalds#10 ocfs2_dio_end_io at ffffffffc0c2c0f5 [ocfs2]
torvalds#11 dio_complete at ffffffff8c2b9fa7
torvalds#12 do_blockdev_direct_IO at ffffffff8c2bc09f
torvalds#13 ocfs2_direct_IO at ffffffffc0c2b653 [ocfs2]
torvalds#14 generic_file_direct_write at ffffffff8c1dcf14
torvalds#15 __generic_file_write_iter at ffffffff8c1dd07b
torvalds#16 ocfs2_file_write_iter at ffffffffc0c49f1f [ocfs2]
torvalds#17 aio_write at ffffffff8c2cc72e
torvalds#18 kmem_cache_alloc at ffffffff8c248dde
torvalds#19 do_io_submit at ffffffff8c2ccada
torvalds#20 do_syscall_64 at ffffffff8c004984
torvalds#21 entry_SYSCALL_64_after_hwframe at ffffffff8c8000ba

Link: https://lkml.kernel.org/r/20240617095543.6971-1-jack@suse.cz
Link: https://lkml.kernel.org/r/20240614145243.8837-1-jack@suse.cz
Fixes: c15471f ("ocfs2: fix sparse file & data ordering issue in direct io")
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Reviewed-by: Heming Zhao <heming.zhao@suse.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
tiwai pushed a commit that referenced this pull request Jul 11, 2024
…play

During inode logging (and log replay too), we are holding a transaction
handle and we often need to call btrfs_iget(), which will read an inode
from its subvolume btree if it's not loaded in memory and that results in
allocating an inode with GFP_KERNEL semantics at the btrfs_alloc_inode()
callback - and this may recurse into the filesystem in case we are under
memory pressure and attempt to commit the current transaction, resulting
in a deadlock since the logging (or log replay) task is holding a
transaction handle open.

Syzbot reported this with the following stack traces:

  WARNING: possible circular locking dependency detected
  6.10.0-rc2-syzkaller-00361-g061d1af7b030 #0 Not tainted
  ------------------------------------------------------
  syz-executor.1/9919 is trying to acquire lock:
  ffffffff8dd3aac0 (fs_reclaim){+.+.}-{0:0}, at: might_alloc include/linux/sched/mm.h:334 [inline]
  ffffffff8dd3aac0 (fs_reclaim){+.+.}-{0:0}, at: slab_pre_alloc_hook mm/slub.c:3891 [inline]
  ffffffff8dd3aac0 (fs_reclaim){+.+.}-{0:0}, at: slab_alloc_node mm/slub.c:3981 [inline]
  ffffffff8dd3aac0 (fs_reclaim){+.+.}-{0:0}, at: kmem_cache_alloc_lru_noprof+0x58/0x2f0 mm/slub.c:4020

  but task is already holding lock:
  ffff88804b569358 (&ei->log_mutex){+.+.}-{3:3}, at: btrfs_log_inode+0x39c/0x4660 fs/btrfs/tree-log.c:6481

  which lock already depends on the new lock.

  the existing dependency chain (in reverse order) is:

  -> #3 (&ei->log_mutex){+.+.}-{3:3}:
         __mutex_lock_common kernel/locking/mutex.c:608 [inline]
         __mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752
         btrfs_log_inode+0x39c/0x4660 fs/btrfs/tree-log.c:6481
         btrfs_log_inode_parent+0x8cb/0x2a90 fs/btrfs/tree-log.c:7079
         btrfs_log_dentry_safe+0x59/0x80 fs/btrfs/tree-log.c:7180
         btrfs_sync_file+0x9c1/0xe10 fs/btrfs/file.c:1959
         vfs_fsync_range+0x141/0x230 fs/sync.c:188
         generic_write_sync include/linux/fs.h:2794 [inline]
         btrfs_do_write_iter+0x584/0x10c0 fs/btrfs/file.c:1705
         new_sync_write fs/read_write.c:497 [inline]
         vfs_write+0x6b6/0x1140 fs/read_write.c:590
         ksys_write+0x12f/0x260 fs/read_write.c:643
         do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
         __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386
         do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
         entry_SYSENTER_compat_after_hwframe+0x84/0x8e

  -> #2 (btrfs_trans_num_extwriters){++++}-{0:0}:
         join_transaction+0x164/0xf40 fs/btrfs/transaction.c:315
         start_transaction+0x427/0x1a70 fs/btrfs/transaction.c:700
         btrfs_commit_super+0xa1/0x110 fs/btrfs/disk-io.c:4170
         close_ctree+0xcb0/0xf90 fs/btrfs/disk-io.c:4324
         generic_shutdown_super+0x159/0x3d0 fs/super.c:642
         kill_anon_super+0x3a/0x60 fs/super.c:1226
         btrfs_kill_super+0x3b/0x50 fs/btrfs/super.c:2096
         deactivate_locked_super+0xbe/0x1a0 fs/super.c:473
         deactivate_super+0xde/0x100 fs/super.c:506
         cleanup_mnt+0x222/0x450 fs/namespace.c:1267
         task_work_run+0x14e/0x250 kernel/task_work.c:180
         resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
         exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
         exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
         __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
         syscall_exit_to_user_mode+0x278/0x2a0 kernel/entry/common.c:218
         __do_fast_syscall_32+0x80/0x120 arch/x86/entry/common.c:389
         do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
         entry_SYSENTER_compat_after_hwframe+0x84/0x8e

  -> #1 (btrfs_trans_num_writers){++++}-{0:0}:
         __lock_release kernel/locking/lockdep.c:5468 [inline]
         lock_release+0x33e/0x6c0 kernel/locking/lockdep.c:5774
         percpu_up_read include/linux/percpu-rwsem.h:99 [inline]
         __sb_end_write include/linux/fs.h:1650 [inline]
         sb_end_intwrite include/linux/fs.h:1767 [inline]
         __btrfs_end_transaction+0x5ca/0x920 fs/btrfs/transaction.c:1071
         btrfs_commit_inode_delayed_inode+0x228/0x330 fs/btrfs/delayed-inode.c:1301
         btrfs_evict_inode+0x960/0xe80 fs/btrfs/inode.c:5291
         evict+0x2ed/0x6c0 fs/inode.c:667
         iput_final fs/inode.c:1741 [inline]
         iput.part.0+0x5a8/0x7f0 fs/inode.c:1767
         iput+0x5c/0x80 fs/inode.c:1757
         dentry_unlink_inode+0x295/0x480 fs/dcache.c:400
         __dentry_kill+0x1d0/0x600 fs/dcache.c:603
         dput.part.0+0x4b1/0x9b0 fs/dcache.c:845
         dput+0x1f/0x30 fs/dcache.c:835
         ovl_stack_put+0x60/0x90 fs/overlayfs/util.c:132
         ovl_destroy_inode+0xc6/0x190 fs/overlayfs/super.c:182
         destroy_inode+0xc4/0x1b0 fs/inode.c:311
         iput_final fs/inode.c:1741 [inline]
         iput.part.0+0x5a8/0x7f0 fs/inode.c:1767
         iput+0x5c/0x80 fs/inode.c:1757
         dentry_unlink_inode+0x295/0x480 fs/dcache.c:400
         __dentry_kill+0x1d0/0x600 fs/dcache.c:603
         shrink_kill fs/dcache.c:1048 [inline]
         shrink_dentry_list+0x140/0x5d0 fs/dcache.c:1075
         prune_dcache_sb+0xeb/0x150 fs/dcache.c:1156
         super_cache_scan+0x32a/0x550 fs/super.c:221
         do_shrink_slab+0x44f/0x11c0 mm/shrinker.c:435
         shrink_slab_memcg mm/shrinker.c:548 [inline]
         shrink_slab+0xa87/0x1310 mm/shrinker.c:626
         shrink_one+0x493/0x7c0 mm/vmscan.c:4790
         shrink_many mm/vmscan.c:4851 [inline]
         lru_gen_shrink_node+0x89f/0x1750 mm/vmscan.c:4951
         shrink_node mm/vmscan.c:5910 [inline]
         kswapd_shrink_node mm/vmscan.c:6720 [inline]
         balance_pgdat+0x1105/0x1970 mm/vmscan.c:6911
         kswapd+0x5ea/0xbf0 mm/vmscan.c:7180
         kthread+0x2c1/0x3a0 kernel/kthread.c:389
         ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
         ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

  -> #0 (fs_reclaim){+.+.}-{0:0}:
         check_prev_add kernel/locking/lockdep.c:3134 [inline]
         check_prevs_add kernel/locking/lockdep.c:3253 [inline]
         validate_chain kernel/locking/lockdep.c:3869 [inline]
         __lock_acquire+0x2478/0x3b30 kernel/locking/lockdep.c:5137
         lock_acquire kernel/locking/lockdep.c:5754 [inline]
         lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719
         __fs_reclaim_acquire mm/page_alloc.c:3801 [inline]
         fs_reclaim_acquire+0x102/0x160 mm/page_alloc.c:3815
         might_alloc include/linux/sched/mm.h:334 [inline]
         slab_pre_alloc_hook mm/slub.c:3891 [inline]
         slab_alloc_node mm/slub.c:3981 [inline]
         kmem_cache_alloc_lru_noprof+0x58/0x2f0 mm/slub.c:4020
         btrfs_alloc_inode+0x118/0xb20 fs/btrfs/inode.c:8411
         alloc_inode+0x5d/0x230 fs/inode.c:261
         iget5_locked fs/inode.c:1235 [inline]
         iget5_locked+0x1c9/0x2c0 fs/inode.c:1228
         btrfs_iget_locked fs/btrfs/inode.c:5590 [inline]
         btrfs_iget_path fs/btrfs/inode.c:5607 [inline]
         btrfs_iget+0xfb/0x230 fs/btrfs/inode.c:5636
         add_conflicting_inode fs/btrfs/tree-log.c:5657 [inline]
         copy_inode_items_to_log+0x1039/0x1e30 fs/btrfs/tree-log.c:5928
         btrfs_log_inode+0xa48/0x4660 fs/btrfs/tree-log.c:6592
         log_new_delayed_dentries fs/btrfs/tree-log.c:6363 [inline]
         btrfs_log_inode+0x27dd/0x4660 fs/btrfs/tree-log.c:6718
         btrfs_log_all_parents fs/btrfs/tree-log.c:6833 [inline]
         btrfs_log_inode_parent+0x22ba/0x2a90 fs/btrfs/tree-log.c:7141
         btrfs_log_dentry_safe+0x59/0x80 fs/btrfs/tree-log.c:7180
         btrfs_sync_file+0x9c1/0xe10 fs/btrfs/file.c:1959
         vfs_fsync_range+0x141/0x230 fs/sync.c:188
         generic_write_sync include/linux/fs.h:2794 [inline]
         btrfs_do_write_iter+0x584/0x10c0 fs/btrfs/file.c:1705
         do_iter_readv_writev+0x504/0x780 fs/read_write.c:741
         vfs_writev+0x36f/0xde0 fs/read_write.c:971
         do_pwritev+0x1b2/0x260 fs/read_write.c:1072
         __do_compat_sys_pwritev2 fs/read_write.c:1218 [inline]
         __se_compat_sys_pwritev2 fs/read_write.c:1210 [inline]
         __ia32_compat_sys_pwritev2+0x121/0x1b0 fs/read_write.c:1210
         do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
         __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386
         do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
         entry_SYSENTER_compat_after_hwframe+0x84/0x8e

  other info that might help us debug this:

  Chain exists of:
    fs_reclaim --> btrfs_trans_num_extwriters --> &ei->log_mutex

   Possible unsafe locking scenario:

         CPU0                    CPU1
         ----                    ----
    lock(&ei->log_mutex);
                                 lock(btrfs_trans_num_extwriters);
                                 lock(&ei->log_mutex);
    lock(fs_reclaim);

