summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorZachary Amsden <zach@vmware.com>2006-10-20 14:18:51 -0700
committerChris Wright <chrisw@sous-sol.org>2006-11-03 17:33:47 -0800
commitd758e2151487a13f2b6c726d0ba3781bbddf3e18 (patch)
treedf00d7a7755d7dd0dd294f4c9c3a1114860d6718
parent6c7e1a3d3d1b85ebbec3c33fc9c728ad3be4846f (diff)
[PATCH] Fix potential interrupts during alternative patching
Interrupts must be disabled during alternative instruction patching. On systems with high timer IRQ rates, or when running in an emulator, timing differences can result in random kernel panics because of running partially patched instructions. This doesn't yet fix NMIs, which requires extricating the patch code from the late bug checking and is logically separate (and also less likely to cause problems). Signed-off-by: Zachary Amsden <zach@vmware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Chris Wright <chrisw@sous-sol.org>
-rw-r--r--arch/i386/kernel/alternative.c4
1 files changed, 4 insertions, 0 deletions
diff --git a/arch/i386/kernel/alternative.c b/arch/i386/kernel/alternative.c
index 28ab80649764..583c238e17fb 100644
--- a/arch/i386/kernel/alternative.c
+++ b/arch/i386/kernel/alternative.c
@@ -344,6 +344,7 @@ void alternatives_smp_switch(int smp)
void __init alternative_instructions(void)
{
+ unsigned long flags;
if (no_replacement) {
printk(KERN_INFO "(SMP-)alternatives turned off\n");
free_init_pages("SMP alternatives",
@@ -351,6 +352,8 @@ void __init alternative_instructions(void)
(unsigned long)__smp_alt_end);
return;
}
+
+ local_irq_save(flags);
apply_alternatives(__alt_instructions, __alt_instructions_end);
/* switch to patch-once-at-boottime-only mode and free the
@@ -386,4 +389,5 @@ void __init alternative_instructions(void)
alternatives_smp_switch(0);
}
#endif
+ local_irq_restore(flags);
}