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From: Maxim Levitsky <mlevitsk@redhat.com>
To: kvm@vger.kernel.org
Cc: Jim Mattson <jmattson@google.com>,
	linux-kernel@vger.kernel.org, Wanpeng Li <wanpengli@tencent.com>,
	Borislav Petkov <bp@alien8.de>, Joerg Roedel <joro@8bytes.org>,
	Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>,
	"H. Peter Anvin" <hpa@zytor.com>,
	Paolo Bonzini <pbonzini@redhat.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>,
	Vitaly Kuznetsov <vkuznets@redhat.com>,
	Sean Christopherson <seanjc@google.com>,
	x86@kernel.org (maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)),
	Maxim Levitsky <mlevitsk@redhat.com>
Subject: [PATCH v4 15/16] KVM: SVM: call avic_vcpu_load/avic_vcpu_put when enabling/disabling AVIC
Date: Tue, 10 Aug 2021 23:52:50 +0300	[thread overview]
Message-ID: <20210810205251.424103-16-mlevitsk@redhat.com> (raw)
In-Reply-To: <20210810205251.424103-1-mlevitsk@redhat.com>

Currently it is possible to have the following scenario:

1. AVIC is disabled by svm_refresh_apicv_exec_ctrl
2. svm_vcpu_blocking calls avic_vcpu_put which does nothing
3. svm_vcpu_unblocking enables the AVIC (due to KVM_REQ_APICV_UPDATE)
   and then calls avic_vcpu_load
4. warning is triggered in avic_vcpu_load since
   AVIC_PHYSICAL_ID_ENTRY_IS_RUNNING_MASK was never cleared

While it is possible to just remove the warning, it seems to be more robust
to fully disable/enable AVIC in svm_refresh_apicv_exec_ctrl by calling the
avic_vcpu_load/avic_vcpu_put

Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
---
 arch/x86/kvm/svm/avic.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/arch/x86/kvm/svm/avic.c b/arch/x86/kvm/svm/avic.c
index e7728b16a46f..01c0e83e1b71 100644
--- a/arch/x86/kvm/svm/avic.c
+++ b/arch/x86/kvm/svm/avic.c
@@ -651,6 +651,11 @@ void svm_refresh_apicv_exec_ctrl(struct kvm_vcpu *vcpu)
 	}
 	vmcb_mark_dirty(vmcb, VMCB_AVIC);
 
+	if (activated)
+		avic_vcpu_load(vcpu, vcpu->cpu);
+	else
+		avic_vcpu_put(vcpu);
+
 	svm_set_pi_irte_mode(vcpu, activated);
 }
 
-- 
2.26.3


  parent reply	other threads:[~2021-08-10 20:54 UTC|newest]

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-08-10 20:52 [PATCH v4 00/16] My AVIC patch queue Maxim Levitsky
2021-08-10 20:52 ` [PATCH v4 01/16] Revert "KVM: x86/mmu: Allow zap gfn range to operate under the mmu read lock" Maxim Levitsky
2021-08-10 20:52 ` [PATCH v4 02/16] KVM: x86/mmu: fix parameters to kvm_flush_remote_tlbs_with_address Maxim Levitsky
2021-08-10 20:52 ` [PATCH v4 03/16] KVM: x86/mmu: add comment explaining arguments to kvm_zap_gfn_range Maxim Levitsky
2021-08-10 20:52 ` [PATCH v4 04/16] KVM: x86/mmu: bump mmu notifier count in kvm_zap_gfn_range Maxim Levitsky
2021-08-10 20:52 ` [PATCH v4 05/16] KVM: x86/mmu: rename try_async_pf to kvm_faultin_pfn Maxim Levitsky
2021-08-10 20:52 ` [PATCH v4 06/16] KVM: x86/mmu: allow kvm_faultin_pfn to return page fault handling code Maxim Levitsky
2021-08-10 20:52 ` [PATCH v4 07/16] KVM: x86/mmu: allow APICv memslot to be enabled but invisible Maxim Levitsky
2021-08-10 20:52 ` [PATCH v4 08/16] KVM: x86: don't disable APICv memslot when inhibited Maxim Levitsky
2021-08-10 20:52 ` [PATCH v4 09/16] KVM: x86: APICv: fix race in kvm_request_apicv_update on SVM Maxim Levitsky
2021-08-10 20:52 ` [PATCH v4 10/16] KVM: SVM: add warning for mistmatch between AVIC vcpu state and AVIC inhibition Maxim Levitsky
2021-08-10 20:52 ` [PATCH v4 11/16] KVM: x86: hyper-v: Deactivate APICv only when AutoEOI feature is in use Maxim Levitsky
2021-08-10 20:52 ` [PATCH v4 12/16] KVM: SVM: remove svm_toggle_avic_for_irq_window Maxim Levitsky
2021-08-10 20:52 ` [PATCH v4 13/16] KVM: SVM: avoid refreshing avic if its state didn't change Maxim Levitsky
2021-08-10 20:52 ` [PATCH v4 14/16] KVM: SVM: move check for kvm_vcpu_apicv_active outside of avic_vcpu_{put|load} Maxim Levitsky
2021-08-10 20:52 ` Maxim Levitsky [this message]
2021-08-10 20:52 ` [PATCH v4 16/16] KVM: SVM: AVIC: drop unsupported AVIC base relocation code Maxim Levitsky
2021-08-10 21:21 ` [PATCH v4 00/16] My AVIC patch queue Maxim Levitsky
2021-08-11  8:06   ` Paolo Bonzini

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