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[docs] - linux/documentation/abi/readme - minor tweaks [writing] #508
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###### [docs] - linux/documentation/abi/readme - minor tweaks [writing]
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The new tests replicate the tests done for ARG_PTR_TO_LONG. There is a missing test for the "size < sizeof(long)" case, because I'm not sure I understand what this test is about and how to replicate it with bpf_sk_get_netns. An output of the tests: torvalds#508/p ARG_PTR_TO_LONG_OR_NULL uninitialized OK torvalds#509/p ARG_PTR_TO_LONG_OR_NULL half-uninitialized OK torvalds#510/p ARG_PTR_TO_LONG_OR_NULL misaligned OK torvalds#511/p ARG_PTR_TO_LONG_OR_NULL initialized OK torvalds#512/p ARG_PTR_TO_LONG_OR_NULL initialized to NULL OK Signed-off-by: Krzesimir Nowak <krzesimir@kinvolk.io>
commit 7bc9491 upstream. Although the extent tree depth of 5 should enough be for the worst case of 2*32 extents of length 1, the extent tree code does not currently to merge nodes which are less than half-full with a sibling node, or to shrink the tree depth if possible. So it's possible, at least in theory, for the tree depth to be greater than 5. However, even in the worst case, a tree depth of 32 is highly unlikely, and if the file system is maliciously corrupted, an insanely large eh_depth can cause memory allocation failures that will trigger kernel warnings (here, eh_depth = 65280): JBD2: ext4.exe wants too many credits credits:195849 rsv_credits:0 max:256 ------------[ cut here ]------------ WARNING: CPU: 0 PID: 50 at fs/jbd2/transaction.c:293 start_this_handle+0x569/0x580 CPU: 0 PID: 50 Comm: ext4.exe Not tainted 4.7.0-rc5+ torvalds#508 Stack: 604a8947 625badd8 0002fd09 00000000 60078643 00000000 62623910 601bf9bc 62623970 6002fc84 626239b0 900000125 Call Trace: [<6001c2dc>] show_stack+0xdc/0x1a0 [<601bf9bc>] dump_stack+0x2a/0x2e [<6002fc84>] __warn+0x114/0x140 [<6002fdff>] warn_slowpath_null+0x1f/0x30 [<60165829>] start_this_handle+0x569/0x580 [<60165d4e>] jbd2__journal_start+0x11e/0x220 [<60146690>] __ext4_journal_start_sb+0x60/0xa0 [<60120a81>] ext4_truncate+0x131/0x3a0 [<60123677>] ext4_setattr+0x757/0x840 [<600d5d0f>] notify_change+0x16f/0x2a0 [<600b2b16>] do_truncate+0x76/0xc0 [<600c3e56>] path_openat+0x806/0x1300 [<600c55c9>] do_filp_open+0x89/0xf0 [<600b4074>] do_sys_open+0x134/0x1e0 [<600b4140>] SyS_open+0x20/0x30 [<6001ea68>] handle_syscall+0x88/0x90 [<600295fd>] userspace+0x3fd/0x500 [<6001ac55>] fork_handler+0x85/0x90 ---[ end trace 08b0b88b6387a244 ]--- [ Commit message modified and the extent tree depath check changed from 5 to 32 -- tytso ] Cc: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Lee Jones <lee.jones@linaro.org> Change-Id: Ib24906e8b0b7cc74887569492c84da17ba85359d
…checkpatch-fixes WARNING: please, no space before tabs torvalds#506: FILE: mm/gup.c:1513: +^I * ^I the page dirty with FOLL_WRITE -- which doesn't make a$ WARNING: please, no space before tabs torvalds#507: FILE: mm/gup.c:1514: +^I * ^I difference with !FOLL_FORCE, because the page is writable$ WARNING: please, no space before tabs torvalds#508: FILE: mm/gup.c:1515: +^I * ^I in the page table.$ total: 0 errors, 3 warnings, 214 lines checked NOTE: For some of the reported defects, checkpatch may be able to mechanically convert to the typical style using --fix or --fix-inplace. ./patches/mm-madvise-introduce-madv_populate_readwrite-to-prefault-page-tables.patch has style problems, please review. NOTE: If any of the errors are false positives, please report them to the maintainer, see CHECKPATCH in MAINTAINERS. Please run checkpatch prior to sending patches Cc: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
…checkpatch-fixes WARNING: please, no space before tabs torvalds#506: FILE: mm/gup.c:1513: +^I * ^I the page dirty with FOLL_WRITE -- which doesn't make a$ WARNING: please, no space before tabs torvalds#507: FILE: mm/gup.c:1514: +^I * ^I difference with !FOLL_FORCE, because the page is writable$ WARNING: please, no space before tabs torvalds#508: FILE: mm/gup.c:1515: +^I * ^I in the page table.$ total: 0 errors, 3 warnings, 214 lines checked NOTE: For some of the reported defects, checkpatch may be able to mechanically convert to the typical style using --fix or --fix-inplace. ./patches/mm-madvise-introduce-madv_populate_readwrite-to-prefault-page-tables.patch has style problems, please review. NOTE: If any of the errors are false positives, please report them to the maintainer, see CHECKPATCH in MAINTAINERS. Please run checkpatch prior to sending patches Cc: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
…checkpatch-fixes WARNING: please, no space before tabs torvalds#506: FILE: mm/gup.c:1513: +^I * ^I the page dirty with FOLL_WRITE -- which doesn't make a$ WARNING: please, no space before tabs torvalds#507: FILE: mm/gup.c:1514: +^I * ^I difference with !FOLL_FORCE, because the page is writable$ WARNING: please, no space before tabs torvalds#508: FILE: mm/gup.c:1515: +^I * ^I in the page table.$ total: 0 errors, 3 warnings, 214 lines checked NOTE: For some of the reported defects, checkpatch may be able to mechanically convert to the typical style using --fix or --fix-inplace. ./patches/mm-madvise-introduce-madv_populate_readwrite-to-prefault-page-tables.patch has style problems, please review. NOTE: If any of the errors are false positives, please report them to the maintainer, see CHECKPATCH in MAINTAINERS. Please run checkpatch prior to sending patches Cc: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
…checkpatch-fixes WARNING: please, no space before tabs torvalds#506: FILE: mm/gup.c:1513: +^I * ^I the page dirty with FOLL_WRITE -- which doesn't make a$ WARNING: please, no space before tabs torvalds#507: FILE: mm/gup.c:1514: +^I * ^I difference with !FOLL_FORCE, because the page is writable$ WARNING: please, no space before tabs torvalds#508: FILE: mm/gup.c:1515: +^I * ^I in the page table.$ total: 0 errors, 3 warnings, 214 lines checked NOTE: For some of the reported defects, checkpatch may be able to mechanically convert to the typical style using --fix or --fix-inplace. ./patches/mm-madvise-introduce-madv_populate_readwrite-to-prefault-page-tables.patch has style problems, please review. NOTE: If any of the errors are false positives, please report them to the maintainer, see CHECKPATCH in MAINTAINERS. Please run checkpatch prior to sending patches Cc: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
…checkpatch-fixes WARNING: please, no space before tabs torvalds#506: FILE: mm/gup.c:1513: +^I * ^I the page dirty with FOLL_WRITE -- which doesn't make a$ WARNING: please, no space before tabs torvalds#507: FILE: mm/gup.c:1514: +^I * ^I difference with !FOLL_FORCE, because the page is writable$ WARNING: please, no space before tabs torvalds#508: FILE: mm/gup.c:1515: +^I * ^I in the page table.$ total: 0 errors, 3 warnings, 214 lines checked NOTE: For some of the reported defects, checkpatch may be able to mechanically convert to the typical style using --fix or --fix-inplace. ./patches/mm-madvise-introduce-madv_populate_readwrite-to-prefault-page-tables.patch has style problems, please review. NOTE: If any of the errors are false positives, please report them to the maintainer, see CHECKPATCH in MAINTAINERS. Please run checkpatch prior to sending patches Cc: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
