From acb5451789f21ad51215897bb8f9306a05e8acd4 Mon Sep 17 00:00:00 2001 From: Gleb Natapov Date: Thu, 15 Apr 2010 21:03:50 +0300 Subject: KVM: prevent spurious exit to userspace during task switch emulation. If kvm_task_switch() fails code exits to userspace without specifying exit reason, so the previous exit reason is reused by userspace. Fix this by specifying exit reason correctly. Signed-off-by: Gleb Natapov Signed-off-by: Marcelo Tosatti --- arch/x86/kvm/svm.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) (limited to 'arch/x86/kvm/svm.c') diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index 78af52222fd..ab78eb8ba89 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -2266,8 +2266,14 @@ static int task_switch_interception(struct vcpu_svm *svm) (int_vec == OF_VECTOR || int_vec == BP_VECTOR))) skip_emulated_instruction(&svm->vcpu); - return kvm_task_switch(&svm->vcpu, tss_selector, reason, - has_error_code, error_code); + if (kvm_task_switch(&svm->vcpu, tss_selector, reason, + has_error_code, error_code) == EMULATE_FAIL) { + svm->vcpu.run->exit_reason = KVM_EXIT_INTERNAL_ERROR; + svm->vcpu.run->internal.suberror = KVM_INTERNAL_ERROR_EMULATION; + svm->vcpu.run->internal.ndata = 0; + return 0; + } + return 1; } static int cpuid_interception(struct vcpu_svm *svm) -- cgit v1.2.3-18-g5258