From: Jan Kiszka <jan.kiszka@siemens.com>
To: Alexander Graf <agraf@suse.de>
Cc: kvm@vger.kernel.org
Subject: Re: [PATCH 2/5] Don't call svm_complete_interrupts for nested guests
Date: Fri, 18 Sep 2009 15:39:58 +0200 [thread overview]
Message-ID: <4AB38DAE.40604@siemens.com> (raw)
In-Reply-To: <1253278832-31803-3-git-send-email-agraf@suse.de>
Alexander Graf wrote:
> SVM has some cleanup code, that tries to reinject interrupts and exceptions
> when the guest didn't manage to deal with them yet. It basically transfers
> them to KVM internal state.
>
> Unfortunately, the internal state is reserved for the L1 guest state, so we
> shouldn't try to go through that logic when running a nested guest.
>
> When doing something the host KVM can handle, let's just reinject the event
> into the L2 guest, because we didn't touch its state anyways.
>
> Signed-off-by: Alexander Graf <agraf@suse.de>
> ---
> arch/x86/kvm/svm.c | 18 ++++++++++++++----
> 1 files changed, 14 insertions(+), 4 deletions(-)
>
> diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
> index f12a669..61efd13 100644
> --- a/arch/x86/kvm/svm.c
> +++ b/arch/x86/kvm/svm.c
> @@ -2349,7 +2349,10 @@ static int handle_exit(struct kvm_vcpu *vcpu)
> trace_kvm_exit(exit_code, svm->vmcb->save.rip);
>
> if (is_nested(svm)) {
> + struct vmcb_control_area *control = &svm->vmcb->control;
> int vmexit;
> + int type;
> + int vec;
>
> nsvm_printk("nested handle_exit: 0x%x | 0x%lx | 0x%lx | 0x%lx\n",
> exit_code, svm->vmcb->control.exit_info_1,
> @@ -2362,9 +2365,18 @@ static int handle_exit(struct kvm_vcpu *vcpu)
>
> if (vmexit == NESTED_EXIT_DONE)
> return 1;
> - }
>
> - svm_complete_interrupts(svm);
> + type = control->exit_int_info & SVM_EXITINTINFO_TYPE_MASK;
> + vec = control->exit_int_info & SVM_EXITINTINFO_VEC_MASK;
> + if ((type == SVM_EXITINTINFO_TYPE_INTR) ||
> + ((type == SVM_EXITINTINFO_TYPE_EXEPT) && !kvm_exception_is_soft(vec))) {
> + control->event_inj = control->exit_int_info;
> + control->event_inj_err = control->exit_int_info_err;
> + }
> + } else {
> + /* Don't interpret exit_info for nested guests */
Doesn't this comment belong to the block above?
> + svm_complete_interrupts(svm);
> + }
>
> if (npt_enabled) {
> int mmu_reload = 0;
> @@ -2602,8 +2614,6 @@ static void svm_complete_interrupts(struct vcpu_svm *svm)
> case SVM_EXITINTINFO_TYPE_EXEPT:
> /* In case of software exception do not reinject an exception
> vector, but re-execute and instruction instead */
> - if (is_nested(svm))
> - break;
> if (kvm_exception_is_soft(vector))
> break;
> if (exitintinfo & SVM_EXITINTINFO_VALID_ERR) {
Jan
--
Siemens AG, Corporate Technology, CT SE 2
Corporate Competence Center Embedded Linux
next prev parent reply other threads:[~2009-09-18 13:39 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-09-18 13:00 [PATCH 0/5] Nested SVM Interrupt Fixes Alexander Graf
2009-09-18 13:00 ` [PATCH 1/5] Implement #NMI exiting for nested SVM Alexander Graf
2009-09-18 13:00 ` [PATCH 2/5] Don't call svm_complete_interrupts for nested guests Alexander Graf
2009-09-18 13:00 ` [PATCH 3/5] Don't #VMEXIT(INTR) if we still have event_inj waiting Alexander Graf
2009-09-18 13:00 ` [PATCH 4/5] Don't bail when injecting an event in nested SVM Alexander Graf
2009-09-18 13:00 ` [PATCH 5/5] Notify nested hypervisor of lost event injections Alexander Graf
2009-09-23 1:22 ` Joerg Roedel
2009-09-27 14:18 ` Joerg Roedel
2009-09-23 1:39 ` [PATCH 3/5] Don't #VMEXIT(INTR) if we still have event_inj waiting Joerg Roedel
2009-09-23 8:09 ` Alexander Graf
2009-09-18 13:39 ` Jan Kiszka [this message]
2009-09-23 1:26 ` [PATCH 2/5] Don't call svm_complete_interrupts for nested guests Joerg Roedel
2009-09-23 8:04 ` Alexander Graf
2009-09-23 8:05 ` Alexander Graf
2009-09-23 8:28 ` Gleb Natapov
2009-09-18 13:33 ` [PATCH 1/5] Implement #NMI exiting for nested SVM Jan Kiszka
2009-09-18 15:44 ` Alexander Graf
2009-09-18 16:01 ` Jan Kiszka
2009-09-23 1:06 ` Joerg Roedel
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