…checkpatch-fixes WARNING: please, no space before tabs torvalds#506: FILE: mm/gup.c:1513: +^I * ^I the page dirty with FOLL_WRITE -- which doesn't make a$ WARNING: please, no space before tabs torvalds#507: FILE: mm/gup.c:1514: +^I * ^I difference with !FOLL_FORCE, because the page is writable$ WARNING: please, no space before tabs torvalds#508: FILE: mm/gup.c:1515: +^I * ^I in the page table.$ total: 0 errors, 3 warnings, 214 lines checked NOTE: For some of the reported defects, checkpatch may be able to mechanically convert to the typical style using --fix or --fix-inplace. ./patches/mm-madvise-introduce-madv_populate_readwrite-to-prefault-page-tables.patch has style problems, please review. NOTE: If any of the errors are false positives, please report them to the maintainer, see CHECKPATCH in MAINTAINERS. Please run checkpatch prior to sending patches Cc: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
…checkpatch-fixes WARNING: please, no space before tabs torvalds#506: FILE: mm/gup.c:1513: +^I * ^I the page dirty with FOLL_WRITE -- which doesn't make a$ WARNING: please, no space before tabs torvalds#507: FILE: mm/gup.c:1514: +^I * ^I difference with !FOLL_FORCE, because the page is writable$ WARNING: please, no space before tabs torvalds#508: FILE: mm/gup.c:1515: +^I * ^I in the page table.$ total: 0 errors, 3 warnings, 214 lines checked NOTE: For some of the reported defects, checkpatch may be able to mechanically convert to the typical style using --fix or --fix-inplace. ./patches/mm-madvise-introduce-madv_populate_readwrite-to-prefault-page-tables.patch has style problems, please review. NOTE: If any of the errors are false positives, please report them to the maintainer, see CHECKPATCH in MAINTAINERS. Please run checkpatch prior to sending patches Cc: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
…checkpatch-fixes WARNING: please, no space before tabs torvalds#506: FILE: mm/gup.c:1513: +^I * ^I the page dirty with FOLL_WRITE -- which doesn't make a$ WARNING: please, no space before tabs torvalds#507: FILE: mm/gup.c:1514: +^I * ^I difference with !FOLL_FORCE, because the page is writable$ WARNING: please, no space before tabs torvalds#508: FILE: mm/gup.c:1515: +^I * ^I in the page table.$ total: 0 errors, 3 warnings, 214 lines checked NOTE: For some of the reported defects, checkpatch may be able to mechanically convert to the typical style using --fix or --fix-inplace. ./patches/mm-madvise-introduce-madv_populate_readwrite-to-prefault-page-tables.patch has style problems, please review. NOTE: If any of the errors are false positives, please report them to the maintainer, see CHECKPATCH in MAINTAINERS. Please run checkpatch prior to sending patches Cc: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
…checkpatch-fixes WARNING: please, no space before tabs torvalds#506: FILE: mm/gup.c:1513: +^I * ^I the page dirty with FOLL_WRITE -- which doesn't make a$ WARNING: please, no space before tabs torvalds#507: FILE: mm/gup.c:1514: +^I * ^I difference with !FOLL_FORCE, because the page is writable$ WARNING: please, no space before tabs torvalds#508: FILE: mm/gup.c:1515: +^I * ^I in the page table.$ total: 0 errors, 3 warnings, 214 lines checked NOTE: For some of the reported defects, checkpatch may be able to mechanically convert to the typical style using --fix or --fix-inplace. ./patches/mm-madvise-introduce-madv_populate_readwrite-to-prefault-page-tables.patch has style problems, please review. NOTE: If any of the errors are false positives, please report them to the maintainer, see CHECKPATCH in MAINTAINERS. Please run checkpatch prior to sending patches Cc: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
…checkpatch-fixes WARNING: please, no space before tabs torvalds#506: FILE: mm/gup.c:1513: +^I * ^I the page dirty with FOLL_WRITE -- which doesn't make a$ WARNING: please, no space before tabs torvalds#507: FILE: mm/gup.c:1514: +^I * ^I difference with !FOLL_FORCE, because the page is writable$ WARNING: please, no space before tabs torvalds#508: FILE: mm/gup.c:1515: +^I * ^I in the page table.$ total: 0 errors, 3 warnings, 214 lines checked NOTE: For some of the reported defects, checkpatch may be able to mechanically convert to the typical style using --fix or --fix-inplace. ./patches/mm-madvise-introduce-madv_populate_readwrite-to-prefault-page-tables.patch has style problems, please review. NOTE: If any of the errors are false positives, please report them to the maintainer, see CHECKPATCH in MAINTAINERS. Please run checkpatch prior to sending patches Cc: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
…checkpatch-fixes WARNING: please, no space before tabs torvalds#506: FILE: mm/gup.c:1513: +^I * ^I the page dirty with FOLL_WRITE -- which doesn't make a$ WARNING: please, no space before tabs torvalds#507: FILE: mm/gup.c:1514: +^I * ^I difference with !FOLL_FORCE, because the page is writable$ WARNING: please, no space before tabs torvalds#508: FILE: mm/gup.c:1515: +^I * ^I in the page table.$ total: 0 errors, 3 warnings, 214 lines checked NOTE: For some of the reported defects, checkpatch may be able to mechanically convert to the typical style using --fix or --fix-inplace. ./patches/mm-madvise-introduce-madv_populate_readwrite-to-prefault-page-tables.patch has style problems, please review. NOTE: If any of the errors are false positives, please report them to the maintainer, see CHECKPATCH in MAINTAINERS. Please run checkpatch prior to sending patches Cc: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
…checkpatch-fixes WARNING: please, no space before tabs torvalds#506: FILE: mm/gup.c:1513: +^I * ^I the page dirty with FOLL_WRITE -- which doesn't make a$ WARNING: please, no space before tabs torvalds#507: FILE: mm/gup.c:1514: +^I * ^I difference with !FOLL_FORCE, because the page is writable$ WARNING: please, no space before tabs torvalds#508: FILE: mm/gup.c:1515: +^I * ^I in the page table.$ total: 0 errors, 3 warnings, 214 lines checked NOTE: For some of the reported defects, checkpatch may be able to mechanically convert to the typical style using --fix or --fix-inplace. ./patches/mm-madvise-introduce-madv_populate_readwrite-to-prefault-page-tables.patch has style problems, please review. NOTE: If any of the errors are false positives, please report them to the maintainer, see CHECKPATCH in MAINTAINERS. Please run checkpatch prior to sending patches Cc: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
…checkpatch-fixes WARNING: please, no space before tabs torvalds#506: FILE: mm/gup.c:1513: +^I * ^I the page dirty with FOLL_WRITE -- which doesn't make a$ WARNING: please, no space before tabs torvalds#507: FILE: mm/gup.c:1514: +^I * ^I difference with !FOLL_FORCE, because the page is writable$ WARNING: please, no space before tabs torvalds#508: FILE: mm/gup.c:1515: +^I * ^I in the page table.$ total: 0 errors, 3 warnings, 214 lines checked NOTE: For some of the reported defects, checkpatch may be able to mechanically convert to the typical style using --fix or --fix-inplace. ./patches/mm-madvise-introduce-madv_populate_readwrite-to-prefault-page-tables.patch has style problems, please review. NOTE: If any of the errors are false positives, please report them to the maintainer, see CHECKPATCH in MAINTAINERS. Please run checkpatch prior to sending patches Cc: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
