diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c index b68898ac07e19..392404688cec3 100644 --- a/arch/powerpc/kernel/process.c +++ b/arch/powerpc/kernel/process.c @@ -2258,6 +2258,22 @@ unsigned long __get_wchan(struct task_struct *p) return ret; } +static bool empty_user_regs(struct pt_regs *regs, struct task_struct *tsk) +{ + unsigned long stack_page; + + // A non-empty pt_regs should never have a zero MSR or TRAP value. + if (regs->msr || regs->trap) + return false; + + // Check it sits at the very base of the stack + stack_page = (unsigned long)task_stack_page(tsk); + if ((unsigned long)(regs + 1) != stack_page + THREAD_SIZE) + return false; + + return true; +} + static int kstack_depth_to_print = CONFIG_PRINT_STACK_DEPTH; void __no_sanitize_address show_stack(struct task_struct *tsk, @@ -2322,9 +2338,13 @@ void __no_sanitize_address show_stack(struct task_struct *tsk, lr = regs->link; printk("%s--- interrupt: %lx at %pS\n", loglvl, regs->trap, (void *)regs->nip); - __show_regs(regs); - printk("%s--- interrupt: %lx\n", - loglvl, regs->trap); + + // Detect the case of an empty pt_regs at the very base + // of the stack and suppress showing it in full. + if (!empty_user_regs(regs, tsk)) { + __show_regs(regs); + printk("%s--- interrupt: %lx\n", loglvl, regs->trap); + } firstframe = 1; }