KVM: Disable pagefaults during copy_from_user_inatomic()
With CONFIG_PREEMPT=n, this is needed in order to disable the fault-in
code from sleeping.
Signed-off-by: Andrea Arcangeli <andrea@qumranet.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 7972e3a..cf6df51 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -554,7 +554,9 @@
addr = gfn_to_hva(kvm, gfn);
if (kvm_is_error_hva(addr))
return -EFAULT;
+ pagefault_disable();
r = __copy_from_user_inatomic(data, (void __user *)addr + offset, len);
+ pagefault_enable();
if (r)
return -EFAULT;
return 0;