…checkpatch-fixes WARNING: please, no space before tabs torvalds#506: FILE: mm/gup.c:1513: +^I * ^I the page dirty with FOLL_WRITE -- which doesn't make a$ WARNING: please, no space before tabs torvalds#507: FILE: mm/gup.c:1514: +^I * ^I difference with !FOLL_FORCE, because the page is writable$ WARNING: please, no space before tabs torvalds#508: FILE: mm/gup.c:1515: +^I * ^I in the page table.$ total: 0 errors, 3 warnings, 214 lines checked NOTE: For some of the reported defects, checkpatch may be able to mechanically convert to the typical style using --fix or --fix-inplace. ./patches/mm-madvise-introduce-madv_populate_readwrite-to-prefault-page-tables.patch has style problems, please review. NOTE: If any of the errors are false positives, please report them to the maintainer, see CHECKPATCH in MAINTAINERS. Please run checkpatch prior to sending patches Cc: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
…checkpatch-fixes WARNING: please, no space before tabs torvalds#506: FILE: mm/gup.c:1513: +^I * ^I the page dirty with FOLL_WRITE -- which doesn't make a$ WARNING: please, no space before tabs torvalds#507: FILE: mm/gup.c:1514: +^I * ^I difference with !FOLL_FORCE, because the page is writable$ WARNING: please, no space before tabs torvalds#508: FILE: mm/gup.c:1515: +^I * ^I in the page table.$ total: 0 errors, 3 warnings, 214 lines checked NOTE: For some of the reported defects, checkpatch may be able to mechanically convert to the typical style using --fix or --fix-inplace. ./patches/mm-madvise-introduce-madv_populate_readwrite-to-prefault-page-tables.patch has style problems, please review. NOTE: If any of the errors are false positives, please report them to the maintainer, see CHECKPATCH in MAINTAINERS. Please run checkpatch prior to sending patches Cc: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
…checkpatch-fixes WARNING: please, no space before tabs torvalds#506: FILE: mm/gup.c:1513: +^I * ^I the page dirty with FOLL_WRITE -- which doesn't make a$ WARNING: please, no space before tabs torvalds#507: FILE: mm/gup.c:1514: +^I * ^I difference with !FOLL_FORCE, because the page is writable$ WARNING: please, no space before tabs torvalds#508: FILE: mm/gup.c:1515: +^I * ^I in the page table.$ total: 0 errors, 3 warnings, 214 lines checked NOTE: For some of the reported defects, checkpatch may be able to mechanically convert to the typical style using --fix or --fix-inplace. ./patches/mm-madvise-introduce-madv_populate_readwrite-to-prefault-page-tables.patch has style problems, please review. NOTE: If any of the errors are false positives, please report them to the maintainer, see CHECKPATCH in MAINTAINERS. Please run checkpatch prior to sending patches Cc: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
…checkpatch-fixes WARNING: please, no space before tabs torvalds#506: FILE: mm/gup.c:1513: +^I * ^I the page dirty with FOLL_WRITE -- which doesn't make a$ WARNING: please, no space before tabs torvalds#507: FILE: mm/gup.c:1514: +^I * ^I difference with !FOLL_FORCE, because the page is writable$ WARNING: please, no space before tabs torvalds#508: FILE: mm/gup.c:1515: +^I * ^I in the page table.$ total: 0 errors, 3 warnings, 214 lines checked NOTE: For some of the reported defects, checkpatch may be able to mechanically convert to the typical style using --fix or --fix-inplace. ./patches/mm-madvise-introduce-madv_populate_readwrite-to-prefault-page-tables.patch has style problems, please review. NOTE: If any of the errors are false positives, please report them to the maintainer, see CHECKPATCH in MAINTAINERS. Please run checkpatch prior to sending patches Cc: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
…checkpatch-fixes WARNING: please, no space before tabs torvalds#506: FILE: mm/gup.c:1513: +^I * ^I the page dirty with FOLL_WRITE -- which doesn't make a$ WARNING: please, no space before tabs torvalds#507: FILE: mm/gup.c:1514: +^I * ^I difference with !FOLL_FORCE, because the page is writable$ WARNING: please, no space before tabs torvalds#508: FILE: mm/gup.c:1515: +^I * ^I in the page table.$ total: 0 errors, 3 warnings, 214 lines checked NOTE: For some of the reported defects, checkpatch may be able to mechanically convert to the typical style using --fix or --fix-inplace. ./patches/mm-madvise-introduce-madv_populate_readwrite-to-prefault-page-tables.patch has style problems, please review. NOTE: If any of the errors are false positives, please report them to the maintainer, see CHECKPATCH in MAINTAINERS. Please run checkpatch prior to sending patches Cc: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
…checkpatch-fixes WARNING: please, no space before tabs torvalds#506: FILE: mm/gup.c:1513: +^I * ^I the page dirty with FOLL_WRITE -- which doesn't make a$ WARNING: please, no space before tabs torvalds#507: FILE: mm/gup.c:1514: +^I * ^I difference with !FOLL_FORCE, because the page is writable$ WARNING: please, no space before tabs torvalds#508: FILE: mm/gup.c:1515: +^I * ^I in the page table.$ total: 0 errors, 3 warnings, 214 lines checked NOTE: For some of the reported defects, checkpatch may be able to mechanically convert to the typical style using --fix or --fix-inplace. ./patches/mm-madvise-introduce-madv_populate_readwrite-to-prefault-page-tables.patch has style problems, please review. NOTE: If any of the errors are false positives, please report them to the maintainer, see CHECKPATCH in MAINTAINERS. Please run checkpatch prior to sending patches Cc: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
…checkpatch-fixes WARNING: please, no space before tabs torvalds#506: FILE: mm/gup.c:1513: +^I * ^I the page dirty with FOLL_WRITE -- which doesn't make a$ WARNING: please, no space before tabs torvalds#507: FILE: mm/gup.c:1514: +^I * ^I difference with !FOLL_FORCE, because the page is writable$ WARNING: please, no space before tabs torvalds#508: FILE: mm/gup.c:1515: +^I * ^I in the page table.$ total: 0 errors, 3 warnings, 214 lines checked NOTE: For some of the reported defects, checkpatch may be able to mechanically convert to the typical style using --fix or --fix-inplace. ./patches/mm-madvise-introduce-madv_populate_readwrite-to-prefault-page-tables.patch has style problems, please review. NOTE: If any of the errors are false positives, please report them to the maintainer, see CHECKPATCH in MAINTAINERS. Please run checkpatch prior to sending patches Cc: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
…checkpatch-fixes WARNING: please, no space before tabs torvalds#506: FILE: mm/gup.c:1513: +^I * ^I the page dirty with FOLL_WRITE -- which doesn't make a$ WARNING: please, no space before tabs torvalds#507: FILE: mm/gup.c:1514: +^I * ^I difference with !FOLL_FORCE, because the page is writable$ WARNING: please, no space before tabs torvalds#508: FILE: mm/gup.c:1515: +^I * ^I in the page table.$ total: 0 errors, 3 warnings, 214 lines checked NOTE: For some of the reported defects, checkpatch may be able to mechanically convert to the typical style using --fix or --fix-inplace. ./patches/mm-madvise-introduce-madv_populate_readwrite-to-prefault-page-tables.patch has style problems, please review. NOTE: If any of the errors are false positives, please report them to the maintainer, see CHECKPATCH in MAINTAINERS. Please run checkpatch prior to sending patches Cc: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
