linux/arch/x86
Steven Rostedt a38449ef59 x86: Specify a size for the cmp in the NMI handler
Linus noticed that the cmp used to check if the code segment is
__KERNEL_CS or not did not specify a size. Perhaps it does not matter
as H. Peter Anvin noted that user space can not set the bottom two
bits of the %cs register. But it's best not to let the assembly choose
and change things between different versions of gas, but instead just
pick the size.

Four bytes are used to compare the saved code segment against
__KERNEL_CS. Perhaps this might mess up Xen, but we can fix that when
the time comes.

Also I noticed that there was another non-specified cmp that checks
the special stack variable if it is 1 or 0. This too probably doesn't
matter what cmp is used, but this patch uses cmpl just to make it non
ambiguous.

Link: http://lkml.kernel.org/r/CA+55aFxfAn9MWRgS3O5k2tqN5ys1XrhSFVO5_9ZAoZKDVgNfGA@mail.gmail.com

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-02-20 19:45:26 -05:00
..
boot x86/boot-image: Don't leak phdrs in arch/x86/boot/compressed/misc.c::Parse_elf() 2012-01-26 11:30:29 +01:00
configs
crypto crypto: serpent-sse2 - remove unneeded LRW/XTS #ifdefs 2011-12-20 15:20:08 +08:00
ia32 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit 2012-01-17 16:41:31 -08:00
include/asm x86: Properly parenthesize cmpxchg() macro arguments 2012-01-26 21:18:29 +01:00
kernel x86: Specify a size for the cmp in the NMI handler 2012-02-20 19:45:26 -05:00
kvm module_param: make bool parameters really bool (arch) 2012-01-13 09:32:18 +10:30
lguest lguest: Make sure interrupt is allocated ok by lguest_setup_irq 2012-01-12 15:44:47 +10:30
lib Merge branches 'sched-urgent-for-linus', 'perf-urgent-for-linus' and 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-01-19 14:53:06 -08:00
math-emu
mm Merge branches 'core-urgent-for-linus', 'perf-urgent-for-linus', 'sched-urgent-for-linus' and 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-02-02 11:11:13 -08:00
net net: bpf_jit: fix divide by 0 generation 2012-01-18 16:04:26 -05:00
oprofile
pci x86/PCI: build amd_bus.o only when CONFIG_AMD_NB=y 2012-01-12 07:54:18 -08:00
platform x86/uv: Fix uninitialized spinlocks 2012-01-26 10:58:34 +01:00
power
syscalls
tools
um uml: fix compile for x86-64 2012-01-18 19:26:11 -08:00
vdso
video
xen Merge commit 'v3.3-rc1' into stable/for-linus-fixes-3.3 2012-01-27 11:14:02 -05:00
.gitignore x86/kprobes: Add arch/x86/tools/insn_sanity to .gitignore 2012-01-16 08:21:59 +01:00
Kbuild
Kconfig x86/numachip: Drop unnecessary conflict with EDAC 2012-01-26 11:03:03 +01:00
Kconfig.cpu mm,x86,um: move CMPXCHG_DOUBLE config option 2012-01-12 20:13:03 -08:00
Kconfig.debug Merge branch 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-01-11 19:13:40 -08:00
Makefile
Makefile.um
Makefile_32.cpu