x86/dumpstack: When OOPSing, rewind the stack before do_exit()
authorAndy Lutomirski <luto@kernel.org>
Thu, 14 Jul 2016 20:22:55 +0000 (13:22 -0700)
committerIngo Molnar <mingo@kernel.org>
Fri, 15 Jul 2016 08:26:28 +0000 (10:26 +0200)
commit2deb4be28077638591fe5fc593b7f8aabc140f42
tree3c06fe6e99676de863c22112927b70c6fd99acc4
parent46aea3873401836abb7f01200e7946e7d518b359
x86/dumpstack: When OOPSing, rewind the stack before do_exit()

If we call do_exit() with a clean stack, we greatly reduce the risk of
recursive oopses due to stack overflow in do_exit, and we allow
do_exit to work even if we OOPS from an IST stack.  The latter gives
us a much better chance of surviving long enough after we detect a
stack overflow to write out our logs.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
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/32f73ceb372ec61889598da5e5b145889b9f2e19.1468527351.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
arch/x86/entry/entry_32.S
arch/x86/entry/entry_64.S
arch/x86/kernel/dumpstack.c