   *** DEADLOCK ***

  7 locks held by syz-executor.1/9919:
   #0: ffff88802be20420 (sb_writers#23){.+.+}-{0:0}, at: do_pwritev+0x1b2/0x260 fs/read_write.c:1072
   #1: ffff888065c0f8f0 (&sb->s_type->i_mutex_key#33){++++}-{3:3}, at: inode_lock include/linux/fs.h:791 [inline]
   #1: ffff888065c0f8f0 (&sb->s_type->i_mutex_key#33){++++}-{3:3}, at: btrfs_inode_lock+0xc8/0x110 fs/btrfs/inode.c:385
   #2: ffff888065c0f778 (&ei->i_mmap_lock){++++}-{3:3}, at: btrfs_inode_lock+0xee/0x110 fs/btrfs/inode.c:388
   #3: ffff88802be20610 (sb_internal#4){.+.+}-{0:0}, at: btrfs_sync_file+0x95b/0xe10 fs/btrfs/file.c:1952
   #4: ffff8880546323f0 (btrfs_trans_num_writers){++++}-{0:0}, at: join_transaction+0x430/0xf40 fs/btrfs/transaction.c:290
   #5: ffff888054632418 (btrfs_trans_num_extwriters){++++}-{0:0}, at: join_transaction+0x430/0xf40 fs/btrfs/transaction.c:290
   #6: ffff88804b569358 (&ei->log_mutex){+.+.}-{3:3}, at: btrfs_log_inode+0x39c/0x4660 fs/btrfs/tree-log.c:6481

  stack backtrace:
  CPU: 2 PID: 9919 Comm: syz-executor.1 Not tainted 6.10.0-rc2-syzkaller-00361-g061d1af7b030 #0
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
  Call Trace:
   <TASK>
   __dump_stack lib/dump_stack.c:88 [inline]
   dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
   check_noncircular+0x31a/0x400 kernel/locking/lockdep.c:2187
   check_prev_add kernel/locking/lockdep.c:3134 [inline]
   check_prevs_add kernel/locking/lockdep.c:3253 [inline]
   validate_chain kernel/locking/lockdep.c:3869 [inline]
   __lock_acquire+0x2478/0x3b30 kernel/locking/lockdep.c:5137
   lock_acquire kernel/locking/lockdep.c:5754 [inline]
   lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719
   __fs_reclaim_acquire mm/page_alloc.c:3801 [inline]
   fs_reclaim_acquire+0x102/0x160 mm/page_alloc.c:3815
   might_alloc include/linux/sched/mm.h:334 [inline]
   slab_pre_alloc_hook mm/slub.c:3891 [inline]
   slab_alloc_node mm/slub.c:3981 [inline]
   kmem_cache_alloc_lru_noprof+0x58/0x2f0 mm/slub.c:4020
   btrfs_alloc_inode+0x118/0xb20 fs/btrfs/inode.c:8411
   alloc_inode+0x5d/0x230 fs/inode.c:261
   iget5_locked fs/inode.c:1235 [inline]
   iget5_locked+0x1c9/0x2c0 fs/inode.c:1228
   btrfs_iget_locked fs/btrfs/inode.c:5590 [inline]
   btrfs_iget_path fs/btrfs/inode.c:5607 [inline]
   btrfs_iget+0xfb/0x230 fs/btrfs/inode.c:5636
   add_conflicting_inode fs/btrfs/tree-log.c:5657 [inline]
   copy_inode_items_to_log+0x1039/0x1e30 fs/btrfs/tree-log.c:5928
   btrfs_log_inode+0xa48/0x4660 fs/btrfs/tree-log.c:6592
   log_new_delayed_dentries fs/btrfs/tree-log.c:6363 [inline]
   btrfs_log_inode+0x27dd/0x4660 fs/btrfs/tree-log.c:6718
   btrfs_log_all_parents fs/btrfs/tree-log.c:6833 [inline]
   btrfs_log_inode_parent+0x22ba/0x2a90 fs/btrfs/tree-log.c:7141
   btrfs_log_dentry_safe+0x59/0x80 fs/btrfs/tree-log.c:7180
   btrfs_sync_file+0x9c1/0xe10 fs/btrfs/file.c:1959
   vfs_fsync_range+0x141/0x230 fs/sync.c:188
   generic_write_sync include/linux/fs.h:2794 [inline]
   btrfs_do_write_iter+0x584/0x10c0 fs/btrfs/file.c:1705
   do_iter_readv_writev+0x504/0x780 fs/read_write.c:741
   vfs_writev+0x36f/0xde0 fs/read_write.c:971
   do_pwritev+0x1b2/0x260 fs/read_write.c:1072
   __do_compat_sys_pwritev2 fs/read_write.c:1218 [inline]
   __se_compat_sys_pwritev2 fs/read_write.c:1210 [inline]
   __ia32_compat_sys_pwritev2+0x121/0x1b0 fs/read_write.c:1210
   do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
   __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386
   do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
   entry_SYSENTER_compat_after_hwframe+0x84/0x8e
  RIP: 0023:0xf7334579
  Code: b8 01 10 06 03 (...)
  RSP: 002b:00000000f5f265ac EFLAGS: 00000292 ORIG_RAX: 000000000000017b
  RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00000000200002c0
  RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000000000000
  RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
  R10: 0000000000000000 R11: 0000000000000292 R12: 0000000000000000
  R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

Fix this by ensuring we are under a NOFS scope whenever we call
btrfs_iget() during inode logging and log replay.

Reported-by: syzbot+8576cfa84070dce4d59b@syzkaller.appspotmail.com
Link: https://lore.kernel.org/linux-btrfs/000000000000274a3a061abbd928@google.com/
Fixes: 712e36c ("btrfs: use GFP_KERNEL in btrfs_alloc_inode")
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
tiwai pushed a commit that referenced this pull request Jul 11, 2024
Bos can be put with multiple unrelated dma-resv locks held. But
imported bos attempt to grab the bo dma-resv during dma-buf detach
that typically happens during cleanup. That leads to lockde splats
similar to the below and a potential ABBA deadlock.

Fix this by always taking the delayed workqueue cleanup path for
imported bos.

Requesting stable fixes from when the Xe driver was introduced,
since its usage of drm_exec and wide vm dma_resvs appear to be
the first reliable trigger of this.

[22982.116427] ============================================
[22982.116428] WARNING: possible recursive locking detected
[22982.116429] 6.10.0-rc2+ torvalds#10 Tainted: G     U  W
[22982.116430] --------------------------------------------
[22982.116430] glxgears:sh0/5785 is trying to acquire lock:
[22982.116431] ffff8c2bafa539a8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: dma_buf_detach+0x3b/0xf0
[22982.116438]
               but task is already holding lock:
[22982.116438] ffff8c2d9aba6da8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: drm_exec_lock_obj+0x49/0x2b0 [drm_exec]
[22982.116442]
               other info that might help us debug this:
[22982.116442]  Possible unsafe locking scenario:

[22982.116443]        CPU0
[22982.116444]        ----
[22982.116444]   lock(reservation_ww_class_mutex);
[22982.116445]   lock(reservation_ww_class_mutex);
[22982.116447]
                *** DEADLOCK ***

[22982.116447]  May be due to missing lock nesting notation

[22982.116448] 5 locks held by glxgears:sh0/5785:
[22982.116449]  #0: ffff8c2d9aba58c8 (&xef->vm.lock){+.+.}-{3:3}, at: xe_file_close+0xde/0x1c0 [xe]
[22982.116507]  #1: ffff8c2e28cc8480 (&vm->lock){++++}-{3:3}, at: xe_vm_close_and_put+0x161/0x9b0 [xe]
[22982.116578]  #2: ffff8c2e31982970 (&val->lock){.+.+}-{3:3}, at: xe_validation_ctx_init+0x6d/0x70 [xe]
[22982.116647]  #3: ffffacdc469478a8 (reservation_ww_class_acquire){+.+.}-{0:0}, at: xe_vma_destroy_unlocked+0x7f/0xe0 [xe]
[22982.116716]  #4: ffff8c2d9aba6da8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: drm_exec_lock_obj+0x49/0x2b0 [drm_exec]
[22982.116719]
               stack backtrace:
[22982.116720] CPU: 8 PID: 5785 Comm: glxgears:sh0 Tainted: G     U  W          6.10.0-rc2+ torvalds#10
[22982.116721] Hardware name: ASUS System Product Name/PRIME B560M-A AC, BIOS 2001 02/01/2023
[22982.116723] Call Trace:
[22982.116724]  <TASK>
[22982.116725]  dump_stack_lvl+0x77/0xb0
[22982.116727]  __lock_acquire+0x1232/0x2160
[22982.116730]  lock_acquire+0xcb/0x2d0
[22982.116732]  ? dma_buf_detach+0x3b/0xf0
[22982.116734]  ? __lock_acquire+0x417/0x2160
[22982.116736]  __ww_mutex_lock.constprop.0+0xd0/0x13b0
[22982.116738]  ? dma_buf_detach+0x3b/0xf0
[22982.116741]  ? dma_buf_detach+0x3b/0xf0
[22982.116743]  ? ww_mutex_lock+0x2b/0x90
[22982.116745]  ww_mutex_lock+0x2b/0x90
[22982.116747]  dma_buf_detach+0x3b/0xf0
[22982.116749]  drm_prime_gem_destroy+0x2f/0x40 [drm]
[22982.116775]  xe_ttm_bo_destroy+0x32/0x220 [xe]
[22982.116818]  ? __mutex_unlock_slowpath+0x3a/0x290
[22982.116821]  drm_exec_unlock_all+0xa1/0xd0 [drm_exec]
[22982.116823]  drm_exec_fini+0x12/0xb0 [drm_exec]
[22982.116824]  xe_validation_ctx_fini+0x15/0x40 [xe]
[22982.116892]  xe_vma_destroy_unlocked+0xb1/0xe0 [xe]
[22982.116959]  xe_vm_close_and_put+0x41a/0x9b0 [xe]
[22982.117025]  ? xa_find+0xe3/0x1e0
[22982.117028]  xe_file_close+0x10a/0x1c0 [xe]
[22982.117074]  drm_file_free+0x22a/0x280 [drm]
[22982.117099]  drm_release_noglobal+0x22/0x70 [drm]
[22982.117119]  __fput+0xf1/0x2d0
[22982.117122]  task_work_run+0x59/0x90
[22982.117125]  do_exit+0x330/0xb40
[22982.117127]  do_group_exit+0x36/0xa0
[22982.117129]  get_signal+0xbd2/0xbe0
[22982.117131]  arch_do_signal_or_restart+0x3e/0x240
[22982.117134]  syscall_exit_to_user_mode+0x1e7/0x290
[22982.117137]  do_syscall_64+0xa1/0x180
[22982.117139]  ? lock_acquire+0xcb/0x2d0
[22982.117140]  ? __set_task_comm+0x28/0x1e0
[22982.117141]  ? find_held_lock+0x2b/0x80
[22982.117144]  ? __set_task_comm+0xe1/0x1e0
[22982.117145]  ? lock_release+0xca/0x290
[22982.117147]  ? __do_sys_prctl+0x245/0xab0
[22982.117149]  ? lockdep_hardirqs_on_prepare+0xde/0x190
[22982.117150]  ? syscall_exit_to_user_mode+0xb0/0x290
[22982.117152]  ? do_syscall_64+0xa1/0x180
[22982.117154]  ? __lock_acquire+0x417/0x2160
[22982.117155]  ? reacquire_held_locks+0xd1/0x1f0
[22982.117156]  ? do_user_addr_fault+0x30c/0x790
[22982.117158]  ? lock_acquire+0xcb/0x2d0
[22982.117160]  ? find_held_lock+0x2b/0x80
[22982.117162]  ? do_user_addr_fault+0x357/0x790
[22982.117163]  ? lock_release+0xca/0x290
[22982.117164]  ? do_user_addr_fault+0x361/0x790
[22982.117166]  ? trace_hardirqs_off+0x4b/0xc0
[22982.117168]  ? clear_bhb_loop+0x45/0xa0
[22982.117170]  ? clear_bhb_loop+0x45/0xa0
[22982.117172]  ? clear_bhb_loop+0x45/0xa0
[22982.117174]  entry_SYSCALL_64_after_hwframe+0x76/0x7e
[22982.117176] RIP: 0033:0x7f943d267169
[22982.117192] Code: Unable to access opcode bytes at 0x7f943d26713f.
[22982.117193] RSP: 002b:00007f9430bffc80 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
[22982.117195] RAX: fffffffffffffe00 RBX: 0000000000000000 RCX: 00007f943d267169
[22982.117196] RDX: 0000000000000000 RSI: 0000000000000189 RDI: 00005622f89579d0
[22982.117197] RBP: 00007f9430bffcb0 R08: 0000000000000000 R09: 00000000ffffffff
[22982.117198] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
[22982.117199] R13: 0000000000000000 R14: 0000000000000000 R15: 00005622f89579d0
[22982.117202]  </TASK>

Fixes: dd08ebf ("drm/xe: Introduce a new DRM driver for Intel GPUs")
Cc: Christian König <christian.koenig@amd.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: dri-devel@lists.freedesktop.org
Cc: intel-xe@lists.freedesktop.org
Cc: <stable@vger.kernel.org> # v6.8+
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240628153848.4989-1-thomas.hellstrom@linux.intel.com
tiwai pushed a commit that referenced this pull request Jul 29, 2024
When using cachefiles, lockdep may emit something similar to the circular
locking dependency notice below.  The problem appears to stem from the
following:

 (1) Cachefiles manipulates xattrs on the files in its cache when called
     from ->writepages().

