linux/tools/testing
Dmitry Safonov 2a4d0c627f x86/selftests: Add clobbers for int80 on x86_64
Kernel erases R8..R11 registers prior returning to userspace
from int80:

  https://lkml.org/lkml/2009/10/1/164

GCC can reuse these registers and doesn't expect them to change
during syscall invocation. I met this kind of bug in CRIU once
GCC 6.1 and CLANG stored local variables in those registers
and the kernel zerofied them during syscall:

  990d33f1a1

By that reason I suggest to add those registers to clobbers
in selftests.  Also, as noted by Andy - removed unneeded clobber
for flags in INT $0x80 inline asm.

Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com>
Acked-by: Andy Lutomirski <luto@kernel.org>
Cc: 0x7f454c46@gmail.com
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kselftest@vger.kernel.org
Link: http://lkml.kernel.org/r/20170213101336.20486-1-dsafonov@virtuozzo.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-01 10:24:56 +01:00
..
fault-injection fault-injection: fix failcmd.sh warning 2012-07-31 18:42:38 -07:00
ktest These are various fixes that I have made and never got around to pushing. 2017-02-27 23:07:59 -08:00
nvdimm Merge branch 'for-4.10/libnvdimm' into libnvdimm-for-next 2016-12-17 15:08:10 -08:00
radix-tree radix tree test suite: Add config option for map shift 2017-02-13 21:44:10 -05:00
selftests x86/selftests: Add clobbers for int80 on x86_64 2017-03-01 10:24:56 +01:00