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| author | Josh Poimboeuf <jpoimboe@redhat.com> | 2016-10-26 10:41:50 -0500 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2016-10-27 08:32:38 +0200 |
| commit | 0d2b8579add41e08aa1110da864f1071d58e6048 (patch) | |
| tree | ee5e8f17b59d1cf6503159250724794f16267ceb | |
| parent | c32c47c68a0ae701088c5b2c3798856ed16746ae (diff) | |
| download | linux-0d2b8579add41e08aa1110da864f1071d58e6048.tar.gz linux-0d2b8579add41e08aa1110da864f1071d58e6048.tar.bz2 linux-0d2b8579add41e08aa1110da864f1071d58e6048.zip | |
x86/dumpstack: Warn on stack recursion
Print a warning if stack recursion is detected.
Use printk_deferred_once() because the unwinder can be called with the
console lock by lockdep via save_stack_trace().
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/def18247aafaab480844484398e793f552b79bda.1477496147.git.jpoimboe@redhat.com
[ Unbroke the lines. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
| -rw-r--r-- | arch/x86/kernel/dumpstack_32.c | 4 | ||||
| -rw-r--r-- | arch/x86/kernel/dumpstack_64.c | 4 |
2 files changed, 6 insertions, 2 deletions
diff --git a/arch/x86/kernel/dumpstack_32.c b/arch/x86/kernel/dumpstack_32.c index 90cf460d50bd..d7d20999d68c 100644 --- a/arch/x86/kernel/dumpstack_32.c +++ b/arch/x86/kernel/dumpstack_32.c @@ -109,8 +109,10 @@ recursion_check: * just break out and report an unknown stack type. */ if (visit_mask) { - if (*visit_mask & (1UL << info->type)) + if (*visit_mask & (1UL << info->type)) { + printk_deferred_once(KERN_WARNING "WARNING: stack recursion on stack type %d\n", info->type); goto unknown; + } *visit_mask |= 1UL << info->type; } diff --git a/arch/x86/kernel/dumpstack_64.c b/arch/x86/kernel/dumpstack_64.c index 310abf4542dc..ab0f8b90b51b 100644 --- a/arch/x86/kernel/dumpstack_64.c +++ b/arch/x86/kernel/dumpstack_64.c @@ -128,8 +128,10 @@ recursion_check: * just break out and report an unknown stack type. */ if (visit_mask) { - if (*visit_mask & (1UL << info->type)) + if (*visit_mask & (1UL << info->type)) { + printk_deferred_once(KERN_WARNING "WARNING: stack recursion on stack type %d\n", info->type); goto unknown; + } *visit_mask |= 1UL << info->type; } |