 (2) The setxattr() and removexattr() system call handlers get the name
     (and value) from userspace after taking the sb_writers lock, putting
     accesses of the vma->vm_lock and mm->mmap_lock inside of that.

 (3) The afs filesystem uses a per-inode lock to prevent multiple
     revalidation RPCs and in writeback vs truncate to prevent parallel
     operations from deadlocking against the server on one side and local
     page locks on the other.

Fix this by moving the getting of the name and value in {get,remove}xattr()
outside of the sb_writers lock.  This also has the minor benefits that we
don't need to reget these in the event of a retry and we never try to take
the sb_writers lock in the event we can't pull the name and value into the
kernel.

Alternative approaches that might fix this include moving the dispatch of a
write to the cache off to a workqueue or trying to do without the
validation lock in afs.  Note that this might also affect other filesystems
that use netfslib and/or cachefiles.

 ======================================================
 WARNING: possible circular locking dependency detected
 6.10.0-build2+ torvalds#956 Not tainted
 ------------------------------------------------------
 fsstress/6050 is trying to acquire lock:
 ffff888138fd82f0 (mapping.invalidate_lock#3){++++}-{3:3}, at: filemap_fault+0x26e/0x8b0

 but task is already holding lock:
 ffff888113f26d18 (&vma->vm_lock->lock){++++}-{3:3}, at: lock_vma_under_rcu+0x165/0x250

 which lock already depends on the new lock.

 the existing dependency chain (in reverse order) is:

 -> #4 (&vma->vm_lock->lock){++++}-{3:3}:
        __lock_acquire+0xaf0/0xd80
        lock_acquire.part.0+0x103/0x280
        down_write+0x3b/0x50
        vma_start_write+0x6b/0xa0
        vma_link+0xcc/0x140
        insert_vm_struct+0xb7/0xf0
        alloc_bprm+0x2c1/0x390
        kernel_execve+0x65/0x1a0
        call_usermodehelper_exec_async+0x14d/0x190
        ret_from_fork+0x24/0x40
        ret_from_fork_asm+0x1a/0x30

 -> #3 (&mm->mmap_lock){++++}-{3:3}:
        __lock_acquire+0xaf0/0xd80
        lock_acquire.part.0+0x103/0x280
        __might_fault+0x7c/0xb0
        strncpy_from_user+0x25/0x160
        removexattr+0x7f/0x100
        __do_sys_fremovexattr+0x7e/0xb0
        do_syscall_64+0x9f/0x100
        entry_SYSCALL_64_after_hwframe+0x76/0x7e

 -> #2 (sb_writers#14){.+.+}-{0:0}:
        __lock_acquire+0xaf0/0xd80
        lock_acquire.part.0+0x103/0x280
        percpu_down_read+0x3c/0x90
        vfs_iocb_iter_write+0xe9/0x1d0
        __cachefiles_write+0x367/0x430
        cachefiles_issue_write+0x299/0x2f0
        netfs_advance_write+0x117/0x140
        netfs_write_folio.isra.0+0x5ca/0x6e0
        netfs_writepages+0x230/0x2f0
        afs_writepages+0x4d/0x70
        do_writepages+0x1e8/0x3e0
        filemap_fdatawrite_wbc+0x84/0xa0
        __filemap_fdatawrite_range+0xa8/0xf0
        file_write_and_wait_range+0x59/0x90
        afs_release+0x10f/0x270
        __fput+0x25f/0x3d0
        __do_sys_close+0x43/0x70
        do_syscall_64+0x9f/0x100
        entry_SYSCALL_64_after_hwframe+0x76/0x7e

 -> #1 (&vnode->validate_lock){++++}-{3:3}:
        __lock_acquire+0xaf0/0xd80
        lock_acquire.part.0+0x103/0x280
        down_read+0x95/0x200
        afs_writepages+0x37/0x70
        do_writepages+0x1e8/0x3e0
        filemap_fdatawrite_wbc+0x84/0xa0
        filemap_invalidate_inode+0x167/0x1e0
        netfs_unbuffered_write_iter+0x1bd/0x2d0
        vfs_write+0x22e/0x320
        ksys_write+0xbc/0x130
        do_syscall_64+0x9f/0x100
        entry_SYSCALL_64_after_hwframe+0x76/0x7e

 -> #0 (mapping.invalidate_lock#3){++++}-{3:3}:
        check_noncircular+0x119/0x160
        check_prev_add+0x195/0x430
        __lock_acquire+0xaf0/0xd80
        lock_acquire.part.0+0x103/0x280
        down_read+0x95/0x200
        filemap_fault+0x26e/0x8b0
        __do_fault+0x57/0xd0
        do_pte_missing+0x23b/0x320
        __handle_mm_fault+0x2d4/0x320
        handle_mm_fault+0x14f/0x260
        do_user_addr_fault+0x2a2/0x500
        exc_page_fault+0x71/0x90
        asm_exc_page_fault+0x22/0x30

 other info that might help us debug this:

 Chain exists of:
   mapping.invalidate_lock#3 --> &mm->mmap_lock --> &vma->vm_lock->lock

  Possible unsafe locking scenario:

        CPU0                    CPU1
        ----                    ----
   rlock(&vma->vm_lock->lock);
                                lock(&mm->mmap_lock);
                                lock(&vma->vm_lock->lock);
   rlock(mapping.invalidate_lock#3);

  *** DEADLOCK ***

 1 lock held by fsstress/6050:
  #0: ffff888113f26d18 (&vma->vm_lock->lock){++++}-{3:3}, at: lock_vma_under_rcu+0x165/0x250

 stack backtrace:
 CPU: 0 PID: 6050 Comm: fsstress Not tainted 6.10.0-build2+ torvalds#956
 Hardware name: ASUS All Series/H97-PLUS, BIOS 2306 10/09/2014
 Call Trace:
  <TASK>
  dump_stack_lvl+0x57/0x80
  check_noncircular+0x119/0x160
  ? queued_spin_lock_slowpath+0x4be/0x510
  ? __pfx_check_noncircular+0x10/0x10
  ? __pfx_queued_spin_lock_slowpath+0x10/0x10
  ? mark_lock+0x47/0x160
  ? init_chain_block+0x9c/0xc0
  ? add_chain_block+0x84/0xf0
  check_prev_add+0x195/0x430
  __lock_acquire+0xaf0/0xd80
  ? __pfx___lock_acquire+0x10/0x10
  ? __lock_release.isra.0+0x13b/0x230
  lock_acquire.part.0+0x103/0x280
  ? filemap_fault+0x26e/0x8b0
  ? __pfx_lock_acquire.part.0+0x10/0x10
  ? rcu_is_watching+0x34/0x60
  ? lock_acquire+0xd7/0x120
  down_read+0x95/0x200
  ? filemap_fault+0x26e/0x8b0
  ? __pfx_down_read+0x10/0x10
  ? __filemap_get_folio+0x25/0x1a0
  filemap_fault+0x26e/0x8b0
  ? __pfx_filemap_fault+0x10/0x10
  ? find_held_lock+0x7c/0x90
  ? __pfx___lock_release.isra.0+0x10/0x10
  ? __pte_offset_map+0x99/0x110
  __do_fault+0x57/0xd0
  do_pte_missing+0x23b/0x320
  __handle_mm_fault+0x2d4/0x320
  ? __pfx___handle_mm_fault+0x10/0x10
  handle_mm_fault+0x14f/0x260
  do_user_addr_fault+0x2a2/0x500
  exc_page_fault+0x71/0x90
  asm_exc_page_fault+0x22/0x30

Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/r/2136178.1721725194@warthog.procyon.org.uk
cc: Alexander Viro <viro@zeniv.linux.org.uk>
cc: Christian Brauner <brauner@kernel.org>
cc: Jan Kara <jack@suse.cz>
cc: Jeff Layton <jlayton@kernel.org>
cc: Gao Xiang <xiang@kernel.org>
cc: Matthew Wilcox <willy@infradead.org>
cc: netfs@lists.linux.dev
cc: linux-erofs@lists.ozlabs.org
cc: linux-fsdevel@vger.kernel.org
[brauner: fix minor issues]
Signed-off-by: Christian Brauner <brauner@kernel.org>
tiwai pushed a commit that referenced this pull request Aug 12, 2024
When l2tp tunnels use a socket provided by userspace, we can hit
lockdep splats like the below when data is transmitted through another
(unrelated) userspace socket which then gets routed over l2tp.

This issue was previously discussed here:
https://lore.kernel.org/netdev/87sfialu2n.fsf@cloudflare.com/

The solution is to have lockdep treat socket locks of l2tp tunnel
sockets separately than those of standard INET sockets. To do so, use
a different lockdep subclass where lock nesting is possible.

  ============================================
  WARNING: possible recursive locking detected
  6.10.0+ torvalds#34 Not tainted
  --------------------------------------------
  iperf3/771 is trying to acquire lock:
  ffff8881027601d8 (slock-AF_INET/1){+.-.}-{2:2}, at: l2tp_xmit_skb+0x243/0x9d0

  but task is already holding lock:
  ffff888102650d98 (slock-AF_INET/1){+.-.}-{2:2}, at: tcp_v4_rcv+0x1848/0x1e10

  other info that might help us debug this:
   Possible unsafe locking scenario:

         CPU0
         ----
    lock(slock-AF_INET/1);
    lock(slock-AF_INET/1);