…ntries Jiri Olsa reported a fault when running: # cat /proc/kallsyms | grep ksys_read ffffffff8136d580 T ksys_read # objdump -d --start-address=0xffffffff8136d580 --stop-address=0xffffffff8136d590 /proc/kcore /proc/kcore: file format elf64-x86-64 Segmentation fault general protection fault, probably for non-canonical address 0xf887ffcbff000: 0000 [#1] SMP PTI CPU: 12 PID: 1079 Comm: objdump Not tainted 5.14.0-rc5qemu+ torvalds#508 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-4.fc34 04/01/2014 RIP: 0010:kern_addr_valid Call Trace: read_kcore ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? trace_hardirqs_on ? rcu_read_lock_sched_held ? lock_acquire ? lock_acquire ? rcu_read_lock_sched_held ? lock_acquire ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? lock_release ? _raw_spin_unlock ? __handle_mm_fault ? rcu_read_lock_sched_held ? lock_acquire ? rcu_read_lock_sched_held ? lock_release proc_reg_read ? vfs_read vfs_read ksys_read do_syscall_64 entry_SYSCALL_64_after_hwframe The fault happens because kern_addr_valid() dereferences existent but not present PMD in the high kernel mappings. Such PMDs are created when free_kernel_image_pages() frees regions larger than 2Mb. In this case, a part of the freed memory is mapped with PMDs and the set_memory_np_noalias() -> ... -> __change_page_attr() sequence will mark the PMD as not present rather than wipe it completely. Have kern_addr_valid() check whether higher level page table entries are present before trying to dereference them to fix this issue and to avoid similar issues in the future. Stable backporting note: ------------------------ Note that the stable marking is for all active stable branches because there could be cases where pagetable entries exist but are not valid - see 9a14aef ("x86: cpa, fix lookup_address"), for example. So make sure to be on the safe side here and use pXY_present() accessors rather than pXY_none() which could #GP when accessing pages in the direct map. Also see: c40a56a ("x86/mm/init: Remove freed kernel image areas from alias mapping") for more info. Reported-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: David Hildenbrand <david@redhat.com> Acked-by: Dave Hansen <dave.hansen@intel.com> Tested-by: Jiri Olsa <jolsa@redhat.com> Cc: <stable@vger.kernel.org> # 4.4+ Link: https://lkml.kernel.org/r/20210819132717.19358-1-rppt@kernel.org
…ntries commit 34b1999 upstream. Jiri Olsa reported a fault when running: # cat /proc/kallsyms | grep ksys_read ffffffff8136d580 T ksys_read # objdump -d --start-address=0xffffffff8136d580 --stop-address=0xffffffff8136d590 /proc/kcore /proc/kcore: file format elf64-x86-64 Segmentation fault general protection fault, probably for non-canonical address 0xf887ffcbff000: 0000 [#1] SMP PTI CPU: 12 PID: 1079 Comm: objdump Not tainted 5.14.0-rc5qemu+ torvalds#508 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-4.fc34 04/01/2014 RIP: 0010:kern_addr_valid Call Trace: read_kcore ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? trace_hardirqs_on ? rcu_read_lock_sched_held ? lock_acquire ? lock_acquire ? rcu_read_lock_sched_held ? lock_acquire ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? lock_release ? _raw_spin_unlock ? __handle_mm_fault ? rcu_read_lock_sched_held ? lock_acquire ? rcu_read_lock_sched_held ? lock_release proc_reg_read ? vfs_read vfs_read ksys_read do_syscall_64 entry_SYSCALL_64_after_hwframe The fault happens because kern_addr_valid() dereferences existent but not present PMD in the high kernel mappings. Such PMDs are created when free_kernel_image_pages() frees regions larger than 2Mb. In this case, a part of the freed memory is mapped with PMDs and the set_memory_np_noalias() -> ... -> __change_page_attr() sequence will mark the PMD as not present rather than wipe it completely. Have kern_addr_valid() check whether higher level page table entries are present before trying to dereference them to fix this issue and to avoid similar issues in the future. Stable backporting note: ------------------------ Note that the stable marking is for all active stable branches because there could be cases where pagetable entries exist but are not valid - see 9a14aef ("x86: cpa, fix lookup_address"), for example. So make sure to be on the safe side here and use pXY_present() accessors rather than pXY_none() which could #GP when accessing pages in the direct map. Also see: c40a56a ("x86/mm/init: Remove freed kernel image areas from alias mapping") for more info. Reported-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: David Hildenbrand <david@redhat.com> Acked-by: Dave Hansen <dave.hansen@intel.com> Tested-by: Jiri Olsa <jolsa@redhat.com> Cc: <stable@vger.kernel.org> # 4.4+ Link: https://lkml.kernel.org/r/20210819132717.19358-1-rppt@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
…ntries commit 34b1999 upstream. Jiri Olsa reported a fault when running: # cat /proc/kallsyms | grep ksys_read ffffffff8136d580 T ksys_read # objdump -d --start-address=0xffffffff8136d580 --stop-address=0xffffffff8136d590 /proc/kcore /proc/kcore: file format elf64-x86-64 Segmentation fault general protection fault, probably for non-canonical address 0xf887ffcbff000: 0000 [Freescale#1] SMP PTI CPU: 12 PID: 1079 Comm: objdump Not tainted 5.14.0-rc5qemu+ Freescale#508 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-4.fc34 04/01/2014 RIP: 0010:kern_addr_valid Call Trace: read_kcore ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? trace_hardirqs_on ? rcu_read_lock_sched_held ? lock_acquire ? lock_acquire ? rcu_read_lock_sched_held ? lock_acquire ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? lock_release ? _raw_spin_unlock ? __handle_mm_fault ? rcu_read_lock_sched_held ? lock_acquire ? rcu_read_lock_sched_held ? lock_release proc_reg_read ? vfs_read vfs_read ksys_read do_syscall_64 entry_SYSCALL_64_after_hwframe The fault happens because kern_addr_valid() dereferences existent but not present PMD in the high kernel mappings. Such PMDs are created when free_kernel_image_pages() frees regions larger than 2Mb. In this case, a part of the freed memory is mapped with PMDs and the set_memory_np_noalias() -> ... -> __change_page_attr() sequence will mark the PMD as not present rather than wipe it completely. Have kern_addr_valid() check whether higher level page table entries are present before trying to dereference them to fix this issue and to avoid similar issues in the future. Stable backporting note: ------------------------ Note that the stable marking is for all active stable branches because there could be cases where pagetable entries exist but are not valid - see 9a14aef ("x86: cpa, fix lookup_address"), for example. So make sure to be on the safe side here and use pXY_present() accessors rather than pXY_none() which could #GP when accessing pages in the direct map. Also see: c40a56a ("x86/mm/init: Remove freed kernel image areas from alias mapping") for more info. Reported-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: David Hildenbrand <david@redhat.com> Acked-by: Dave Hansen <dave.hansen@intel.com> Tested-by: Jiri Olsa <jolsa@redhat.com> Cc: <stable@vger.kernel.org> # 4.4+ Link: https://lkml.kernel.org/r/20210819132717.19358-1-rppt@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
