From 7d82714d4d1293edc57439c796750310866624b2 Mon Sep 17 00:00:00 2001 From: Alexander Graf Date: Fri, 9 Dec 2011 15:46:21 +0100 Subject: [PATCH] KVM: PPC: Book3s: PR: Disable preemption in vcpu_run MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit When entering the guest, we want to make sure we're not getting preempted away, so let's disable preemption on entry, but enable it again while handling guest exits. Reported-by: Jörg Sommer Signed-off-by: Alexander Graf Signed-off-by: Avi Kivity --- arch/powerpc/kvm/book3s_pr.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/arch/powerpc/kvm/book3s_pr.c b/arch/powerpc/kvm/book3s_pr.c index 203a7b7b58b9..19af2bf2b87d 100644 --- a/arch/powerpc/kvm/book3s_pr.c +++ b/arch/powerpc/kvm/book3s_pr.c @@ -517,6 +517,7 @@ int kvmppc_handle_exit(struct kvm_run *run, struct kvm_vcpu *vcpu, run->ready_for_interrupt_injection = 1; trace_kvm_book3s_exit(exit_nr, vcpu); + preempt_enable(); kvm_resched(vcpu); switch (exit_nr) { case BOOK3S_INTERRUPT_INST_STORAGE: @@ -761,6 +762,8 @@ int kvmppc_handle_exit(struct kvm_run *run, struct kvm_vcpu *vcpu, run->exit_reason = KVM_EXIT_INTR; r = -EINTR; } else { + preempt_disable(); + /* In case an interrupt came in that was triggered * from userspace (like DEC), we need to check what * to inject now! */ @@ -923,10 +926,13 @@ int kvmppc_vcpu_run(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu) #endif ulong ext_msr; + preempt_disable(); + /* Check if we can run the vcpu at all */ if (!vcpu->arch.sane) { kvm_run->exit_reason = KVM_EXIT_INTERNAL_ERROR; - return -EINVAL; + ret = -EINVAL; + goto out; } kvmppc_core_prepare_to_enter(vcpu); @@ -934,7 +940,8 @@ int kvmppc_vcpu_run(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu) /* No need to go into the guest when all we do is going out */ if (signal_pending(current)) { kvm_run->exit_reason = KVM_EXIT_INTR; - return -EINTR; + ret = -EINTR; + goto out; } /* Save FPU state in stack */ @@ -1004,6 +1011,8 @@ int kvmppc_vcpu_run(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu) current->thread.used_vsr = used_vsr; #endif +out: + preempt_enable(); return ret; } -- GitLab