   *** DEADLOCK ***

   May be due to missing lock nesting notation

  10 locks held by iperf3/771:
   #0: ffff888102650258 (sk_lock-AF_INET){+.+.}-{0:0}, at: tcp_sendmsg+0x1a/0x40
   #1: ffffffff822ac220 (rcu_read_lock){....}-{1:2}, at: __ip_queue_xmit+0x4b/0xbc0
   #2: ffffffff822ac220 (rcu_read_lock){....}-{1:2}, at: ip_finish_output2+0x17a/0x1130
   #3: ffffffff822ac220 (rcu_read_lock){....}-{1:2}, at: process_backlog+0x28b/0x9f0
   #4: ffffffff822ac220 (rcu_read_lock){....}-{1:2}, at: ip_local_deliver_finish+0xf9/0x260
   #5: ffff888102650d98 (slock-AF_INET/1){+.-.}-{2:2}, at: tcp_v4_rcv+0x1848/0x1e10
   #6: ffffffff822ac220 (rcu_read_lock){....}-{1:2}, at: __ip_queue_xmit+0x4b/0xbc0
   #7: ffffffff822ac220 (rcu_read_lock){....}-{1:2}, at: ip_finish_output2+0x17a/0x1130
   torvalds#8: ffffffff822ac1e0 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0xcc/0x1450
   torvalds#9: ffff888101f33258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock#2){+...}-{2:2}, at: __dev_queue_xmit+0x513/0x1450

  stack backtrace:
  CPU: 2 UID: 0 PID: 771 Comm: iperf3 Not tainted 6.10.0+ torvalds#34
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
  Call Trace:
   <IRQ>
   dump_stack_lvl+0x69/0xa0
   dump_stack+0xc/0x20
   __lock_acquire+0x135d/0x2600
   ? srso_alias_return_thunk+0x5/0xfbef5
   lock_acquire+0xc4/0x2a0
   ? l2tp_xmit_skb+0x243/0x9d0
   ? __skb_checksum+0xa3/0x540
   _raw_spin_lock_nested+0x35/0x50
   ? l2tp_xmit_skb+0x243/0x9d0
   l2tp_xmit_skb+0x243/0x9d0
   l2tp_eth_dev_xmit+0x3c/0xc0
   dev_hard_start_xmit+0x11e/0x420
   sch_direct_xmit+0xc3/0x640
   __dev_queue_xmit+0x61c/0x1450
   ? ip_finish_output2+0xf4c/0x1130
   ip_finish_output2+0x6b6/0x1130
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __ip_finish_output+0x217/0x380
   ? srso_alias_return_thunk+0x5/0xfbef5
   __ip_finish_output+0x217/0x380
   ip_output+0x99/0x120
   __ip_queue_xmit+0xae4/0xbc0
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? tcp_options_write.constprop.0+0xcb/0x3e0
   ip_queue_xmit+0x34/0x40
   __tcp_transmit_skb+0x1625/0x1890
   __tcp_send_ack+0x1b8/0x340
   tcp_send_ack+0x23/0x30
   __tcp_ack_snd_check+0xa8/0x530
   ? srso_alias_return_thunk+0x5/0xfbef5
   tcp_rcv_established+0x412/0xd70
   tcp_v4_do_rcv+0x299/0x420
   tcp_v4_rcv+0x1991/0x1e10
   ip_protocol_deliver_rcu+0x50/0x220
   ip_local_deliver_finish+0x158/0x260
   ip_local_deliver+0xc8/0xe0
   ip_rcv+0xe5/0x1d0
   ? __pfx_ip_rcv+0x10/0x10
   __netif_receive_skb_one_core+0xce/0xe0
   ? process_backlog+0x28b/0x9f0
   __netif_receive_skb+0x34/0xd0
   ? process_backlog+0x28b/0x9f0
   process_backlog+0x2cb/0x9f0
   __napi_poll.constprop.0+0x61/0x280
   net_rx_action+0x332/0x670
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? find_held_lock+0x2b/0x80
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? srso_alias_return_thunk+0x5/0xfbef5
   handle_softirqs+0xda/0x480
   ? __dev_queue_xmit+0xa2c/0x1450
   do_softirq+0xa1/0xd0
   </IRQ>
   <TASK>
   __local_bh_enable_ip+0xc8/0xe0
   ? __dev_queue_xmit+0xa2c/0x1450
   __dev_queue_xmit+0xa48/0x1450
   ? ip_finish_output2+0xf4c/0x1130
   ip_finish_output2+0x6b6/0x1130
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __ip_finish_output+0x217/0x380
   ? srso_alias_return_thunk+0x5/0xfbef5
   __ip_finish_output+0x217/0x380
   ip_output+0x99/0x120
   __ip_queue_xmit+0xae4/0xbc0
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? tcp_options_write.constprop.0+0xcb/0x3e0
   ip_queue_xmit+0x34/0x40
   __tcp_transmit_skb+0x1625/0x1890
   tcp_write_xmit+0x766/0x2fb0
   ? __entry_text_end+0x102ba9/0x102bad
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __might_fault+0x74/0xc0
   ? srso_alias_return_thunk+0x5/0xfbef5
   __tcp_push_pending_frames+0x56/0x190
   tcp_push+0x117/0x310
   tcp_sendmsg_locked+0x14c1/0x1740
   tcp_sendmsg+0x28/0x40
   inet_sendmsg+0x5d/0x90
   sock_write_iter+0x242/0x2b0
   vfs_write+0x68d/0x800
   ? __pfx_sock_write_iter+0x10/0x10
   ksys_write+0xc8/0xf0
   __x64_sys_write+0x3d/0x50
   x64_sys_call+0xfaf/0x1f50
   do_syscall_64+0x6d/0x140
   entry_SYSCALL_64_after_hwframe+0x76/0x7e
  RIP: 0033:0x7f4d143af992
  Code: c3 8b 07 85 c0 75 24 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 <c3> e9 01 cc ff ff 41 54 b8 02 00 00 0
  RSP: 002b:00007ffd65032058 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
  RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f4d143af992
  RDX: 0000000000000025 RSI: 00007f4d143f3bcc RDI: 0000000000000005
  RBP: 00007f4d143f2b28 R08: 0000000000000000 R09: 0000000000000000
  R10: 0000000000000000 R11: 0000000000000246 R12: 00007f4d143f3bcc
  R13: 0000000000000005 R14: 0000000000000000 R15: 00007ffd650323f0
   </TASK>

Fixes: 0b2c597 ("l2tp: close all race conditions in l2tp_tunnel_register()")
Suggested-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot+6acef9e0a4d1f46c83d4@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=6acef9e0a4d1f46c83d4
CC: gnault@redhat.com
CC: cong.wang@bytedance.com
Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: Tom Parkin <tparkin@katalix.com>
Link: https://patch.msgid.link/20240806160626.1248317-1-jchapman@katalix.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
tiwai pushed a commit that referenced this pull request Aug 19, 2024
Lockdep reported a warning in Linux version 6.6:

[  414.344659] ================================
[  414.345155] WARNING: inconsistent lock state
[  414.345658] 6.6.0-07439-gba2303cacfda #6 Not tainted
[  414.346221] --------------------------------
[  414.346712] inconsistent {IN-SOFTIRQ-W} -> {SOFTIRQ-ON-W} usage.
[  414.347545] kworker/u10:3/1152 [HC0[0]:SC0[0]:HE0:SE1] takes:
[  414.349245] ffff88810edd1098 (&sbq->ws[i].wait){+.?.}-{2:2}, at: blk_mq_dispatch_rq_list+0x131c/0x1ee0
[  414.351204] {IN-SOFTIRQ-W} state was registered at:
[  414.351751]   lock_acquire+0x18d/0x460
[  414.352218]   _raw_spin_lock_irqsave+0x39/0x60
[  414.352769]   __wake_up_common_lock+0x22/0x60
[  414.353289]   sbitmap_queue_wake_up+0x375/0x4f0
[  414.353829]   sbitmap_queue_clear+0xdd/0x270
[  414.354338]   blk_mq_put_tag+0xdf/0x170
[  414.354807]   __blk_mq_free_request+0x381/0x4d0
[  414.355335]   blk_mq_free_request+0x28b/0x3e0
[  414.355847]   __blk_mq_end_request+0x242/0xc30
[  414.356367]   scsi_end_request+0x2c1/0x830
[  414.345155] WARNING: inconsistent lock state
[  414.345658] 6.6.0-07439-gba2303cacfda #6 Not tainted
[  414.346221] --------------------------------
[  414.346712] inconsistent {IN-SOFTIRQ-W} -> {SOFTIRQ-ON-W} usage.
[  414.347545] kworker/u10:3/1152 [HC0[0]:SC0[0]:HE0:SE1] takes:
[  414.349245] ffff88810edd1098 (&sbq->ws[i].wait){+.?.}-{2:2}, at: blk_mq_dispatch_rq_list+0x131c/0x1ee0
[  414.351204] {IN-SOFTIRQ-W} state was registered at:
[  414.351751]   lock_acquire+0x18d/0x460
[  414.352218]   _raw_spin_lock_irqsave+0x39/0x60
[  414.352769]   __wake_up_common_lock+0x22/0x60
[  414.353289]   sbitmap_queue_wake_up+0x375/0x4f0
[  414.353829]   sbitmap_queue_clear+0xdd/0x270
[  414.354338]   blk_mq_put_tag+0xdf/0x170
[  414.354807]   __blk_mq_free_request+0x381/0x4d0
[  414.355335]   blk_mq_free_request+0x28b/0x3e0
[  414.355847]   __blk_mq_end_request+0x242/0xc30
[  414.356367]   scsi_end_request+0x2c1/0x830
[  414.356863]   scsi_io_completion+0x177/0x1610
[  414.357379]   scsi_complete+0x12f/0x260
[  414.357856]   blk_complete_reqs+0xba/0xf0
[  414.358338]   __do_softirq+0x1b0/0x7a2
[  414.358796]   irq_exit_rcu+0x14b/0x1a0
[  414.359262]   sysvec_call_function_single+0xaf/0xc0
[  414.359828]   asm_sysvec_call_function_single+0x1a/0x20
[  414.360426]   default_idle+0x1e/0x30
[  414.360873]   default_idle_call+0x9b/0x1f0
[  414.361390]   do_idle+0x2d2/0x3e0
[  414.361819]   cpu_startup_entry+0x55/0x60
[  414.362314]   start_secondary+0x235/0x2b0
[  414.362809]   secondary_startup_64_no_verify+0x18f/0x19b
[  414.363413] irq event stamp: 428794
[  414.363825] hardirqs last  enabled at (428793): [<ffffffff816bfd1c>] ktime_get+0x1dc/0x200
[  414.364694] hardirqs last disabled at (428794): [<ffffffff85470177>] _raw_spin_lock_irq+0x47/0x50
[  414.365629] softirqs last  enabled at (428444): [<ffffffff85474780>] __do_softirq+0x540/0x7a2
[  414.366522] softirqs last disabled at (428419): [<ffffffff813f65ab>] irq_exit_rcu+0x14b/0x1a0
[  414.367425]
               other info that might help us debug this:
[  414.368194]  Possible unsafe locking scenario:
[  414.368900]        CPU0
[  414.369225]        ----
[  414.369548]   lock(&sbq->ws[i].wait);
[  414.370000]   <Interrupt>
[  414.370342]     lock(&sbq->ws[i].wait);
[  414.370802]
                *** DEADLOCK ***
[  414.371569] 5 locks held by kworker/u10:3/1152:
[  414.372088]  #0: ffff88810130e938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x357/0x13f0
[  414.373180]  #1: ffff88810201fdb8 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x3a3/0x13f0
[  414.374384]  #2: ffffffff86ffbdc0 (rcu_read_lock){....}-{1:2}, at: blk_mq_run_hw_queue+0x637/0xa00
[  414.375342]  #3: ffff88810edd1098 (&sbq->ws[i].wait){+.?.}-{2:2}, at: blk_mq_dispatch_rq_list+0x131c/0x1ee0
[  414.376377]  #4: ffff888106205a08 (&hctx->dispatch_wait_lock){+.-.}-{2:2}, at: blk_mq_dispatch_rq_list+0x1337/0x1ee0
[  414.378607]
               stack backtrace:
[  414.379177] CPU: 0 PID: 1152 Comm: kworker/u10:3 Not tainted 6.6.0-07439-gba2303cacfda #6
[  414.380032] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
[  414.381177] Workqueue: writeback wb_workfn (flush-253:0)
[  414.381805] Call Trace:
[  414.382136]  <TASK>
[  414.382429]  dump_stack_lvl+0x91/0xf0
[  414.382884]  mark_lock_irq+0xb3b/0x1260
[  414.383367]  ? __pfx_mark_lock_irq+0x10/0x10
[  414.383889]  ? stack_trace_save+0x8e/0xc0
[  414.384373]  ? __pfx_stack_trace_save+0x10/0x10
[  414.384903]  ? graph_lock+0xcf/0x410
[  414.385350]  ? save_trace+0x3d/0xc70
[  414.385808]  mark_lock.part.20+0x56d/0xa90
[  414.386317]  mark_held_locks+0xb0/0x110
[  414.386791]  ? __pfx_do_raw_spin_lock+0x10/0x10
[  414.387320]  lockdep_hardirqs_on_prepare+0x297/0x3f0
[  414.387901]  ? _raw_spin_unlock_irq+0x28/0x50
[  414.388422]  trace_hardirqs_on+0x58/0x100
[  414.388917]  _raw_spin_unlock_irq+0x28/0x50
[  414.389422]  __blk_mq_tag_busy+0x1d6/0x2a0
[  414.389920]  __blk_mq_get_driver_tag+0x761/0x9f0
[  414.390899]  blk_mq_dispatch_rq_list+0x1780/0x1ee0
[  414.391473]  ? __pfx_blk_mq_dispatch_rq_list+0x10/0x10
[  414.392070]  ? sbitmap_get+0x2b8/0x450
[  414.392533]  ? __blk_mq_get_driver_tag+0x210/0x9f0
[  414.393095]  __blk_mq_sched_dispatch_requests+0xd99/0x1690
[  414.393730]  ? elv_attempt_insert_merge+0x1b1/0x420
[  414.394302]  ? __pfx___blk_mq_sched_dispatch_requests+0x10/0x10
[  414.394970]  ? lock_acquire+0x18d/0x460
[  414.395456]  ? blk_mq_run_hw_queue+0x637/0xa00
[  414.395986]  ? __pfx_lock_acquire+0x10/0x10
[  414.396499]  blk_mq_sched_dispatch_requests+0x109/0x190
[  414.397100]  blk_mq_run_hw_queue+0x66e/0xa00
[  414.397616]  blk_mq_flush_plug_list.part.17+0x614/0x2030
[  414.398244]  ? __pfx_blk_mq_flush_plug_list.part.17+0x10/0x10
[  414.398897]  ? writeback_sb_inodes+0x241/0xcc0
[  414.399429]  blk_mq_flush_plug_list+0x65/0x80
[  414.399957]  __blk_flush_plug+0x2f1/0x530
[  414.400458]  ? __pfx___blk_flush_plug+0x10/0x10
[  414.400999]  blk_finish_plug+0x59/0xa0
[  414.401467]  wb_writeback+0x7cc/0x920
[  414.401935]  ? __pfx_wb_writeback+0x10/0x10
[  414.402442]  ? mark_held_locks+0xb0/0x110
[  414.402931]  ? __pfx_do_raw_spin_lock+0x10/0x10
[  414.403462]  ? lockdep_hardirqs_on_prepare+0x297/0x3f0
[  414.404062]  wb_workfn+0x2b3/0xcf0
[  414.404500]  ? __pfx_wb_workfn+0x10/0x10
[  414.404989]  process_scheduled_works+0x432/0x13f0
[  414.405546]  ? __pfx_process_scheduled_works+0x10/0x10
[  414.406139]  ? do_raw_spin_lock+0x101/0x2a0
[  414.406641]  ? assign_work+0x19b/0x240
[  414.407106]  ? lock_is_held_type+0x9d/0x110
[  414.407604]  worker_thread+0x6f2/0x1160
[  414.408075]  ? __kthread_parkme+0x62/0x210
[  414.408572]  ? lockdep_hardirqs_on_prepare+0x297/0x3f0
[  414.409168]  ? __kthread_parkme+0x13c/0x210
[  414.409678]  ? __pfx_worker_thread+0x10/0x10
[  414.410191]  kthread+0x33c/0x440
[  414.410602]  ? __pfx_kthread+0x10/0x10
[  414.411068]  ret_from_fork+0x4d/0x80
[  414.411526]  ? __pfx_kthread+0x10/0x10
[  414.411993]  ret_from_fork_asm+0x1b/0x30
[  414.412489]  </TASK>

