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author | Nadav Amit <namit@cs.technion.ac.il> | 2014-09-30 20:49:14 +0300 |
---|---|---|
committer | Paolo Bonzini <pbonzini@redhat.com> | 2014-11-03 12:07:23 +0100 |
commit | 6bdf06625d240361e92254143a123ab432e337f8 (patch) | |
tree | 4c3935eecde52126dd7fad88d3e4a5d3171fbcb1 /arch | |
parent | 394457a928e0f7ff121c375966f5ec1980dabc09 (diff) | |
download | linux-6bdf06625d240361e92254143a123ab432e337f8.tar.gz linux-6bdf06625d240361e92254143a123ab432e337f8.tar.bz2 linux-6bdf06625d240361e92254143a123ab432e337f8.zip |
KVM: x86: DR7.GD should be cleared upon any #DB exception
Intel SDM 17.2.4 (Debug Control Register (DR7)) says: "The processor clears the
GD flag upon entering to the debug exception handler." This sentence may be
misunderstood as if it happens only on #DB due to debug-register protection,
but it happens regardless to the cause of the #DB.
Fix the behavior to match both real hardware and Bochs.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch')
-rw-r--r-- | arch/x86/kvm/vmx.c | 2 | ||||
-rw-r--r-- | arch/x86/kvm/x86.c | 6 |
2 files changed, 6 insertions, 2 deletions
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 2627ffae919b..63e7cf18c1c8 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -5185,9 +5185,7 @@ static int handle_dr(struct kvm_vcpu *vcpu) vcpu->run->exit_reason = KVM_EXIT_DEBUG; return 0; } else { - vcpu->arch.dr7 &= ~DR7_GD; vcpu->arch.dr6 |= DR6_BD | DR6_RTM; - vmcs_writel(GUEST_DR7, vcpu->arch.dr7); kvm_queue_exception(vcpu, DB_VECTOR); return 1; } diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 0033df32a745..1ab7361594d5 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -5965,6 +5965,12 @@ static int inject_pending_event(struct kvm_vcpu *vcpu, bool req_int_win) __kvm_set_rflags(vcpu, kvm_get_rflags(vcpu) | X86_EFLAGS_RF); + if (vcpu->arch.exception.nr == DB_VECTOR && + (vcpu->arch.dr7 & DR7_GD)) { + vcpu->arch.dr7 &= ~DR7_GD; + kvm_update_dr7(vcpu); + } + kvm_x86_ops->queue_exception(vcpu, vcpu->arch.exception.nr, vcpu->arch.exception.has_error_code, vcpu->arch.exception.error_code, |