The ioctl KVM_IA64_VCPU_GET_STACK does not set the error code if copy_to_user() fail, and 0 will be return, we should use -EFAULT instead of 0 in this case, so this patch fixed it. Signed-off-by: Wei Yongjun <yjwei@xxxxxxxxxxxxxx> --- arch/ia64/kvm/kvm-ia64.c | 4 +++- 1 files changed, 3 insertions(+), 1 deletions(-) diff --git a/arch/ia64/kvm/kvm-ia64.c b/arch/ia64/kvm/kvm-ia64.c index 26e0e08..bc07c81 100644 --- a/arch/ia64/kvm/kvm-ia64.c +++ b/arch/ia64/kvm/kvm-ia64.c @@ -1535,8 +1535,10 @@ long kvm_arch_vcpu_ioctl(struct file *filp, goto out; if (copy_to_user(user_stack, stack, - sizeof(struct kvm_ia64_vcpu_stack))) + sizeof(struct kvm_ia64_vcpu_stack))) { + r = -EFAULT; goto out; + } break; } -- 1.6.3.3 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html