From: Yosry Ahmed <yosry@kernel.org>
To: Sean Christopherson <seanjc@google.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>,
Jim Mattson <jmattson@google.com>,
Maxim Levitsky <mlevitsk@redhat.com>,
Vitaly Kuznetsov <vkuznets@redhat.com>,
Tom Lendacky <thomas.lendacky@amd.com>,
kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
Yosry Ahmed <yosry@kernel.org>
Subject: [PATCH v1 17/28] KVM: nSVM: Always switch VMCB before leaving guest mode
Date: Tue, 28 Jul 2026 00:35:46 +0000 [thread overview]
Message-ID: <20260728003557.1136583-18-yosry@kernel.org> (raw)
In-Reply-To: <20260728003557.1136583-1-yosry@kernel.org>
Move svm_switch_vmcb() calls ahead of leave_guest_mode(), as nothing
between the calls depends on svm->vmcb being set to vmcb01. This makes
the nested VM-Exit path consistent with the nested VM-Enter path, and
having the calls to svm_switch_vmcb() and leave_guest_mode() close makes
it easier to reason about incoming changes that depend on both VMCB and
guest_mode context.
No functional change intended.
Signed-off-by: Yosry Ahmed <yosry@kernel.org>
---
arch/x86/kvm/svm/nested.c | 7 ++-----
1 file changed, 2 insertions(+), 5 deletions(-)
diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c
index a6a49a5e0d90a..410d0f1aaa63c 100644
--- a/arch/x86/kvm/svm/nested.c
+++ b/arch/x86/kvm/svm/nested.c
@@ -1325,7 +1325,7 @@ void nested_svm_vmexit(struct vcpu_svm *svm)
if (nested_svm_vmexit_update_vmcb12(vcpu))
kvm_make_request(KVM_REQ_TRIPLE_FAULT, vcpu);
- /* Exit Guest-Mode */
+ svm_switch_vmcb(svm, &svm->vmcb01);
leave_guest_mode(vcpu);
svm_pmu_handle_nested_transition(svm);
@@ -1352,8 +1352,6 @@ void nested_svm_vmexit(struct vcpu_svm *svm)
if (guest_cpu_cap_has(vcpu, X86_FEATURE_ERAPS))
vmcb01->control.erap_ctl |= ERAP_CONTROL_CLEAR_RAP;
- svm_switch_vmcb(svm, &svm->vmcb01);
-
/*
* Rules for synchronizing int_ctl bits from vmcb02 to vmcb01:
*
@@ -1537,6 +1535,7 @@ void svm_leave_nested(struct kvm_vcpu *vcpu)
vcpu->arch.nested_run_pending = 0;
svm->nested.vmcb12_gpa = INVALID_GPA;
+ svm_switch_vmcb(svm, &svm->vmcb01);
leave_guest_mode(vcpu);
/*
@@ -1548,8 +1547,6 @@ void svm_leave_nested(struct kvm_vcpu *vcpu)
*/
__svm_pmu_handle_nested_transition(svm, true);
- svm_switch_vmcb(svm, &svm->vmcb01);
-
nested_svm_transition_tlb_flush(vcpu);
nested_svm_uninit_mmu_context(vcpu);
--
2.55.0.229.g6434b31f56-goog
next prev parent reply other threads:[~2026-07-28 0:36 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-07-28 0:35 [PATCH v1 00/28] KVM: nSVM: Optimize nSVM TLB flushes Yosry Ahmed
2026-07-28 0:35 ` [PATCH v1 01/28] KVM: nSVM: Flush the TLB after forcefully leaving nested Yosry Ahmed
2026-07-28 0:35 ` [PATCH v1 02/28] KVM: SVM: Document number of ASIDs CPUID setting Yosry Ahmed
2026-07-28 0:35 ` [PATCH v1 03/28] KVM: VMX: Generalize VPID allocation to be vendor-neutral Yosry Ahmed
2026-07-28 0:35 ` [PATCH v1 04/28] KVM: x86/mmu: Support specifying reserved TLB tags Yosry Ahmed
