diff options
| author | Michael S. Tsirkin <mst@redhat.com> | 2012-09-16 11:50:30 +0300 |
|---|---|---|
| committer | Marcelo Tosatti <mtosatti@redhat.com> | 2012-09-17 13:46:32 -0300 |
| commit | 9fc77441e5e1bf80b794cc546d2243ee9f4afb75 (patch) | |
| tree | 4661976f4fea7606a54b3f5276c0ecb45760979c /arch | |
| parent | 7454766f7bead388251aedee35a478356a7f4e72 (diff) | |
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 <mst@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/kvm/x86.c | 12 |
1 files changed, 9 insertions, 3 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index c4d451ed1573..19047eafa38d 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -6016,7 +6016,9 @@ int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu) int r; vcpu->arch.mtrr_state.have_fixed = 1; - vcpu_load(vcpu); + r = vcpu_load(vcpu); + if (r) + return r; r = kvm_arch_vcpu_reset(vcpu); if (r == 0) r = kvm_mmu_setup(vcpu); @@ -6027,9 +6029,11 @@ int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu) void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu) { + int r; vcpu->arch.apf.msr_val = 0; - vcpu_load(vcpu); + r = vcpu_load(vcpu); + BUG_ON(r); kvm_mmu_unload(vcpu); vcpu_put(vcpu); @@ -6275,7 +6279,9 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) static void kvm_unload_vcpu_mmu(struct kvm_vcpu *vcpu) { - vcpu_load(vcpu); + int r; + r = vcpu_load(vcpu); + BUG_ON(r); kvm_mmu_unload(vcpu); vcpu_put(vcpu); } |