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Diffstat (limited to 'arch/x86/kernel/alternative.c')
-rw-r--r--arch/x86/kernel/alternative.c23
1 files changed, 14 insertions, 9 deletions
diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c
index a84ac7b570e..4c80f155743 100644
--- a/arch/x86/kernel/alternative.c
+++ b/arch/x86/kernel/alternative.c
@@ -414,9 +414,17 @@ void __init alternative_instructions(void)
that might execute the to be patched code.
Other CPUs are not running. */
stop_nmi();
-#ifdef CONFIG_X86_MCE
- stop_mce();
-#endif
+
+ /*
+ * Don't stop machine check exceptions while patching.
+ * MCEs only happen when something got corrupted and in this
+ * case we must do something about the corruption.
+ * Ignoring it is worse than a unlikely patching race.
+ * Also machine checks tend to be broadcast and if one CPU
+ * goes into machine check the others follow quickly, so we don't
+ * expect a machine check to cause undue problems during to code
+ * patching.
+ */
apply_alternatives(__alt_instructions, __alt_instructions_end);
@@ -456,9 +464,6 @@ void __init alternative_instructions(void)
(unsigned long)__smp_locks_end);
restart_nmi();
-#ifdef CONFIG_X86_MCE
- restart_mce();
-#endif
}
/**
@@ -498,12 +503,12 @@ void *text_poke_early(void *addr, const void *opcode, size_t len)
*/
void *__kprobes text_poke(void *addr, const void *opcode, size_t len)
{
- unsigned long flags;
char *vaddr;
int nr_pages = 2;
struct page *pages[2];
int i;
+ might_sleep();
if (!core_kernel_text((unsigned long)addr)) {
pages[0] = vmalloc_to_page(addr);
pages[1] = vmalloc_to_page(addr + PAGE_SIZE);
@@ -517,9 +522,9 @@ void *__kprobes text_poke(void *addr, const void *opcode, size_t len)
nr_pages = 1;
vaddr = vmap(pages, nr_pages, VM_MAP, PAGE_KERNEL);
BUG_ON(!vaddr);
- local_irq_save(flags);
+ local_irq_disable();
memcpy(&vaddr[(unsigned long)addr & ~PAGE_MASK], opcode, len);
- local_irq_restore(flags);
+ local_irq_enable();
vunmap(vaddr);
sync_core();
/* Could also do a CLFLUSH here to speed up CPU recovery; but