When interrupt is turned on while a lock holding by spin_lock_irq it
throws a warning because of potential deadlock.

blk_mq_prep_dispatch_rq
 blk_mq_get_driver_tag
  __blk_mq_get_driver_tag
   __blk_mq_alloc_driver_tag
    blk_mq_tag_busy -> tag is already busy
    // failed to get driver tag
 blk_mq_mark_tag_wait
  spin_lock_irq(&wq->lock) -> lock A (&sbq->ws[i].wait)
  __add_wait_queue(wq, wait) -> wait queue active
  blk_mq_get_driver_tag
  __blk_mq_tag_busy
-> 1) tag must be idle, which means there can't be inflight IO
   spin_lock_irq(&tags->lock) -> lock B (hctx->tags)
   spin_unlock_irq(&tags->lock) -> unlock B, turn on interrupt accidentally
-> 2) context must be preempt by IO interrupt to trigger deadlock.

As shown above, the deadlock is not possible in theory, but the warning
still need to be fixed.

Fix it by using spin_lock_irqsave to get lockB instead of spin_lock_irq.

Fixes: 4f1731d ("blk-mq: fix potential io hang by wrong 'wake_batch'")
Signed-off-by: Li Lingfeng <lilingfeng3@huawei.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20240815024736.2040971-1-lilingfeng@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
tiwai pushed a commit that referenced this pull request Sep 4, 2024
UBSAN reports the following 'subtraction overflow' error when booting
in a virtual machine on Android:

 | Internal error: UBSAN: integer subtraction overflow: 00000000f2005515 [#1] PREEMPT SMP
 | Modules linked in:
 | CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.10.0-00006-g3cbe9e5abd46-dirty #4
 | Hardware name: linux,dummy-virt (DT)
 | pstate: 600000c5 (nZCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
 | pc : cancel_delayed_work+0x34/0x44
 | lr : cancel_delayed_work+0x2c/0x44
 | sp : ffff80008002ba60
 | x29: ffff80008002ba60 x28: 0000000000000000 x27: 0000000000000000
 | x26: 0000000000000000 x25: 0000000000000000 x24: 0000000000000000
 | x23: 0000000000000000 x22: 0000000000000000 x21: ffff1f65014cd3c0
 | x20: ffffc0e84c9d0da0 x19: ffffc0e84cab3558 x18: ffff800080009058
 | x17: 00000000247ee1f8 x16: 00000000247ee1f8 x15: 00000000bdcb279d
 | x14: 0000000000000001 x13: 0000000000000075 x12: 00000a0000000000
 | x11: ffff1f6501499018 x10: 00984901651fffff x9 : ffff5e7cc35af000
 | x8 : 0000000000000001 x7 : 3d4d455453595342 x6 : 000000004e514553
 | x5 : ffff1f6501499265 x4 : ffff1f650ff60b10 x3 : 0000000000000620
 | x2 : ffff80008002ba78 x1 : 0000000000000000 x0 : 0000000000000000
 | Call trace:
 |  cancel_delayed_work+0x34/0x44
 |  deferred_probe_extend_timeout+0x20/0x70
 |  driver_register+0xa8/0x110
 |  __platform_driver_register+0x28/0x3c
 |  syscon_init+0x24/0x38
 |  do_one_initcall+0xe4/0x338
 |  do_initcall_level+0xac/0x178
 |  do_initcalls+0x5c/0xa0
 |  do_basic_setup+0x20/0x30
 |  kernel_init_freeable+0x8c/0xf8
 |  kernel_init+0x28/0x1b4
 |  ret_from_fork+0x10/0x20
 | Code: f9000fbf 97fffa2f 39400268 37100048 (d42aa2a0)
 | ---[ end trace 0000000000000000 ]---
 | Kernel panic - not syncing: UBSAN: integer subtraction overflow: Fatal exception

This is due to shift_and_mask() using a signed immediate to construct
the mask and being called with a shift of 31 (WORK_OFFQ_POOL_SHIFT) so
that it ends up decrementing from INT_MIN.

Use an unsigned constant '1U' to generate the mask in shift_and_mask().

Cc: Tejun Heo <tj@kernel.org>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Fixes: 1211f3b ("workqueue: Preserve OFFQ bits in cancel[_sync] paths")
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
tiwai pushed a commit that referenced this pull request Oct 25, 2024
On the node of an NFS client, some files saved in the mountpoint of the
NFS server were copied to another location of the same NFS server.
Accidentally, the nfs42_complete_copies() got a NULL-pointer dereference
crash with the following syslog:

[232064.838881] NFSv4: state recovery failed for open file nfs/pvc-12b5200d-cd0f-46a3-b9f0-af8f4fe0ef64.qcow2, error = -116
[232064.839360] NFSv4: state recovery failed for open file nfs/pvc-12b5200d-cd0f-46a3-b9f0-af8f4fe0ef64.qcow2, error = -116
[232066.588183] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000058
[232066.588586] Mem abort info:
[232066.588701]   ESR = 0x0000000096000007
[232066.588862]   EC = 0x25: DABT (current EL), IL = 32 bits
[232066.589084]   SET = 0, FnV = 0
[232066.589216]   EA = 0, S1PTW = 0
[232066.589340]   FSC = 0x07: level 3 translation fault
[232066.589559] Data abort info:
[232066.589683]   ISV = 0, ISS = 0x00000007
[232066.589842]   CM = 0, WnR = 0
[232066.589967] user pgtable: 64k pages, 48-bit VAs, pgdp=00002000956ff400
[232066.590231] [0000000000000058] pgd=08001100ae100003, p4d=08001100ae100003, pud=08001100ae100003, pmd=08001100b3c00003, pte=0000000000000000
[232066.590757] Internal error: Oops: 96000007 [#1] SMP
[232066.590958] Modules linked in: rpcsec_gss_krb5 auth_rpcgss nfsv4 dns_resolver nfs lockd grace fscache netfs ocfs2_dlmfs ocfs2_stack_o2cb ocfs2_dlm vhost_net vhost vhost_iotlb tap tun ipt_rpfilter xt_multiport ip_set_hash_ip ip_set_hash_net xfrm_interface xfrm6_tunnel tunnel4 tunnel6 esp4 ah4 wireguard libcurve25519_generic veth xt_addrtype xt_set nf_conntrack_netlink ip_set_hash_ipportnet ip_set_hash_ipportip ip_set_bitmap_port ip_set_hash_ipport dummy ip_set ip_vs_sh ip_vs_wrr ip_vs_rr ip_vs iptable_filter sch_ingress nfnetlink_cttimeout vport_gre ip_gre ip_tunnel gre vport_geneve geneve vport_vxlan vxlan ip6_udp_tunnel udp_tunnel openvswitch nf_conncount dm_round_robin dm_service_time dm_multipath xt_nat xt_MASQUERADE nft_chain_nat nf_nat xt_mark xt_conntrack xt_comment nft_compat nft_counter nf_tables nfnetlink ocfs2 ocfs2_nodemanager ocfs2_stackglue iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi ipmi_ssif nbd overlay 8021q garp mrp bonding tls rfkill sunrpc ext4 mbcache jbd2
[232066.591052]  vfat fat cas_cache cas_disk ses enclosure scsi_transport_sas sg acpi_ipmi ipmi_si ipmi_devintf ipmi_msghandler ip_tables vfio_pci vfio_pci_core vfio_virqfd vfio_iommu_type1 vfio dm_mirror dm_region_hash dm_log dm_mod nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 br_netfilter bridge stp llc fuse xfs libcrc32c ast drm_vram_helper qla2xxx drm_kms_helper syscopyarea crct10dif_ce sysfillrect ghash_ce sysimgblt sha2_ce fb_sys_fops cec sha256_arm64 sha1_ce drm_ttm_helper ttm nvme_fc igb sbsa_gwdt nvme_fabrics drm nvme_core i2c_algo_bit i40e scsi_transport_fc megaraid_sas aes_neon_bs
[232066.596953] CPU: 6 PID: 4124696 Comm: 10.253.166.125- Kdump: loaded Not tainted 5.15.131-9.cl9_ocfs2.aarch64 #1
[232066.597356] Hardware name: Great Wall .\x93\x8e...RF6260 V5/GWMSSE2GL1T, BIOS T656FBE_V3.0.18 2024-01-06
[232066.597721] pstate: 20400009 (nzCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[232066.598034] pc : nfs4_reclaim_open_state+0x220/0x800 [nfsv4]
[232066.598327] lr : nfs4_reclaim_open_state+0x12c/0x800 [nfsv4]
[232066.598595] sp : ffff8000f568fc70
[232066.598731] x29: ffff8000f568fc70 x28: 0000000000001000 x27: ffff21003db33000
[232066.599030] x26: ffff800005521ae0 x25: ffff0100f98fa3f0 x24: 0000000000000001
[232066.599319] x23: ffff800009920008 x22: ffff21003db33040 x21: ffff21003db33050
[232066.599628] x20: ffff410172fe9e40 x19: ffff410172fe9e00 x18: 0000000000000000
[232066.599914] x17: 0000000000000000 x16: 0000000000000004 x15: 0000000000000000
[232066.600195] x14: 0000000000000000 x13: ffff800008e685a8 x12: 00000000eac0c6e6
[232066.600498] x11: 0000000000000000 x10: 0000000000000008 x9 : ffff8000054e5828
[232066.600784] x8 : 00000000ffffffbf x7 : 0000000000000001 x6 : 000000000a9eb14a
[232066.601062] x5 : 0000000000000000 x4 : ffff70ff8a14a800 x3 : 0000000000000058
[232066.601348] x2 : 0000000000000001 x1 : 54dce46366daa6c6 x0 : 0000000000000000
[232066.601636] Call trace:
[232066.601749]  nfs4_reclaim_open_state+0x220/0x800 [nfsv4]
[232066.601998]  nfs4_do_reclaim+0x1b8/0x28c [nfsv4]
[232066.602218]  nfs4_state_manager+0x928/0x10f0 [nfsv4]
[232066.602455]  nfs4_run_state_manager+0x78/0x1b0 [nfsv4]
[232066.602690]  kthread+0x110/0x114
[232066.602830]  ret_from_fork+0x10/0x20
[232066.602985] Code: 1400000d f9403f20 f9402e61 91016003 (f9402c00)
[232066.603284] SMP: stopping secondary CPUs
[232066.606936] Starting crashdump kernel...
[232066.607146] Bye!

