From 9fc77441e5e1bf80b794cc546d2243ee9f4afb75 Mon Sep 17 00:00:00 2001 From: "Michael S. Tsirkin" Date: Sun, 16 Sep 2012 11:50:30 +0300 Subject: KVM: make processes waiting on vcpu mutex killable vcpu mutex can be held for unlimited time so taking it with mutex_lock on an ioctl is wrong: one process could be passed a vcpu fd and call this ioctl on the vcpu used by another process, it will then be unkillable until the owner exits. Call mutex_lock_killable instead and return status. Note: mutex_lock_interruptible would be even nicer, but I am not sure all users are prepared to handle EINTR from these ioctls. They might misinterpret it as an error. Cleanup paths expect a vcpu that can't be used by any userspace so this will always succeed - catch bugs by calling BUG_ON. Catch callers that don't check return state by adding __must_check. Signed-off-by: Michael S. Tsirkin Signed-off-by: Marcelo Tosatti --- include/linux/kvm_host.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include') diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 40791930bc1..80bfc880921 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -408,7 +408,7 @@ static inline struct kvm_vcpu *kvm_get_vcpu(struct kvm *kvm, int i) int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id); void kvm_vcpu_uninit(struct kvm_vcpu *vcpu); -void vcpu_load(struct kvm_vcpu *vcpu); +int __must_check vcpu_load(struct kvm_vcpu *vcpu); void vcpu_put(struct kvm_vcpu *vcpu); int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align, -- cgit v1.2.3-70-g09d2