linux/arch/x86
Frederic Weisbecker 6c0aca288e x86: Ignore trap bits on single step exceptions
When a single step exception fires, the trap bits, used to
signal hardware breakpoints, are in a random state.

These trap bits might be set if another exception will follow,
like a breakpoint in the next instruction, or a watchpoint in the
previous one. Or there can be any junk there.

So if we handle these trap bits during the single step exception,
we are going to handle an exception twice, or we are going to
handle junk.

Just ignore them in this case.

This fixes https://bugzilla.kernel.org/show_bug.cgi?id=21332

Reported-by: Michael Stefaniuc <mstefani@redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Maciej Rutecki <maciej.rutecki@gmail.com>
Cc: Alexandre Julliard <julliard@winehq.org>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: All since 2.6.33.x <stable@kernel.org>
2010-11-12 14:51:01 +01:00
..
boot
configs
crypto
ia32
include/asm Merge branch 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2010-10-27 18:48:00 -07:00
kernel x86: Ignore trap bits on single step exceptions 2010-11-12 14:51:01 +01:00
kvm Merge branch 'kvm-updates/2.6.37' of git://git.kernel.org/pub/scm/virt/kvm/kvm 2010-10-24 12:47:25 -07:00
lguest
lib
math-emu
mm Remove duplicate includes from many files 2010-10-27 18:03:18 -07:00
oprofile Merge branch 'x86' of git://git.kernel.org/pub/scm/linux/kernel/git/rric/oprofile into perf/urgent 2010-10-25 19:17:32 +02:00
pci
power
tools
vdso
video
xen Merge branch 'akpm-incoming-2' 2010-10-27 18:42:52 -07:00
.gitignore
Kbuild
Kconfig Merge branch 'linus' into x86/urgent 2010-10-25 19:38:52 +02:00
Kconfig.cpu
Kconfig.debug Merge branch 'x86-irq-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2010-10-22 08:54:21 -07:00
Makefile
Makefile_32.cpu jump label: Add work around to i386 gcc asm goto bug 2010-10-29 14:45:29 -04:00