Analysing the vmcore, we know that nfs4_copy_state listed by destination
nfs_server->ss_copies was added by the field copies in handle_async_copy(),
and we found a waiting copy process with the stack as:
PID: 3511963  TASK: ffff710028b47e00  CPU: 0   COMMAND: "cp"
 #0 [ffff8001116ef740] __switch_to at ffff8000081b92f4
 #1 [ffff8001116ef760] __schedule at ffff800008dd0650
 #2 [ffff8001116ef7c0] schedule at ffff800008dd0a00
 #3 [ffff8001116ef7e0] schedule_timeout at ffff800008dd6aa0
 #4 [ffff8001116ef860] __wait_for_common at ffff800008dd166c
 #5 [ffff8001116ef8e0] wait_for_completion_interruptible at ffff800008dd1898
 #6 [ffff8001116ef8f0] handle_async_copy at ffff8000055142f4 [nfsv4]
 #7 [ffff8001116ef970] _nfs42_proc_copy at ffff8000055147c8 [nfsv4]
 torvalds#8 [ffff8001116efa80] nfs42_proc_copy at ffff800005514cf0 [nfsv4]
 torvalds#9 [ffff8001116efc50] __nfs4_copy_file_range.constprop.0 at ffff8000054ed694 [nfsv4]

The NULL-pointer dereference was due to nfs42_complete_copies() listed
the nfs_server->ss_copies by the field ss_copies of nfs4_copy_state.
So the nfs4_copy_state address ffff0100f98fa3f0 was offset by 0x10 and
the data accessed through this pointer was also incorrect. Generally,
the ordered list nfs4_state_owner->so_states indicate open(O_RDWR) or
open(O_WRITE) states are reclaimed firstly by nfs4_reclaim_open_state().
When destination state reclaim is failed with NFS_STATE_RECOVERY_FAILED
and copies are not deleted in nfs_server->ss_copies, the source state
may be passed to the nfs42_complete_copies() process earlier, resulting
in this crash scene finally. To solve this issue, we add a list_head
nfs_server->ss_src_copies for a server-to-server copy specially.

Fixes: 0e65a32 ("NFS: handle source server reboot")
Signed-off-by: Yanjun Zhang <zhangyanjun@cestc.cn>
Reviewed-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
tiwai pushed a commit that referenced this pull request Oct 25, 2024
Syzkaller reported a lockdep splat:

  ============================================
  WARNING: possible recursive locking detected
  6.11.0-rc6-syzkaller-00019-g67784a74e258 #0 Not tainted
  --------------------------------------------
  syz-executor364/5113 is trying to acquire lock:
  ffff8880449f1958 (k-slock-AF_INET){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
  ffff8880449f1958 (k-slock-AF_INET){+.-.}-{2:2}, at: sk_clone_lock+0x2cd/0xf40 net/core/sock.c:2328

  but task is already holding lock:
  ffff88803fe3cb58 (k-slock-AF_INET){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
  ffff88803fe3cb58 (k-slock-AF_INET){+.-.}-{2:2}, at: sk_clone_lock+0x2cd/0xf40 net/core/sock.c:2328

  other info that might help us debug this:
   Possible unsafe locking scenario:

         CPU0
         ----
    lock(k-slock-AF_INET);
    lock(k-slock-AF_INET);

   *** DEADLOCK ***

   May be due to missing lock nesting notation

  7 locks held by syz-executor364/5113:
   #0: ffff8880449f0e18 (sk_lock-AF_INET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1607 [inline]
   #0: ffff8880449f0e18 (sk_lock-AF_INET){+.+.}-{0:0}, at: mptcp_sendmsg+0x153/0x1b10 net/mptcp/protocol.c:1806
   #1: ffff88803fe39ad8 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1607 [inline]
   #1: ffff88803fe39ad8 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: mptcp_sendmsg_fastopen+0x11f/0x530 net/mptcp/protocol.c:1727
   #2: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline]
   #2: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
   #2: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: __ip_queue_xmit+0x5f/0x1b80 net/ipv4/ip_output.c:470
   #3: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline]
   #3: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
   #3: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: ip_finish_output2+0x45f/0x1390 net/ipv4/ip_output.c:228
   #4: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: local_lock_acquire include/linux/local_lock_internal.h:29 [inline]
   #4: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: process_backlog+0x33b/0x15b0 net/core/dev.c:6104
   #5: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline]
   #5: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
   #5: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: ip_local_deliver_finish+0x230/0x5f0 net/ipv4/ip_input.c:232
   #6: ffff88803fe3cb58 (k-slock-AF_INET){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
   #6: ffff88803fe3cb58 (k-slock-AF_INET){+.-.}-{2:2}, at: sk_clone_lock+0x2cd/0xf40 net/core/sock.c:2328

  stack backtrace:
  CPU: 0 UID: 0 PID: 5113 Comm: syz-executor364 Not tainted 6.11.0-rc6-syzkaller-00019-g67784a74e258 #0
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
  Call Trace:
   <IRQ>
   __dump_stack lib/dump_stack.c:93 [inline]
   dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119
   check_deadlock kernel/locking/lockdep.c:3061 [inline]
   validate_chain+0x15d3/0x5900 kernel/locking/lockdep.c:3855
   __lock_acquire+0x137a/0x2040 kernel/locking/lockdep.c:5142
   lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759
   __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
   _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
   spin_lock include/linux/spinlock.h:351 [inline]
   sk_clone_lock+0x2cd/0xf40 net/core/sock.c:2328
   mptcp_sk_clone_init+0x32/0x13c0 net/mptcp/protocol.c:3279
   subflow_syn_recv_sock+0x931/0x1920 net/mptcp/subflow.c:874
   tcp_check_req+0xfe4/0x1a20 net/ipv4/tcp_minisocks.c:853
   tcp_v4_rcv+0x1c3e/0x37f0 net/ipv4/tcp_ipv4.c:2267
   ip_protocol_deliver_rcu+0x22e/0x440 net/ipv4/ip_input.c:205
   ip_local_deliver_finish+0x341/0x5f0 net/ipv4/ip_input.c:233
   NF_HOOK+0x3a4/0x450 include/linux/netfilter.h:314
   NF_HOOK+0x3a4/0x450 include/linux/netfilter.h:314
   __netif_receive_skb_one_core net/core/dev.c:5661 [inline]
   __netif_receive_skb+0x2bf/0x650 net/core/dev.c:5775
   process_backlog+0x662/0x15b0 net/core/dev.c:6108
   __napi_poll+0xcb/0x490 net/core/dev.c:6772
   napi_poll net/core/dev.c:6841 [inline]
   net_rx_action+0x89b/0x1240 net/core/dev.c:6963
   handle_softirqs+0x2c4/0x970 kernel/softirq.c:554
   do_softirq+0x11b/0x1e0 kernel/softirq.c:455
   </IRQ>
   <TASK>
   __local_bh_enable_ip+0x1bb/0x200 kernel/softirq.c:382
   local_bh_enable include/linux/bottom_half.h:33 [inline]
   rcu_read_unlock_bh include/linux/rcupdate.h:908 [inline]
   __dev_queue_xmit+0x1763/0x3e90 net/core/dev.c:4450
   dev_queue_xmit include/linux/netdevice.h:3105 [inline]
   neigh_hh_output include/net/neighbour.h:526 [inline]
   neigh_output include/net/neighbour.h:540 [inline]
   ip_finish_output2+0xd41/0x1390 net/ipv4/ip_output.c:235
   ip_local_out net/ipv4/ip_output.c:129 [inline]
   __ip_queue_xmit+0x118c/0x1b80 net/ipv4/ip_output.c:535
   __tcp_transmit_skb+0x2544/0x3b30 net/ipv4/tcp_output.c:1466
   tcp_rcv_synsent_state_process net/ipv4/tcp_input.c:6542 [inline]
   tcp_rcv_state_process+0x2c32/0x4570 net/ipv4/tcp_input.c:6729
   tcp_v4_do_rcv+0x77d/0xc70 net/ipv4/tcp_ipv4.c:1934
   sk_backlog_rcv include/net/sock.h:1111 [inline]
   __release_sock+0x214/0x350 net/core/sock.c:3004
   release_sock+0x61/0x1f0 net/core/sock.c:3558
   mptcp_sendmsg_fastopen+0x1ad/0x530 net/mptcp/protocol.c:1733
   mptcp_sendmsg+0x1884/0x1b10 net/mptcp/protocol.c:1812
   sock_sendmsg_nosec net/socket.c:730 [inline]
   __sock_sendmsg+0x1a6/0x270 net/socket.c:745
   ____sys_sendmsg+0x525/0x7d0 net/socket.c:2597
   ___sys_sendmsg net/socket.c:2651 [inline]
   __sys_sendmmsg+0x3b2/0x740 net/socket.c:2737
   __do_sys_sendmmsg net/socket.c:2766 [inline]
   __se_sys_sendmmsg net/socket.c:2763 [inline]
   __x64_sys_sendmmsg+0xa0/0xb0 net/socket.c:2763
   do_syscall_x64 arch/x86/entry/common.c:52 [inline]
   do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
   entry_SYSCALL_64_after_hwframe+0x77/0x7f
  RIP: 0033:0x7f04fb13a6b9
  Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 01 1a 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
  RSP: 002b:00007ffd651f42d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
  RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f04fb13a6b9
  RDX: 0000000000000001 RSI: 0000000020000d00 RDI: 0000000000000004
  RBP: 00007ffd651f4310 R08: 0000000000000001 R09: 0000000000000001
  R10: 0000000020000080 R11: 0000000000000246 R12: 00000000000f4240
  R13: 00007f04fb187449 R14: 00007ffd651f42f4 R15: 00007ffd651f4300
   </TASK>

As noted by Cong Wang, the splat is false positive, but the code
path leading to the report is an unexpected one: a client is
attempting an MPC handshake towards the in-kernel listener created
by the in-kernel PM for a port based signal endpoint.

