linux/arch
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
..
alpha Merge branch 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci 2012-01-11 18:50:26 -08:00
arm arm-soc fixes for 3.3-rc 2012-02-04 12:11:40 -08:00
avr32 avr32: select generic atomic64_t support 2012-02-03 16:16:40 -08:00
blackfin Merge branch 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci 2012-01-11 18:50:26 -08:00
c6x C6X: replace tick_nohz_stop/restart_sched_tick calls 2012-01-08 15:13:16 -05:00
cris lib: use generic pci_iomap on all architectures 2012-01-10 18:04:27 -08:00
frv Merge branch 'for-next' of git://git.infradead.org/users/dhowells/linux-headers 2012-01-14 18:03:30 -08:00
h8300 Merge branch 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci 2012-01-11 18:50:26 -08:00
hexagon lib: move GENERIC_IOMAP to lib/Kconfig 2011-11-24 22:21:19 +02:00
ia64 Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux 2012-01-18 15:51:48 -08:00
m32r Merge branch 'for-next' of git://git.infradead.org/users/dhowells/linux-headers 2012-01-14 18:03:30 -08:00
m68k Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k 2012-01-26 12:43:57 -08:00
microblaze Revert "microblaze: Add topology init" 2012-01-31 09:06:52 +01:00
mips Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit 2012-01-17 16:41:31 -08:00
mn10300 Merge branch 'for-next' of git://git.infradead.org/users/dhowells/linux-headers 2012-01-14 18:03:30 -08:00
openrisc Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild 2012-01-16 14:34:54 -08:00
parisc parisc, exec: remove redundant set_fs(USER_DS) 2012-01-12 20:13:04 -08:00
powerpc powerpc: Fix build on some non-freescale platforms 2012-01-25 13:33:22 +11:00
s390 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux 2012-01-30 09:02:10 -08:00
score score: fix off-by-one index into syscall table 2012-01-23 08:38:49 -08:00
sh Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit 2012-01-17 16:41:31 -08:00
sparc lib: Fix multiple definitions of clz_tab 2012-02-02 10:34:23 +11:00
tile Merge branch 'for-next' of git://git.infradead.org/users/dhowells/linux-headers 2012-01-14 18:03:30 -08:00
um Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit 2012-01-17 16:41:31 -08:00
unicore32 Merge branch 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci 2012-01-11 18:50:26 -08:00
x86 x86: Specify a size for the cmp in the NMI handler 2012-02-20 19:45:26 -05:00
xtensa xtensa: fix memscan() 2012-02-03 16:16:40 -08:00
.gitignore
Kconfig mm,x86,um: move CMPXCHG_DOUBLE config option 2012-01-12 20:13:03 -08:00