…ntries commit 34b1999 upstream. Jiri Olsa reported a fault when running: # cat /proc/kallsyms | grep ksys_read ffffffff8136d580 T ksys_read # objdump -d --start-address=0xffffffff8136d580 --stop-address=0xffffffff8136d590 /proc/kcore /proc/kcore: file format elf64-x86-64 Segmentation fault general protection fault, probably for non-canonical address 0xf887ffcbff000: 0000 [Freescale#1] SMP PTI CPU: 12 PID: 1079 Comm: objdump Not tainted 5.14.0-rc5qemu+ Freescale#508 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-4.fc34 04/01/2014 RIP: 0010:kern_addr_valid Call Trace: read_kcore ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? trace_hardirqs_on ? rcu_read_lock_sched_held ? lock_acquire ? lock_acquire ? rcu_read_lock_sched_held ? lock_acquire ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? lock_release ? _raw_spin_unlock ? __handle_mm_fault ? rcu_read_lock_sched_held ? lock_acquire ? rcu_read_lock_sched_held ? lock_release proc_reg_read ? vfs_read vfs_read ksys_read do_syscall_64 entry_SYSCALL_64_after_hwframe The fault happens because kern_addr_valid() dereferences existent but not present PMD in the high kernel mappings. Such PMDs are created when free_kernel_image_pages() frees regions larger than 2Mb. In this case, a part of the freed memory is mapped with PMDs and the set_memory_np_noalias() -> ... -> __change_page_attr() sequence will mark the PMD as not present rather than wipe it completely. Have kern_addr_valid() check whether higher level page table entries are present before trying to dereference them to fix this issue and to avoid similar issues in the future. Stable backporting note: ------------------------ Note that the stable marking is for all active stable branches because there could be cases where pagetable entries exist but are not valid - see 9a14aef ("x86: cpa, fix lookup_address"), for example. So make sure to be on the safe side here and use pXY_present() accessors rather than pXY_none() which could #GP when accessing pages in the direct map. Also see: c40a56a ("x86/mm/init: Remove freed kernel image areas from alias mapping") for more info. Reported-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: David Hildenbrand <david@redhat.com> Acked-by: Dave Hansen <dave.hansen@intel.com> Tested-by: Jiri Olsa <jolsa@redhat.com> Cc: <stable@vger.kernel.org> # 4.4+ Link: https://lkml.kernel.org/r/20210819132717.19358-1-rppt@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
…ntries commit 34b1999 upstream. Jiri Olsa reported a fault when running: # cat /proc/kallsyms | grep ksys_read ffffffff8136d580 T ksys_read # objdump -d --start-address=0xffffffff8136d580 --stop-address=0xffffffff8136d590 /proc/kcore /proc/kcore: file format elf64-x86-64 Segmentation fault general protection fault, probably for non-canonical address 0xf887ffcbff000: 0000 [#1] SMP PTI CPU: 12 PID: 1079 Comm: objdump Not tainted 5.14.0-rc5qemu+ torvalds#508 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-4.fc34 04/01/2014 RIP: 0010:kern_addr_valid Call Trace: read_kcore ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? trace_hardirqs_on ? rcu_read_lock_sched_held ? lock_acquire ? lock_acquire ? rcu_read_lock_sched_held ? lock_acquire ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? lock_release ? _raw_spin_unlock ? __handle_mm_fault ? rcu_read_lock_sched_held ? lock_acquire ? rcu_read_lock_sched_held ? lock_release proc_reg_read ? vfs_read vfs_read ksys_read do_syscall_64 entry_SYSCALL_64_after_hwframe The fault happens because kern_addr_valid() dereferences existent but not present PMD in the high kernel mappings. Such PMDs are created when free_kernel_image_pages() frees regions larger than 2Mb. In this case, a part of the freed memory is mapped with PMDs and the set_memory_np_noalias() -> ... -> __change_page_attr() sequence will mark the PMD as not present rather than wipe it completely. Have kern_addr_valid() check whether higher level page table entries are present before trying to dereference them to fix this issue and to avoid similar issues in the future. Stable backporting note: ------------------------ Note that the stable marking is for all active stable branches because there could be cases where pagetable entries exist but are not valid - see 9a14aef ("x86: cpa, fix lookup_address"), for example. So make sure to be on the safe side here and use pXY_present() accessors rather than pXY_none() which could #GP when accessing pages in the direct map. Also see: c40a56a ("x86/mm/init: Remove freed kernel image areas from alias mapping") for more info. Reported-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: David Hildenbrand <david@redhat.com> Acked-by: Dave Hansen <dave.hansen@intel.com> Tested-by: Jiri Olsa <jolsa@redhat.com> Cc: <stable@vger.kernel.org> # 4.4+ Link: https://lkml.kernel.org/r/20210819132717.19358-1-rppt@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
…ntries commit 34b1999 upstream. Jiri Olsa reported a fault when running: # cat /proc/kallsyms | grep ksys_read ffffffff8136d580 T ksys_read # objdump -d --start-address=0xffffffff8136d580 --stop-address=0xffffffff8136d590 /proc/kcore /proc/kcore: file format elf64-x86-64 Segmentation fault general protection fault, probably for non-canonical address 0xf887ffcbff000: 0000 [#1] SMP PTI CPU: 12 PID: 1079 Comm: objdump Not tainted 5.14.0-rc5qemu+ torvalds#508 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-4.fc34 04/01/2014 RIP: 0010:kern_addr_valid Call Trace: read_kcore ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? trace_hardirqs_on ? rcu_read_lock_sched_held ? lock_acquire ? lock_acquire ? rcu_read_lock_sched_held ? lock_acquire ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? lock_release ? _raw_spin_unlock ? __handle_mm_fault ? rcu_read_lock_sched_held ? lock_acquire ? rcu_read_lock_sched_held ? lock_release proc_reg_read ? vfs_read vfs_read ksys_read do_syscall_64 entry_SYSCALL_64_after_hwframe The fault happens because kern_addr_valid() dereferences existent but not present PMD in the high kernel mappings. Such PMDs are created when free_kernel_image_pages() frees regions larger than 2Mb. In this case, a part of the freed memory is mapped with PMDs and the set_memory_np_noalias() -> ... -> __change_page_attr() sequence will mark the PMD as not present rather than wipe it completely. Have kern_addr_valid() check whether higher level page table entries are present before trying to dereference them to fix this issue and to avoid similar issues in the future. Stable backporting note: ------------------------ Note that the stable marking is for all active stable branches because there could be cases where pagetable entries exist but are not valid - see 9a14aef ("x86: cpa, fix lookup_address"), for example. So make sure to be on the safe side here and use pXY_present() accessors rather than pXY_none() which could #GP when accessing pages in the direct map. Also see: c40a56a ("x86/mm/init: Remove freed kernel image areas from alias mapping") for more info. Reported-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: David Hildenbrand <david@redhat.com> Acked-by: Dave Hansen <dave.hansen@intel.com> Tested-by: Jiri Olsa <jolsa@redhat.com> Cc: <stable@vger.kernel.org> # 4.4+ Link: https://lkml.kernel.org/r/20210819132717.19358-1-rppt@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
