diff options
Diffstat (limited to 'arch/x86/lib/usercopy_64.c')
-rw-r--r-- | arch/x86/lib/usercopy_64.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/arch/x86/lib/usercopy_64.c b/arch/x86/lib/usercopy_64.c index f4df6e7c718b..847d12945998 100644 --- a/arch/x86/lib/usercopy_64.c +++ b/arch/x86/lib/usercopy_64.c @@ -16,6 +16,8 @@ do { \ long __d0, __d1, __d2; \ might_sleep(); \ + if (current->mm) \ + might_lock_read(¤t->mm->mmap_sem); \ __asm__ __volatile__( \ " testq %1,%1\n" \ " jz 2f\n" \ @@ -65,6 +67,8 @@ unsigned long __clear_user(void __user *addr, unsigned long size) { long __d0; might_sleep(); + if (current->mm) + might_lock_read(¤t->mm->mmap_sem); /* no memory constraint because it doesn't change any memory gcc knows about */ asm volatile( |