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KVM: SVM: Stuff next_rip on emulated INT3 injection if NRIPS is supported

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If NRIPS is supported in hardware but disabled in KVM, set next_rip to
the next RIP when advancing RIP as part of emulating INT3 injection.
There is no flag to tell the CPU that KVM isn't using next_rip, and so
leaving next_rip is left as is will result in the CPU pushing garbage
onto the stack when vectoring the injected event.

Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Fixes: 66b7138f9136 ("KVM: SVM: Emulate nRIP feature when reinjecting INT3")
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com>
Message-Id: <cd328309a3b88604daa2359ad56f36cb565ce2d4.1651440202.git.maciej.szmigiero@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Sean Christopherson 2022-05-02 00:07:28 +02:00 committed by Paolo Bonzini
parent cd9e6da804
commit 3741aec4c3
1 changed files with 5 additions and 1 deletions
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6
arch/x86/kvm/svm/svm.c
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@ -392,6 +392,10 @@ static void svm_queue_exception(struct kvm_vcpu *vcpu)
*/
(void)svm_skip_emulated_instruction(vcpu);
rip = kvm_rip_read(vcpu);
if (boot_cpu_has(X86_FEATURE_NRIPS))
svm->vmcb->control.next_rip = rip;
svm->int3_rip = rip + svm->vmcb->save.cs.base;
svm->int3_injected = rip - old_rip;
}
@ -3709,7 +3713,7 @@ static void svm_complete_interrupts(struct kvm_vcpu *vcpu)
/*
* If NextRIP isn't enabled, KVM must manually advance RIP prior to
* injecting the soft exception/interrupt. That advancement needs to
* be unwound if vectoring didn't complete. Note, the _new_ event may
* be unwound if vectoring didn't complete. Note, the new event may
* not be the injected event, e.g. if KVM injected an INTn, the INTn
* hit a #NP in the guest, and the #NP encountered a #PF, the #NP will
* be the reported vectored event, but RIP still needs to be unwound.