From: Paolo Bonzini <pbonzini@redhat.com>
To: Sean Christopherson <sean.j.christopherson@intel.com>,
Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Wanpeng Li <wanpengli@tencent.com>,
Jim Mattson <jmattson@google.com>, Joerg Roedel <joro@8bytes.org>,
kvm@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 04/10] KVM: VMX: Fold vpid_sync_vcpu_{single,global}() into vpid_sync_context()
Date: Fri, 21 Feb 2020 18:28:07 +0100 [thread overview]
Message-ID: <c117f11a-bd57-2929-d5bc-47f4eaffe279@redhat.com> (raw)
In-Reply-To: <20200221153244.GD12665@linux.intel.com>
On 21/02/20 16:32, Sean Christopherson wrote:
>> In the original code it's only vpid_sync_vcpu_single() which has 'vpid
>> == 0' check, vpid_sync_vcpu_global() doesn't have it. So in the
>> hypothetical situation when cpu_has_vmx_invvpid_single() is false AND
>> we've e.g. exhausted our VPID space and allocate_vpid() returned zero,
>> the new code just won't do anything while the old one would've done
>> __invvpid(VMX_VPID_EXTENT_ALL_CONTEXT, 0, 0), right?
> Ah rats. I lost track of that functional change between making the commit
> and writing the changelog.
>
> I'll spin a v2 to rewrite the changelog, and maybe add the "vpid == 0"
> check in a separate patch.
>
What about this:
diff --git a/arch/x86/kvm/vmx/ops.h b/arch/x86/kvm/vmx/ops.h
index eb6adc77a55d..2ab88984b22f 100644
--- a/arch/x86/kvm/vmx/ops.h
+++ b/arch/x86/kvm/vmx/ops.h
@@ -255,13 +255,10 @@ static inline void __invept(unsigned long ext, u64 eptp, gpa_t gpa)
static inline void vpid_sync_context(int vpid)
{
- if (vpid == 0)
- return;
-
- if (cpu_has_vmx_invvpid_single())
- __invvpid(VMX_VPID_EXTENT_SINGLE_CONTEXT, vpid, 0);
- else
+ if (!cpu_has_vmx_invvpid_single())
__invvpid(VMX_VPID_EXTENT_ALL_CONTEXT, 0, 0);
+ else if (vpid != 0)
+ __invvpid(VMX_VPID_EXTENT_SINGLE_CONTEXT, vpid, 0);
}
static inline void vpid_sync_vcpu_addr(int vpid, gva_t addr)
next prev parent reply other threads:[~2020-02-21 17:28 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-02-20 20:43 [PATCH 00/10] KVM: x86: Clean up VMX's TLB flushing code Sean Christopherson
2020-02-20 20:43 ` [PATCH 01/10] KVM: VMX: Use vpid_sync_context() directly when possible Sean Christopherson
2020-02-21 13:17 ` Vitaly Kuznetsov
2020-02-21 15:36 ` Sean Christopherson
2020-02-21 17:26 ` Paolo Bonzini
2020-02-20 20:43 ` [PATCH 02/10] KVM: VMX: Move vpid_sync_vcpu_addr() down a few lines Sean Christopherson
2020-02-21 13:19 ` Vitaly Kuznetsov
2020-02-20 20:43 ` [PATCH 03/10] KVM: VMX: Handle INVVPID fallback logic in vpid_sync_vcpu_addr() Sean Christopherson
2020-02-21 13:26 ` Vitaly Kuznetsov
2020-02-20 20:43 ` [PATCH 04/10] KVM: VMX: Fold vpid_sync_vcpu_{single,global}() into vpid_sync_context() Sean Christopherson
2020-02-21 13:39 ` Vitaly Kuznetsov
2020-02-21 15:32 ` Sean Christopherson
2020-02-21 17:28 ` Paolo Bonzini [this message]
2020-02-20 20:43 ` [PATCH 05/10] KVM: nVMX: Use vpid_sync_vcpu_addr() to emulate INVVPID with address Sean Christopherson
2020-02-21 13:43 ` Vitaly Kuznetsov
2020-02-20 20:43 ` [PATCH 06/10] KVM: x86: Move "flush guest's TLB" logic to separate kvm_x86_ops hook Sean Christopherson
[not found] ` <87tv3krqta.fsf@vitty.brq.redhat.com>
2020-02-21 17:31 ` Paolo Bonzini
2020-02-21 17:32 ` Paolo Bonzini
2020-02-20 20:43 ` [PATCH 07/10] KVM: VMX: Clean up vmx_flush_tlb_gva() Sean Christopherson
2020-02-21 13:54 ` Vitaly Kuznetsov
2020-02-20 20:43 ` [PATCH 08/10] KVM: x86: Drop @invalidate_gpa param from kvm_x86_ops' tlb_flush() Sean Christopherson
2020-02-21 13:56 ` Vitaly Kuznetsov
2020-02-20 20:43 ` [PATCH 09/10] KVM: VMX: Drop @invalidate_gpa from __vmx_flush_tlb() Sean Christopherson
2020-02-20 20:43 ` [PATCH 10/10] KVM: VMX: Fold __vmx_flush_tlb() into vmx_flush_tlb() Sean Christopherson
2020-02-21 13:20 ` [PATCH 00/10] KVM: x86: Clean up VMX's TLB flushing code Paolo Bonzini
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