…ntries commit 34b1999 upstream. Jiri Olsa reported a fault when running: # cat /proc/kallsyms | grep ksys_read ffffffff8136d580 T ksys_read # objdump -d --start-address=0xffffffff8136d580 --stop-address=0xffffffff8136d590 /proc/kcore /proc/kcore: file format elf64-x86-64 Segmentation fault general protection fault, probably for non-canonical address 0xf887ffcbff000: 0000 [#1] SMP PTI CPU: 12 PID: 1079 Comm: objdump Not tainted 5.14.0-rc5qemu+ torvalds#508 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-4.fc34 04/01/2014 RIP: 0010:kern_addr_valid Call Trace: read_kcore ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? trace_hardirqs_on ? rcu_read_lock_sched_held ? lock_acquire ? lock_acquire ? rcu_read_lock_sched_held ? lock_acquire ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? lock_release ? _raw_spin_unlock ? __handle_mm_fault ? rcu_read_lock_sched_held ? lock_acquire ? rcu_read_lock_sched_held ? lock_release proc_reg_read ? vfs_read vfs_read ksys_read do_syscall_64 entry_SYSCALL_64_after_hwframe The fault happens because kern_addr_valid() dereferences existent but not present PMD in the high kernel mappings. Such PMDs are created when free_kernel_image_pages() frees regions larger than 2Mb. In this case, a part of the freed memory is mapped with PMDs and the set_memory_np_noalias() -> ... -> __change_page_attr() sequence will mark the PMD as not present rather than wipe it completely. Have kern_addr_valid() check whether higher level page table entries are present before trying to dereference them to fix this issue and to avoid similar issues in the future. Stable backporting note: ------------------------ Note that the stable marking is for all active stable branches because there could be cases where pagetable entries exist but are not valid - see 9a14aef ("x86: cpa, fix lookup_address"), for example. So make sure to be on the safe side here and use pXY_present() accessors rather than pXY_none() which could #GP when accessing pages in the direct map. Also see: c40a56a ("x86/mm/init: Remove freed kernel image areas from alias mapping") for more info. Reported-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: David Hildenbrand <david@redhat.com> Acked-by: Dave Hansen <dave.hansen@intel.com> Tested-by: Jiri Olsa <jolsa@redhat.com> Cc: <stable@vger.kernel.org> # 4.4+ Link: https://lkml.kernel.org/r/20210819132717.19358-1-rppt@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
…ntries commit 34b1999 upstream. Jiri Olsa reported a fault when running: # cat /proc/kallsyms | grep ksys_read ffffffff8136d580 T ksys_read # objdump -d --start-address=0xffffffff8136d580 --stop-address=0xffffffff8136d590 /proc/kcore /proc/kcore: file format elf64-x86-64 Segmentation fault general protection fault, probably for non-canonical address 0xf887ffcbff000: 0000 [#1] SMP PTI CPU: 12 PID: 1079 Comm: objdump Not tainted 5.14.0-rc5qemu+ torvalds#508 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-4.fc34 04/01/2014 RIP: 0010:kern_addr_valid Call Trace: read_kcore ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? trace_hardirqs_on ? rcu_read_lock_sched_held ? lock_acquire ? lock_acquire ? rcu_read_lock_sched_held ? lock_acquire ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? lock_release ? _raw_spin_unlock ? __handle_mm_fault ? rcu_read_lock_sched_held ? lock_acquire ? rcu_read_lock_sched_held ? lock_release proc_reg_read ? vfs_read vfs_read ksys_read do_syscall_64 entry_SYSCALL_64_after_hwframe The fault happens because kern_addr_valid() dereferences existent but not present PMD in the high kernel mappings. Such PMDs are created when free_kernel_image_pages() frees regions larger than 2Mb. In this case, a part of the freed memory is mapped with PMDs and the set_memory_np_noalias() -> ... -> __change_page_attr() sequence will mark the PMD as not present rather than wipe it completely. Have kern_addr_valid() check whether higher level page table entries are present before trying to dereference them to fix this issue and to avoid similar issues in the future. Stable backporting note: ------------------------ Note that the stable marking is for all active stable branches because there could be cases where pagetable entries exist but are not valid - see 9a14aef ("x86: cpa, fix lookup_address"), for example. So make sure to be on the safe side here and use pXY_present() accessors rather than pXY_none() which could #GP when accessing pages in the direct map. Also see: c40a56a ("x86/mm/init: Remove freed kernel image areas from alias mapping") for more info. Reported-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: David Hildenbrand <david@redhat.com> Acked-by: Dave Hansen <dave.hansen@intel.com> Tested-by: Jiri Olsa <jolsa@redhat.com> Cc: <stable@vger.kernel.org> # 4.4+ Link: https://lkml.kernel.org/r/20210819132717.19358-1-rppt@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
…ntries commit 34b1999 upstream. Jiri Olsa reported a fault when running: # cat /proc/kallsyms | grep ksys_read ffffffff8136d580 T ksys_read # objdump -d --start-address=0xffffffff8136d580 --stop-address=0xffffffff8136d590 /proc/kcore /proc/kcore: file format elf64-x86-64 Segmentation fault general protection fault, probably for non-canonical address 0xf887ffcbff000: 0000 [#1] SMP PTI CPU: 12 PID: 1079 Comm: objdump Not tainted 5.14.0-rc5qemu+ torvalds#508 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-4.fc34 04/01/2014 RIP: 0010:kern_addr_valid Call Trace: read_kcore ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? trace_hardirqs_on ? rcu_read_lock_sched_held ? lock_acquire ? lock_acquire ? rcu_read_lock_sched_held ? lock_acquire ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? lock_release ? _raw_spin_unlock ? __handle_mm_fault ? rcu_read_lock_sched_held ? lock_acquire ? rcu_read_lock_sched_held ? lock_release proc_reg_read ? vfs_read vfs_read ksys_read do_syscall_64 entry_SYSCALL_64_after_hwframe The fault happens because kern_addr_valid() dereferences existent but not present PMD in the high kernel mappings. Such PMDs are created when free_kernel_image_pages() frees regions larger than 2Mb. In this case, a part of the freed memory is mapped with PMDs and the set_memory_np_noalias() -> ... -> __change_page_attr() sequence will mark the PMD as not present rather than wipe it completely. Have kern_addr_valid() check whether higher level page table entries are present before trying to dereference them to fix this issue and to avoid similar issues in the future. Stable backporting note: ------------------------ Note that the stable marking is for all active stable branches because there could be cases where pagetable entries exist but are not valid - see 9a14aef ("x86: cpa, fix lookup_address"), for example. So make sure to be on the safe side here and use pXY_present() accessors rather than pXY_none() which could #GP when accessing pages in the direct map. Also see: c40a56a ("x86/mm/init: Remove freed kernel image areas from alias mapping") for more info. Reported-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: David Hildenbrand <david@redhat.com> Acked-by: Dave Hansen <dave.hansen@intel.com> Tested-by: Jiri Olsa <jolsa@redhat.com> Cc: <stable@vger.kernel.org> # 4.4+ Link: https://lkml.kernel.org/r/20210819132717.19358-1-rppt@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
