X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=arch%2Fx86%2Fkernel%2Falternative.c;h=4c80f15574335d6b02bc93a7ed797c088c1da6c2;hb=712b0006bf3a9ed0b14a56c3291975e582127766;hp=a84ac7b570e6bb4582788da74a4c570e28fd65e9;hpb=9649745c8670eacc671e9cff72c5c1e346e13036;p=linux-2.6-omap-h63xx.git

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