2026-07-28 0:35 ` [PATCH v1 05/28] KVM: SVM: Add helpers to set/clear ASID flush in VMCB Yosry Ahmed
2026-07-28 0:35 ` [PATCH v1 06/28] KVM: SVM: Fallback to flush everything if FLUSHBYASID is not available Yosry Ahmed
2026-07-28 0:35 ` [PATCH v1 07/28] KVM: SVM: Duplicate pre-run ASID check for SEV and non-SEV guests Yosry Ahmed
2026-07-28 0:35 ` [PATCH v1 08/28] KVM: SEV: Do ASID initialization at VMCB initialization Yosry Ahmed
2026-07-28 0:35 ` [PATCH v1 09/28] KVM: SEV: Expose sev_get_asid() outside of sev.c Yosry Ahmed
2026-07-28 0:35 ` [PATCH v1 10/28] KVM: SVM: Use a static ASID per vCPU Yosry Ahmed
2026-07-28 0:35 ` [PATCH v1 11/28] KVM: SVM: Only flush the fallback ASID when used by a different vCPU Yosry Ahmed
2026-07-28 0:35 ` [PATCH v1 12/28] KVM: nSVM: Add a placeholder ASID for L2 Yosry Ahmed
2026-07-28 0:35 ` [PATCH v1 13/28] KVM: x86: hyper-v: Rename kvm_hv_vcpu_purge_flush_tlb() Yosry Ahmed
2026-07-28 0:35 ` [PATCH v1 14/28] KVM: x86: hyper-v: Allow puring all TLB flush FIFOs Yosry Ahmed
2026-07-28 0:35 ` [PATCH v1 15/28] KVM: nSVM: Drop svm->nested.initialized Yosry Ahmed
2026-07-28 0:35 ` [PATCH v1 16/28] KVM: nSVM: Flush both L1 and L2 ASIDs on KVM_REQ_TLB_FLUSH Yosry Ahmed
2026-07-28 0:35 ` Yosry Ahmed [this message]
2026-07-28 0:35 ` [PATCH v1 18/28] KVM: nSVM: Split nested_svm_transition_tlb_flush() into entry/exit fns Yosry Ahmed
2026-07-28 0:35 ` [PATCH v1 19/28] KVM: nSVM: Service local TLB flushes before nested transitions Yosry Ahmed
2026-07-28 0:35 ` [PATCH v1 20/28] KVM: nSVM: Handle nested TLB flush requests through TLB_CONTROL Yosry Ahmed
2026-07-28 0:35 ` [PATCH v1 21/28] KVM: nSVM: Flush the TLB if L1 changes L2's ASID in vmcb12 Yosry Ahmed
2026-07-28 0:35 ` [PATCH v1 22/28] KVM: nSVM: Do not reset TLB_CONTROL in vmcb02 on nested VM-Enter Yosry Ahmed
2026-07-28 0:35 ` [PATCH v1 23/28] KVM: x86/mmu: Rename __kvm_mmu_invalidate_addr() to kvm_mmu_sync_addr() Yosry Ahmed
2026-07-28 0:35 ` [PATCH v1 24/28] KVM: x86/mmu: Refactor kvm_mmu_invlpg() to allow skipping the GVA flush Yosry Ahmed
2026-07-28 0:35 ` [PATCH v1 25/28] KVM: nSVM: Flush L2's ASID when emulating INVLPGA Yosry Ahmed
2026-07-28 0:35 ` [PATCH v1 26/28] KVM: nSVM: Flush the ASID on nested transitions if shared by L1 and L2 Yosry Ahmed
2026-07-28 0:35 ` [PATCH v1 27/28] KVM: nSVM: Use different ASIDs for " Yosry Ahmed
2026-07-28 0:35 ` [PATCH v1 28/28] KVM: selftests: Add a test for nested TLB flushes Yosry Ahmed
2026-07-28 1:05 ` [PATCH v1 00/28] KVM: nSVM: Optimize nSVM " Yosry Ahmed
2026-07-28 1:18 ` Sean Christopherson
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20260728003557.1136583-18-yosry@kernel.org \
--to=yosry@kernel.org \
--cc=jmattson@google.com \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mlevitsk@redhat.com \
--cc=pbonzini@redhat.com \
--cc=seanjc@google.com \
--cc=thomas.lendacky@amd.com \
--cc=vkuznets@redhat.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.