Such connection will be never accepted; many of them can make the
listener queue full and preventing the creation of MPJ subflow via
such listener - its intended role.

Explicitly detect this scenario at initial-syn time and drop the
incoming MPC request.

Fixes: 1729cf1 ("mptcp: create the listening socket for new port")
Cc: stable@vger.kernel.org
Reported-by: syzbot+f4aacdfef2c6a6529c3e@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=f4aacdfef2c6a6529c3e
Cc: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20241014-net-mptcp-mpc-port-endp-v2-1-7faea8e6b6ae@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
tiwai pushed a commit that referenced this pull request Nov 18, 2024
Hou Tao says:

====================
The patch set fixes several issues in bits iterator. Patch #1 fixes the
kmemleak problem of bits iterator. Patch #2~#3 fix the overflow problem
of nr_bits. Patch #4 fixes the potential stack corruption when bits
iterator is used on 32-bit host. Patch #5 adds more test cases for bits
iterator.

Please see the individual patches for more details. And comments are
always welcome.
---
v4:
 * patch #1: add ack from Yafang
 * patch #3: revert code-churn like changes:
   (1) compute nr_bytes and nr_bits before the check of nr_words.
   (2) use nr_bits == 64 to check for single u64, preventing build
       warning on 32-bit hosts.
 * patch #4: use "BITS_PER_LONG == 32" instead of "!defined(CONFIG_64BIT)"

v3: https://lore.kernel.org/bpf/20241025013233.804027-1-houtao@huaweicloud.com/T/#t
  * split the bits-iterator related patches from "Misc fixes for bpf"
    patch set
  * patch #1: use "!nr_bits || bits >= nr_bits" to stop the iteration
  * patch #2: add a new helper for the overflow problem
  * patch #3: decrease the limitation from 512 to 511 and check whether
    nr_bytes is too large for bpf memory allocator explicitly
  * patch #5: add two more test cases for bit iterator

v2: http://lore.kernel.org/bpf/d49fa2f4-f743-c763-7579-c3cab4dd88cb@huaweicloud.com
====================

Link: https://lore.kernel.org/r/20241030100516.3633640-1-houtao@huaweicloud.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
tiwai pushed a commit that referenced this pull request Nov 18, 2024
Petr Machata says:

====================
mlxsw: Fixes

In this patchset:

- Tx header should be pushed for each packet which is transmitted via
  Spectrum ASICs. Patch #1 adds a missing call to skb_cow_head() to make
  sure that there is both enough room to push the Tx header and that the
  SKB header is not cloned and can be modified.

- Commit b5b60bb ("mlxsw: pci: Use page pool for Rx buffers
  allocation") converted mlxsw to use page pool for Rx buffers allocation.
  Sync for CPU and for device should be done for Rx pages. In patches #2
  and #3, add the missing calls to sync pages for, respectively, CPU and
  the device.

- Patch #4 then fixes a bug to IPv6 GRE forwarding offload. Patch #5 adds
  a generic forwarding test that fails with mlxsw ports prior to the fix.
====================

Link: https://patch.msgid.link/cover.1729866134.git.petrm@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
tiwai pushed a commit that referenced this pull request Nov 20, 2024
When CONFIG_KASAN_SW_TAGS and CONFIG_KASAN_STACK are enabled, the
object_is_on_stack() function may produce incorrect results due to the
presence of tags in the obj pointer, while the stack pointer does not have
tags.  This discrepancy can lead to incorrect stack object detection and
subsequently trigger warnings if CONFIG_DEBUG_OBJECTS is also enabled.

Example of the warning:

ODEBUG: object 3eff800082ea7bb0 is NOT on stack ffff800082ea0000, but annotated.
------------[ cut here ]------------
WARNING: CPU: 0 PID: 1 at lib/debugobjects.c:557 __debug_object_init+0x330/0x364
Modules linked in:
CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.12.0-rc5 #4
Hardware name: linux,dummy-virt (DT)
pstate: 600000c5 (nZCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : __debug_object_init+0x330/0x364
lr : __debug_object_init+0x330/0x364
sp : ffff800082ea7b40
x29: ffff800082ea7b40 x28: 98ff0000c0164518 x27: 98ff0000c0164534
x26: ffff800082d93ec8 x25: 0000000000000001 x24: 1cff0000c00172a0
x23: 0000000000000000 x22: ffff800082d93ed0 x21: ffff800081a24418
x20: 3eff800082ea7bb0 x19: efff800000000000 x18: 0000000000000000
x17: 00000000000000ff x16: 0000000000000047 x15: 206b63617473206e
x14: 0000000000000018 x13: ffff800082ea7780 x12: 0ffff800082ea78e
x11: 0ffff800082ea790 x10: 0ffff800082ea79d x9 : 34d77febe173e800
x8 : 34d77febe173e800 x7 : 0000000000000001 x6 : 0000000000000001
x5 : feff800082ea74b8 x4 : ffff800082870a90 x3 : ffff80008018d3c4
x2 : 0000000000000001 x1 : ffff800082858810 x0 : 0000000000000050
Call trace:
 __debug_object_init+0x330/0x364
 debug_object_init_on_stack+0x30/0x3c
 schedule_hrtimeout_range_clock+0xac/0x26c
 schedule_hrtimeout+0x1c/0x30
 wait_task_inactive+0x1d4/0x25c
 kthread_bind_mask+0x28/0x98
 init_rescuer+0x1e8/0x280
 workqueue_init+0x1a0/0x3cc
 kernel_init_freeable+0x118/0x200
 kernel_init+0x28/0x1f0
 ret_from_fork+0x10/0x20
---[ end trace 0000000000000000 ]---
ODEBUG: object 3eff800082ea7bb0 is NOT on stack ffff800082ea0000, but annotated.
------------[ cut here ]------------

Link: https://lkml.kernel.org/r/20241113042544.19095-1-qun-wei.lin@mediatek.com
Signed-off-by: Qun-Wei Lin <qun-wei.lin@mediatek.com>
Cc: Andrew Yang <andrew.yang@mediatek.com>
Cc: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Cc: Casper Li <casper.li@mediatek.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chinwen Chang <chinwen.chang@mediatek.com>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
tiwai pushed a commit that referenced this pull request Dec 12, 2024
Kernel will hang on destroy admin_q while we create ctrl failed, such
as following calltrace:

PID: 23644    TASK: ff2d52b40f439fc0  CPU: 2    COMMAND: "nvme"
 #0 [ff61d23de260fb78] __schedule at ffffffff8323bc15
 #1 [ff61d23de260fc08] schedule at ffffffff8323c014
 #2 [ff61d23de260fc28] blk_mq_freeze_queue_wait at ffffffff82a3dba1
 #3 [ff61d23de260fc78] blk_freeze_queue at ffffffff82a4113a
 #4 [ff61d23de260fc90] blk_cleanup_queue at ffffffff82a33006
 #5 [ff61d23de260fcb0] nvme_rdma_destroy_admin_queue at ffffffffc12686ce
 #6 [ff61d23de260fcc8] nvme_rdma_setup_ctrl at ffffffffc1268ced
 #7 [ff61d23de260fd28] nvme_rdma_create_ctrl at ffffffffc126919b
 torvalds#8 [ff61d23de260fd68] nvmf_dev_write at ffffffffc024f362
 torvalds#9 [ff61d23de260fe38] vfs_write at ffffffff827d5f25
    RIP: 00007fda7891d574  RSP: 00007ffe2ef06958  RFLAGS: 00000202
    RAX: ffffffffffffffda  RBX: 000055e8122a4d90  RCX: 00007fda7891d574
    RDX: 000000000000012b  RSI: 000055e8122a4d90  RDI: 0000000000000004
    RBP: 00007ffe2ef079c0   R8: 000000000000012b   R9: 000055e8122a4d90
    R10: 0000000000000000  R11: 0000000000000202  R12: 0000000000000004
    R13: 000055e8122923c0  R14: 000000000000012b  R15: 00007fda78a54500
    ORIG_RAX: 0000000000000001  CS: 0033  SS: 002b

This due to we have quiesced admi_q before cancel requests, but forgot
to unquiesce before destroy it, as a result we fail to drain the
pending requests, and hang on blk_mq_freeze_queue_wait() forever. Here
try to reuse nvme_rdma_teardown_admin_queue() to fix this issue and
simplify the code.

Fixes: 958dc1d ("nvme-rdma: add clean action for failed reconnection")
Reported-by: Yingfu.zhou <yingfu.zhou@shopee.com>
Signed-off-by: Chunguang.xu <chunguang.xu@shopee.com>
Signed-off-by: Yue.zhao <yue.zhao@shopee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>
tiwai pushed a commit that referenced this pull request Dec 12, 2024
Hou Tao says:

====================
This patch set fixes several issues for LPM trie. These issues were
found during adding new test cases or were reported by syzbot.

The patch set is structured as follows:

Patch #1~#2 are clean-ups for lpm_trie_update_elem().
Patch #3 handles BPF_EXIST and BPF_NOEXIST correctly for LPM trie.
Patch #4 fixes the accounting of n_entries when doing in-place update.
Patch #5 fixes the exact match condition in trie_get_next_key() and it
may skip keys when the passed key is not found in the map.
Patch #6~#7 switch from kmalloc() to bpf memory allocator for LPM trie
to fix several lock order warnings reported by syzbot. It also enables
raw_spinlock_t for LPM trie again. After these changes, the LPM trie will
be closer to being usable in any context (though the reentrance check of
trie->lock is still missing, but it is on my todo list).
Patch torvalds#8: move test_lpm_map to map_tests to make it run regularly.
Patch torvalds#9: add test cases for the issues fixed by patch #3~#5.

Please see individual patches for more details. Comments are always
welcome.

Change Log:
v3:
  * patch #2: remove the unnecessary NULL-init for im_node
  * patch #6: alloc the leaf node before disabling IRQ to low
    the possibility of -ENOMEM when leaf_size is large; Free
    these nodes outside the trie lock (Suggested by Alexei)
  * collect review and ack tags (Thanks for Toke & Daniel)

v2: https://lore.kernel.org/bpf/20241127004641.1118269-1-houtao@huaweicloud.com/
  * collect review tags (Thanks for Toke)
  * drop "Add bpf_mem_cache_is_mergeable() helper" patch
  * patch #3~#4: add fix tag
  * patch #4: rename the helper to trie_check_add_elem() and increase
    n_entries in it.
  * patch #6: use one bpf mem allocator and update commit message to
    clarify that using bpf mem allocator is more appropriate.
  * patch #7: update commit message to add the possible max running time
    for update operation.
  * patch torvalds#9: update commit message to specify the purpose of these test
    cases.

v1: https://lore.kernel.org/bpf/20241118010808.2243555-1-houtao@huaweicloud.com/
====================

Link: https://lore.kernel.org/all/20241206110622.1161752-1-houtao@huaweicloud.com/
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
tiwai pushed a commit that referenced this pull request Dec 20, 2024
Its used from trace__run(), for the 'perf trace' live mode, i.e. its
strace-like, non-perf.data file processing mode, the most common one.

The trace__run() function will set trace->host using machine__new_host()
that is supposed to give a machine instance representing the running
machine, and since we'll use perf_env__arch_strerrno() to get the right
errno -> string table, we need to use machine->env, so initialize it in
machine__new_host().