…ntries commit 34b1999 upstream. Jiri Olsa reported a fault when running: # cat /proc/kallsyms | grep ksys_read ffffffff8136d580 T ksys_read # objdump -d --start-address=0xffffffff8136d580 --stop-address=0xffffffff8136d590 /proc/kcore /proc/kcore: file format elf64-x86-64 Segmentation fault general protection fault, probably for non-canonical address 0xf887ffcbff000: 0000 [#1] SMP PTI CPU: 12 PID: 1079 Comm: objdump Not tainted 5.14.0-rc5qemu+ torvalds#508 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-4.fc34 04/01/2014 RIP: 0010:kern_addr_valid Call Trace: read_kcore ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? trace_hardirqs_on ? rcu_read_lock_sched_held ? lock_acquire ? lock_acquire ? rcu_read_lock_sched_held ? lock_acquire ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? lock_release ? _raw_spin_unlock ? __handle_mm_fault ? rcu_read_lock_sched_held ? lock_acquire ? rcu_read_lock_sched_held ? lock_release proc_reg_read ? vfs_read vfs_read ksys_read do_syscall_64 entry_SYSCALL_64_after_hwframe The fault happens because kern_addr_valid() dereferences existent but not present PMD in the high kernel mappings. Such PMDs are created when free_kernel_image_pages() frees regions larger than 2Mb. In this case, a part of the freed memory is mapped with PMDs and the set_memory_np_noalias() -> ... -> __change_page_attr() sequence will mark the PMD as not present rather than wipe it completely. Have kern_addr_valid() check whether higher level page table entries are present before trying to dereference them to fix this issue and to avoid similar issues in the future. Stable backporting note: ------------------------ Note that the stable marking is for all active stable branches because there could be cases where pagetable entries exist but are not valid - see 9a14aef ("x86: cpa, fix lookup_address"), for example. So make sure to be on the safe side here and use pXY_present() accessors rather than pXY_none() which could #GP when accessing pages in the direct map. Also see: c40a56a ("x86/mm/init: Remove freed kernel image areas from alias mapping") for more info. Reported-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: David Hildenbrand <david@redhat.com> Acked-by: Dave Hansen <dave.hansen@intel.com> Tested-by: Jiri Olsa <jolsa@redhat.com> Cc: <stable@vger.kernel.org> # 4.4+ Link: https://lkml.kernel.org/r/20210819132717.19358-1-rppt@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
…ntries commit 34b1999 upstream. Jiri Olsa reported a fault when running: # cat /proc/kallsyms | grep ksys_read ffffffff8136d580 T ksys_read # objdump -d --start-address=0xffffffff8136d580 --stop-address=0xffffffff8136d590 /proc/kcore /proc/kcore: file format elf64-x86-64 Segmentation fault general protection fault, probably for non-canonical address 0xf887ffcbff000: 0000 [#1] SMP PTI CPU: 12 PID: 1079 Comm: objdump Not tainted 5.14.0-rc5qemu+ torvalds#508 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-4.fc34 04/01/2014 RIP: 0010:kern_addr_valid Call Trace: read_kcore ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? trace_hardirqs_on ? rcu_read_lock_sched_held ? lock_acquire ? lock_acquire ? rcu_read_lock_sched_held ? lock_acquire ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? lock_release ? _raw_spin_unlock ? __handle_mm_fault ? rcu_read_lock_sched_held ? lock_acquire ? rcu_read_lock_sched_held ? lock_release proc_reg_read ? vfs_read vfs_read ksys_read do_syscall_64 entry_SYSCALL_64_after_hwframe The fault happens because kern_addr_valid() dereferences existent but not present PMD in the high kernel mappings. Such PMDs are created when free_kernel_image_pages() frees regions larger than 2Mb. In this case, a part of the freed memory is mapped with PMDs and the set_memory_np_noalias() -> ... -> __change_page_attr() sequence will mark the PMD as not present rather than wipe it completely. Have kern_addr_valid() check whether higher level page table entries are present before trying to dereference them to fix this issue and to avoid similar issues in the future. Stable backporting note: ------------------------ Note that the stable marking is for all active stable branches because there could be cases where pagetable entries exist but are not valid - see 9a14aef ("x86: cpa, fix lookup_address"), for example. So make sure to be on the safe side here and use pXY_present() accessors rather than pXY_none() which could #GP when accessing pages in the direct map. Also see: c40a56a ("x86/mm/init: Remove freed kernel image areas from alias mapping") for more info. Reported-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: David Hildenbrand <david@redhat.com> Acked-by: Dave Hansen <dave.hansen@intel.com> Tested-by: Jiri Olsa <jolsa@redhat.com> Cc: <stable@vger.kernel.org> # 4.4+ Link: https://lkml.kernel.org/r/20210819132717.19358-1-rppt@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
…ntries commit 34b1999 upstream. Jiri Olsa reported a fault when running: # cat /proc/kallsyms | grep ksys_read ffffffff8136d580 T ksys_read # objdump -d --start-address=0xffffffff8136d580 --stop-address=0xffffffff8136d590 /proc/kcore /proc/kcore: file format elf64-x86-64 Segmentation fault general protection fault, probably for non-canonical address 0xf887ffcbff000: 0000 [#1] SMP PTI CPU: 12 PID: 1079 Comm: objdump Not tainted 5.14.0-rc5qemu+ torvalds#508 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-4.fc34 04/01/2014 RIP: 0010:kern_addr_valid Call Trace: read_kcore ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? trace_hardirqs_on ? rcu_read_lock_sched_held ? lock_acquire ? lock_acquire ? rcu_read_lock_sched_held ? lock_acquire ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? lock_release ? _raw_spin_unlock ? __handle_mm_fault ? rcu_read_lock_sched_held ? lock_acquire ? rcu_read_lock_sched_held ? lock_release proc_reg_read ? vfs_read vfs_read ksys_read do_syscall_64 entry_SYSCALL_64_after_hwframe The fault happens because kern_addr_valid() dereferences existent but not present PMD in the high kernel mappings. Such PMDs are created when free_kernel_image_pages() frees regions larger than 2Mb. In this case, a part of the freed memory is mapped with PMDs and the set_memory_np_noalias() -> ... -> __change_page_attr() sequence will mark the PMD as not present rather than wipe it completely. Have kern_addr_valid() check whether higher level page table entries are present before trying to dereference them to fix this issue and to avoid similar issues in the future. Stable backporting note: ------------------------ Note that the stable marking is for all active stable branches because there could be cases where pagetable entries exist but are not valid - see 9a14aef ("x86: cpa, fix lookup_address"), for example. So make sure to be on the safe side here and use pXY_present() accessors rather than pXY_none() which could #GP when accessing pages in the direct map. Also see: c40a56a ("x86/mm/init: Remove freed kernel image areas from alias mapping") for more info. Reported-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: David Hildenbrand <david@redhat.com> Acked-by: Dave Hansen <dave.hansen@intel.com> Tested-by: Jiri Olsa <jolsa@redhat.com> Cc: <stable@vger.kernel.org> # 4.4+ Link: https://lkml.kernel.org/r/20210819132717.19358-1-rppt@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
