mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
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


  parent reply	other threads:[~2026-07-28  0:36 UTC|newest]

Thread overview: 45+ 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
2026-08-01  6:10   ` Yosry Ahmed
2026-07-28  0:35 ` [PATCH v1 03/28] KVM: VMX: Generalize VPID allocation to be vendor-neutral Yosry Ahmed
2026-08-01  6:13   ` 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
2026-08-01  6:15   ` 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
2026-08-01  6:18   ` Yosry Ahmed
2026-08-01  6:25   ` 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
2026-08-01  6:34   ` Yosry Ahmed
2026-08-05  0:26     ` Yosry Ahmed
2026-08-05 15:25       ` 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
2026-08-01  6:41   ` Yosry Ahmed
2026-08-03 17:21     ` Yosry Ahmed
2026-08-03 22:27       ` Sean Christopherson
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
2026-08-01  6:36   ` 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
2026-07-30 21:52     ` Yosry Ahmed
2026-08-01  6:39     ` Yosry Ahmed

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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

all inboxes | Powered by JetHome®