Before the patch:

  (gdb) run trace --errno-summary -a sleep 1
  <SNIP>
   Summary of events:

   gvfs-afc-volume (3187), 2 events, 0.0%

     syscall            calls  errors  total       min       avg       max       stddev
                                       (msec)    (msec)    (msec)    (msec)        (%)
     --------------- --------  ------ -------- --------- --------- ---------     ------
     pselect6               1      0     0.000     0.000     0.000     0.000      0.00%

   GUsbEventThread (3519), 2 events, 0.0%

     syscall            calls  errors  total       min       avg       max       stddev
                                       (msec)    (msec)    (msec)    (msec)        (%)
     --------------- --------  ------ -------- --------- --------- ---------     ------
     poll                   1      0     0.000     0.000     0.000     0.000      0.00%
  <SNIP>
  Program received signal SIGSEGV, Segmentation fault.
  0x00000000005caba0 in perf_env__arch_strerrno (env=0x0, err=110) at util/env.c:478
  478		if (env->arch_strerrno == NULL)
  (gdb) bt
  #0  0x00000000005caba0 in perf_env__arch_strerrno (env=0x0, err=110) at util/env.c:478
  #1  0x00000000004b75d2 in thread__dump_stats (ttrace=0x14f58f0, trace=0x7fffffffa5b0, fp=0x7ffff6ff74e0 <_IO_2_1_stderr_>) at builtin-trace.c:4673
  #2  0x00000000004b78bf in trace__fprintf_thread (fp=0x7ffff6ff74e0 <_IO_2_1_stderr_>, thread=0x10fa0b0, trace=0x7fffffffa5b0) at builtin-trace.c:4708
  #3  0x00000000004b7ad9 in trace__fprintf_thread_summary (trace=0x7fffffffa5b0, fp=0x7ffff6ff74e0 <_IO_2_1_stderr_>) at builtin-trace.c:4747
  #4  0x00000000004b656e in trace__run (trace=0x7fffffffa5b0, argc=2, argv=0x7fffffffde60) at builtin-trace.c:4456
  #5  0x00000000004ba43e in cmd_trace (argc=2, argv=0x7fffffffde60) at builtin-trace.c:5487
  #6  0x00000000004c0414 in run_builtin (p=0xec3068 <commands+648>, argc=5, argv=0x7fffffffde60) at perf.c:351
  #7  0x00000000004c06bb in handle_internal_command (argc=5, argv=0x7fffffffde60) at perf.c:404
  torvalds#8  0x00000000004c0814 in run_argv (argcp=0x7fffffffdc4c, argv=0x7fffffffdc40) at perf.c:448
  torvalds#9  0x00000000004c0b5d in main (argc=5, argv=0x7fffffffde60) at perf.c:560
  (gdb)

After:

  root@number:~# perf trace -a --errno-summary sleep 1
  <SNIP>
     pw-data-loop (2685), 1410 events, 16.0%

     syscall            calls  errors  total       min       avg       max       stddev
                                       (msec)    (msec)    (msec)    (msec)        (%)
     --------------- --------  ------ -------- --------- --------- ---------     ------
     epoll_wait           188      0   983.428     0.000     5.231    15.595      8.68%
     ioctl                 94      0     0.811     0.004     0.009     0.016      2.82%
     read                 188      0     0.322     0.001     0.002     0.006      5.15%
     write                141      0     0.280     0.001     0.002     0.018      8.39%
     timerfd_settime       94      0     0.138     0.001     0.001     0.007      6.47%

   gnome-control-c (179406), 1848 events, 20.9%

     syscall            calls  errors  total       min       avg       max       stddev
                                       (msec)    (msec)    (msec)    (msec)        (%)
     --------------- --------  ------ -------- --------- --------- ---------     ------
     poll                 222      0   959.577     0.000     4.322    21.414     11.40%
     recvmsg              150      0     0.539     0.001     0.004     0.013      5.12%
     write                300      0     0.442     0.001     0.001     0.007      3.29%
     read                 150      0     0.183     0.001     0.001     0.009      5.53%
     getpid               102      0     0.101     0.000     0.001     0.008      7.82%

  root@number:~#

Fixes: 54373b5 ("perf env: Introduce perf_env__arch_strerrno()")
Reported-by: Veronika Molnarova <vmolnaro@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Veronika Molnarova <vmolnaro@redhat.com>
Acked-by: Michael Petlan <mpetlan@redhat.com>
Tested-by: Michael Petlan <mpetlan@redhat.com>
Link: https://lore.kernel.org/r/Z0XffUgNSv_9OjOi@x1
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
tiwai pushed a commit that referenced this pull request Dec 20, 2024
…s_lock

For storing a value to a queue attribute, the queue_attr_store function
first freezes the queue (->q_usage_counter(io)) and then acquire
->sysfs_lock. This seems not correct as the usual ordering should be to
acquire ->sysfs_lock before freezing the queue. This incorrect ordering
causes the following lockdep splat which we are able to reproduce always
simply by accessing /sys/kernel/debug file using ls command:

[   57.597146] WARNING: possible circular locking dependency detected
[   57.597154] 6.12.0-10553-gb86545e02e8c torvalds#20 Tainted: G        W
[   57.597162] ------------------------------------------------------
[   57.597168] ls/4605 is trying to acquire lock:
[   57.597176] c00000003eb56710 (&mm->mmap_lock){++++}-{4:4}, at: __might_fault+0x58/0xc0
[   57.597200]
               but task is already holding lock:
[   57.597207] c0000018e27c6810 (&sb->s_type->i_mutex_key#3){++++}-{4:4}, at: iterate_dir+0x94/0x1d4
[   57.597226]
               which lock already depends on the new lock.

[   57.597233]
               the existing dependency chain (in reverse order) is:
[   57.597241]
               -> #5 (&sb->s_type->i_mutex_key#3){++++}-{4:4}:
[   57.597255]        down_write+0x6c/0x18c
[   57.597264]        start_creating+0xb4/0x24c
[   57.597274]        debugfs_create_dir+0x2c/0x1e8
[   57.597283]        blk_register_queue+0xec/0x294
[   57.597292]        add_disk_fwnode+0x2e4/0x548
[   57.597302]        brd_alloc+0x2c8/0x338
[   57.597309]        brd_init+0x100/0x178
[   57.597317]        do_one_initcall+0x88/0x3e4
[   57.597326]        kernel_init_freeable+0x3cc/0x6e0
[   57.597334]        kernel_init+0x34/0x1cc
[   57.597342]        ret_from_kernel_user_thread+0x14/0x1c
[   57.597350]
               -> #4 (&q->debugfs_mutex){+.+.}-{4:4}:
[   57.597362]        __mutex_lock+0xfc/0x12a0
[   57.597370]        blk_register_queue+0xd4/0x294
[   57.597379]        add_disk_fwnode+0x2e4/0x548
[   57.597388]        brd_alloc+0x2c8/0x338
[   57.597395]        brd_init+0x100/0x178
[   57.597402]        do_one_initcall+0x88/0x3e4
[   57.597410]        kernel_init_freeable+0x3cc/0x6e0
[   57.597418]        kernel_init+0x34/0x1cc
[   57.597426]        ret_from_kernel_user_thread+0x14/0x1c
[   57.597434]
               -> #3 (&q->sysfs_lock){+.+.}-{4:4}:
[   57.597446]        __mutex_lock+0xfc/0x12a0
[   57.597454]        queue_attr_store+0x9c/0x110
[   57.597462]        sysfs_kf_write+0x70/0xb0
[   57.597471]        kernfs_fop_write_iter+0x1b0/0x2ac
[   57.597480]        vfs_write+0x3dc/0x6e8
[   57.597488]        ksys_write+0x84/0x140
[   57.597495]        system_call_exception+0x130/0x360
[   57.597504]        system_call_common+0x160/0x2c4
[   57.597516]
               -> #2 (&q->q_usage_counter(io)torvalds#21){++++}-{0:0}:
[   57.597530]        __submit_bio+0x5ec/0x828
[   57.597538]        submit_bio_noacct_nocheck+0x1e4/0x4f0
[   57.597547]        iomap_readahead+0x2a0/0x448
[   57.597556]        xfs_vm_readahead+0x28/0x3c
[   57.597564]        read_pages+0x88/0x41c
[   57.597571]        page_cache_ra_unbounded+0x1ac/0x2d8
[   57.597580]        filemap_get_pages+0x188/0x984
[   57.597588]        filemap_read+0x13c/0x4bc
[   57.597596]        xfs_file_buffered_read+0x88/0x17c
[   57.597605]        xfs_file_read_iter+0xac/0x158
[   57.597614]        vfs_read+0x2d4/0x3b4
[   57.597622]        ksys_read+0x84/0x144
[   57.597629]        system_call_exception+0x130/0x360
[   57.597637]        system_call_common+0x160/0x2c4
[   57.597647]
               -> #1 (mapping.invalidate_lock#2){++++}-{4:4}:
[   57.597661]        down_read+0x6c/0x220
[   57.597669]        filemap_fault+0x870/0x100c
[   57.597677]        xfs_filemap_fault+0xc4/0x18c
[   57.597684]        __do_fault+0x64/0x164
[   57.597693]        __handle_mm_fault+0x1274/0x1dac
[   57.597702]        handle_mm_fault+0x248/0x484
[   57.597711]        ___do_page_fault+0x428/0xc0c
[   57.597719]        hash__do_page_fault+0x30/0x68
[   57.597727]        do_hash_fault+0x90/0x35c
[   57.597736]        data_access_common_virt+0x210/0x220
[   57.597745]        _copy_from_user+0xf8/0x19c
[   57.597754]        sel_write_load+0x178/0xd54
[   57.597762]        vfs_write+0x108/0x6e8
[   57.597769]        ksys_write+0x84/0x140
[   57.597777]        system_call_exception+0x130/0x360
[   57.597785]        system_call_common+0x160/0x2c4
[   57.597794]
               -> #0 (&mm->mmap_lock){++++}-{4:4}:
[   57.597806]        __lock_acquire+0x17cc/0x2330
[   57.597814]        lock_acquire+0x138/0x400
[   57.597822]        __might_fault+0x7c/0xc0
[   57.597830]        filldir64+0xe8/0x390
[   57.597839]        dcache_readdir+0x80/0x2d4
[   57.597846]        iterate_dir+0xd8/0x1d4
[   57.597855]        sys_getdents64+0x88/0x2d4
[   57.597864]        system_call_exception+0x130/0x360
[   57.597872]        system_call_common+0x160/0x2c4
[   57.597881]
               other info that might help us debug this:

[   57.597888] Chain exists of:
                 &mm->mmap_lock --> &q->debugfs_mutex --> &sb->s_type->i_mutex_key#3

[   57.597905]  Possible unsafe locking scenario:

[   57.597911]        CPU0                    CPU1
[   57.597917]        ----                    ----
[   57.597922]   rlock(&sb->s_type->i_mutex_key#3);
[   57.597932]                                lock(&q->debugfs_mutex);
[   57.597940]                                lock(&sb->s_type->i_mutex_key#3);
[   57.597950]   rlock(&mm->mmap_lock);
[   57.597958]
                *** DEADLOCK ***

[   57.597965] 2 locks held by ls/4605:
[   57.597971]  #0: c0000000137c12f8 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0xcc/0x154
[   57.597989]  #1: c0000018e27c6810 (&sb->s_type->i_mutex_key#3){++++}-{4:4}, at: iterate_dir+0x94/0x1d4

Prevent the above lockdep warning by acquiring ->sysfs_lock before
freezing the queue while storing a queue attribute in queue_attr_store
function. Later, we also found[1] another function __blk_mq_update_nr_
hw_queues where we first freeze queue and then acquire the ->sysfs_lock.
So we've also updated lock ordering in __blk_mq_update_nr_hw_queues
function and ensured that in all code paths we follow the correct lock
ordering i.e. acquire ->sysfs_lock before freezing the queue.

[1] https://lore.kernel.org/all/CAFj5m9Ke8+EHKQBs_Nk6hqd=LGXtk4mUxZUN5==ZcCjnZSBwHw@mail.gmail.com/

Reported-by: kjain@linux.ibm.com
Fixes: af28141 ("block: freeze the queue in queue_attr_store")
Tested-by: kjain@linux.ibm.com
Cc: hch@lst.de
Cc: axboe@kernel.dk
Cc: ritesh.list@gmail.com
Cc: ming.lei@redhat.com
Cc: gjoyce@linux.ibm.com
Signed-off-by: Nilay Shroff <nilay@linux.ibm.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20241210144222.1066229-1-nilay@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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