…ntries commit 34b1999 upstream. Jiri Olsa reported a fault when running: # cat /proc/kallsyms | grep ksys_read ffffffff8136d580 T ksys_read # objdump -d --start-address=0xffffffff8136d580 --stop-address=0xffffffff8136d590 /proc/kcore /proc/kcore: file format elf64-x86-64 Segmentation fault general protection fault, probably for non-canonical address 0xf887ffcbff000: 0000 [#1] SMP PTI CPU: 12 PID: 1079 Comm: objdump Not tainted 5.14.0-rc5qemu+ torvalds#508 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-4.fc34 04/01/2014 RIP: 0010:kern_addr_valid Call Trace: read_kcore ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? trace_hardirqs_on ? rcu_read_lock_sched_held ? lock_acquire ? lock_acquire ? rcu_read_lock_sched_held ? lock_acquire ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? lock_release ? _raw_spin_unlock ? __handle_mm_fault ? rcu_read_lock_sched_held ? lock_acquire ? rcu_read_lock_sched_held ? lock_release proc_reg_read ? vfs_read vfs_read ksys_read do_syscall_64 entry_SYSCALL_64_after_hwframe The fault happens because kern_addr_valid() dereferences existent but not present PMD in the high kernel mappings. Such PMDs are created when free_kernel_image_pages() frees regions larger than 2Mb. In this case, a part of the freed memory is mapped with PMDs and the set_memory_np_noalias() -> ... -> __change_page_attr() sequence will mark the PMD as not present rather than wipe it completely. Have kern_addr_valid() check whether higher level page table entries are present before trying to dereference them to fix this issue and to avoid similar issues in the future. Stable backporting note: ------------------------ Note that the stable marking is for all active stable branches because there could be cases where pagetable entries exist but are not valid - see 9a14aef ("x86: cpa, fix lookup_address"), for example. So make sure to be on the safe side here and use pXY_present() accessors rather than pXY_none() which could #GP when accessing pages in the direct map. Also see: c40a56a ("x86/mm/init: Remove freed kernel image areas from alias mapping") for more info. Reported-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: David Hildenbrand <david@redhat.com> Acked-by: Dave Hansen <dave.hansen@intel.com> Tested-by: Jiri Olsa <jolsa@redhat.com> Cc: <stable@vger.kernel.org> # 4.4+ Link: https://lkml.kernel.org/r/20210819132717.19358-1-rppt@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
rust: macros: module: remove unnecessary `.clone()`
…ntries Jiri Olsa reported a fault when running: # cat /proc/kallsyms | grep ksys_read ffffffff8136d580 T ksys_read # objdump -d --start-address=0xffffffff8136d580 --stop-address=0xffffffff8136d590 /proc/kcore /proc/kcore: file format elf64-x86-64 Segmentation fault general protection fault, probably for non-canonical address 0xf887ffcbff000: 0000 [#1] SMP PTI CPU: 12 PID: 1079 Comm: objdump Not tainted 5.14.0-rc5qemu+ torvalds#508 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-4.fc34 04/01/2014 RIP: 0010:kern_addr_valid Call Trace: read_kcore ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? trace_hardirqs_on ? rcu_read_lock_sched_held ? lock_acquire ? lock_acquire ? rcu_read_lock_sched_held ? lock_acquire ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? lock_release ? _raw_spin_unlock ? __handle_mm_fault ? rcu_read_lock_sched_held ? lock_acquire ? rcu_read_lock_sched_held ? lock_release proc_reg_read ? vfs_read vfs_read ksys_read do_syscall_64 entry_SYSCALL_64_after_hwframe The fault happens because kern_addr_valid() dereferences existent but not present PMD in the high kernel mappings. Such PMDs are created when free_kernel_image_pages() frees regions larger than 2Mb. In this case, a part of the freed memory is mapped with PMDs and the set_memory_np_noalias() -> ... -> __change_page_attr() sequence will mark the PMD as not present rather than wipe it completely. Have kern_addr_valid() check whether higher level page table entries are present before trying to dereference them to fix this issue and to avoid similar issues in the future. Stable backporting note: ------------------------ Note that the stable marking is for all active stable branches because there could be cases where pagetable entries exist but are not valid - see 9a14aef ("x86: cpa, fix lookup_address"), for example. So make sure to be on the safe side here and use pXY_present() accessors rather than pXY_none() which could #GP when accessing pages in the direct map. Also see: c40a56a ("x86/mm/init: Remove freed kernel image areas from alias mapping") for more info. Reported-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: David Hildenbrand <david@redhat.com> Acked-by: Dave Hansen <dave.hansen@intel.com> Tested-by: Jiri Olsa <jolsa@redhat.com> Cc: <stable@vger.kernel.org> # 4.4+ Link: https://lkml.kernel.org/r/20210819132717.19358-1-rppt@kernel.org
USB URB completion handlers run in interrupt context, so the URB resubmission must use GFP_ATOMIC. This fixes the following WARN()/BUG() log messages: [ 28.493744] BUG: sleeping function called from invalid context at include/linux/sched/mm.h:274 [ 28.493746] in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 0, name: swapper/9 [ 28.493748] preempt_count: 101, expected: 0 [ 28.493749] RCU nest depth: 0, expected: 0 [ 28.493750] INFO: lockdep is turned off. [ 28.493750] Preemption disabled at: [ 28.493751] [<ffffffff983b1736>] ___slab_alloc+0x8d6/0xea0 [ 28.493754] CPU: 9 PID: 0 Comm: swapper/9 Tainted: G O 6.0.0+ torvalds#508 [ 28.493755] Hardware name: LENOVO 21CEZ9Q3US/21CEZ9Q3US, BIOS N3AET66W (1.31 ) 09/09/2022 [ 28.493756] Call Trace: [ 28.493757] <IRQ> [ 28.493758] dump_stack_lvl+0x5b/0x77 [ 28.493761] __might_resched.cold+0xff/0x13a [ 28.493763] __kmalloc+0x209/0x3d0 [ 28.493765] xhci_urb_enqueue+0xee/0x5a0 [ 28.493768] usb_hcd_submit_urb+0xbd/0xb80 [ 28.493770] ? _raw_spin_unlock_irqrestore+0x30/0x60 [ 28.493772] ? _raw_spin_unlock_irqrestore+0x30/0x60 [ 28.493773] ? lockdep_hardirqs_on+0x7d/0x100 [ 28.493776] ? _raw_spin_unlock_irqrestore+0x40/0x60 [ 28.493777] ? __wake_up_common_lock+0x77/0x90 [ 28.493780] ljca_read_complete+0x12c/0x28b [ljca] Signed-off-by: Hans de Goede <hdegoede@redhat.com>
USB URB completion handlers run in interrupt context, so the URB resubmission must use GFP_ATOMIC. This fixes the following WARN()/BUG() log messages: [ 28.493744] BUG: sleeping function called from invalid context at include/linux/sched/mm.h:274 [ 28.493746] in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 0, name: swapper/9 [ 28.493748] preempt_count: 101, expected: 0 [ 28.493749] RCU nest depth: 0, expected: 0 [ 28.493750] INFO: lockdep is turned off. [ 28.493750] Preemption disabled at: [ 28.493751] [<ffffffff983b1736>] ___slab_alloc+0x8d6/0xea0 [ 28.493754] CPU: 9 PID: 0 Comm: swapper/9 Tainted: G O 6.0.0+ torvalds#508 [ 28.493755] Hardware name: LENOVO 21CEZ9Q3US/21CEZ9Q3US, BIOS N3AET66W (1.31 ) 09/09/2022 [ 28.493756] Call Trace: [ 28.493757] <IRQ> [ 28.493758] dump_stack_lvl+0x5b/0x77 [ 28.493761] __might_resched.cold+0xff/0x13a [ 28.493763] __kmalloc+0x209/0x3d0 [ 28.493765] xhci_urb_enqueue+0xee/0x5a0 [ 28.493768] usb_hcd_submit_urb+0xbd/0xb80 [ 28.493770] ? _raw_spin_unlock_irqrestore+0x30/0x60 [ 28.493772] ? _raw_spin_unlock_irqrestore+0x30/0x60 [ 28.493773] ? lockdep_hardirqs_on+0x7d/0x100 [ 28.493776] ? _raw_spin_unlock_irqrestore+0x40/0x60 [ 28.493777] ? __wake_up_common_lock+0x77/0x90 [ 28.493780] ljca_read_complete+0x12c/0x28b [ljca] Signed-off-by: Hans de Goede <hdegoede@redhat.com>
[docs] - linux/documentation/abi/readme - minor tweaks [writing]