commit 3ee1afa308f2a38e5d1e2ad3752ad7abcf480da1
author Nick Piggin <npiggin@suse.de> Wed Sep 10 13:37:17 2008 +0200
committer Ingo Molnar <mingo@elte.hu> Thu Sep 11 09:44:21 2008 +0200
tree 914e0f3bbd32a387cf6095c6955369fa8da7ebf6
parent c10d38dda1774ed4540380333cabd229eff37094

x86: some lock annotations for user copy paths, v2

 - introduce might_fault()
 - handle the atomic user copy paths correctly

[ mingo@elte.hu: move might_sleep() outside of in_atomic(). ]
Signed-off-by: Nick Piggin <npiggin@suse.de>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

arch/x86/lib/usercopy_64.c

diff --git a/arch/x86/lib/usercopy_64.c b/arch/x86/lib/usercopy_64.c
index 847d129..64d6c84 100644
--- a/arch/x86/lib/usercopy_64.c
+++ b/arch/x86/lib/usercopy_64.c
@@ -15,9 +15,7 @@
 #define __do_strncpy_from_user(dst,src,count,res)			   \
 do {									   \
 	long __d0, __d1, __d2;						   \
-	might_sleep();							   \
-	if (current->mm)						   \
-		might_lock_read(&current->mm->mmap_sem);		   \
+	might_fault();							   \
 	__asm__ __volatile__(						   \
 		"	testq %1,%1\n"					   \
 		"	jz 2f\n"					   \
@@ -66,9 +64,7 @@
 unsigned long __clear_user(void __user *addr, unsigned long size)
 {
 	long __d0;
-	might_sleep();
-	if (current->mm)
-		might_lock_read(&current->mm->mmap_sem);
+	might_fault();
 	/* no memory constraint because it doesn't change any memory gcc knows
 	   about */
 	asm volatile(