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authorMitsuo Hayasaka <mitsuo.hayasaka.hu@hitachi.com>2011-11-29 15:08:29 +0900
committerIngo Molnar <mingo@elte.hu>2011-12-05 11:37:45 +0100
commit37fe6a42b3433b79a159ceb06a94cd1ef00e279d (patch)
tree4852070d6782545e41b0fbd7f80e1d1414917c6b /arch/x86/kernel/irq_64.c
parentx86: Add user_mode_vm check in stack_overflow_check (diff)
downloadlinux-dev-37fe6a42b3433b79a159ceb06a94cd1ef00e279d.tar.xz
linux-dev-37fe6a42b3433b79a159ceb06a94cd1ef00e279d.zip
x86: Check stack overflow in detail
Currently, only kernel stack is checked for the overflow, which is not sufficient for systems that need a high reliability. To enhance it, it is required to check the IRQ and exception stacks, as well. This patch checks all the stack types and will cause messages of stacks in detail when free stack space drops below a certain limit except user stack. Signed-off-by: Mitsuo Hayasaka <mitsuo.hayasaka.hu@hitachi.com> Cc: yrl.pp-manager.tt@hitachi.com Cc: Randy Dunlap <rdunlap@xenotime.net> Link: http://lkml.kernel.org/r/20111129060829.11076.51733.stgit@ltc219.sdl.hitachi.co.jp Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: "H. Peter Anvin" <hpa@zytor.com>
Diffstat (limited to 'arch/x86/kernel/irq_64.c')
-rw-r--r--arch/x86/kernel/irq_64.c29
1 files changed, 23 insertions, 6 deletions
diff --git a/arch/x86/kernel/irq_64.c b/arch/x86/kernel/irq_64.c
index 69bca468c47a..928a7e909619 100644
--- a/arch/x86/kernel/irq_64.c
+++ b/arch/x86/kernel/irq_64.c
@@ -36,18 +36,35 @@ EXPORT_PER_CPU_SYMBOL(irq_regs);
static inline void stack_overflow_check(struct pt_regs *regs)
{
#ifdef CONFIG_DEBUG_STACKOVERFLOW
+ struct orig_ist *oist;
+ u64 irq_stack_top, irq_stack_bottom;
+ u64 estack_top, estack_bottom;
u64 curbase = (u64)task_stack_page(current);
if (user_mode_vm(regs))
return;
- WARN_ONCE(regs->sp >= curbase &&
- regs->sp <= curbase + THREAD_SIZE &&
- regs->sp < curbase + sizeof(struct thread_info) +
- sizeof(struct pt_regs) + 128,
+ if (regs->sp >= curbase &&
+ regs->sp <= curbase + THREAD_SIZE &&
+ regs->sp >= curbase + sizeof(struct thread_info) +
+ sizeof(struct pt_regs) + 128)
+ return;
+
+ irq_stack_top = (u64)__get_cpu_var(irq_stack_union.irq_stack);
+ irq_stack_bottom = (u64)__get_cpu_var(irq_stack_ptr);
+ if (regs->sp >= irq_stack_top && regs->sp <= irq_stack_bottom)
+ return;
+
+ oist = &__get_cpu_var(orig_ist);
+ estack_top = (u64)oist->ist[0] - EXCEPTION_STKSZ;
+ estack_bottom = (u64)oist->ist[N_EXCEPTION_STACKS - 1];
+ if (regs->sp >= estack_top && regs->sp <= estack_bottom)
+ return;
- "do_IRQ: %s near stack overflow (cur:%Lx,sp:%lx)\n",
- current->comm, curbase, regs->sp);
+ WARN_ONCE(1, "do_IRQ(): %s has overflown the kernel stack (cur:%Lx,sp:%lx,irq stk top-bottom:%Lx-%Lx,exception stk top-bottom:%Lx-%Lx)\n",
+ current->comm, curbase, regs->sp,
+ irq_stack_top, irq_stack_bottom,
+ estack_top, estack_bottom);
#endif
}