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Date:   Tue, 24 Mar 2020 11:10:31 -0700
From:   Sean Christopherson <sean.j.christopherson@intel.com>
To:     Paolo Bonzini <pbonzini@redhat.com>
Cc:     Vitaly Kuznetsov <vkuznets@redhat.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Jim Mattson <jmattson@google.com>,
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        Miaohe Lin <linmiaohe@huawei.com>,
        Tom Lendacky <thomas.lendacky@amd.com>
Subject: Re: [PATCH v3 34/37] KVM: nVMX: Don't flush TLB on nested VMX
 transition
Message-ID: <20200324181031.GE5998@linux.intel.com>
References: <20200320212833.3507-1-sean.j.christopherson@intel.com>
 <20200320212833.3507-35-sean.j.christopherson@intel.com>
 <4e2b2b82-278e-72d9-4db3-5047b678049c@redhat.com>
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On Tue, Mar 24, 2020 at 12:20:31PM +0100, Paolo Bonzini wrote:
> On 20/03/20 22:28, Sean Christopherson wrote:
> > Unconditionally skip the TLB flush triggered when reusing a root for a
> > nested transition as nested_vmx_transition_tlb_flush() ensures the TLB
> > is flushed when needed, regardless of whether the MMU can reuse a cached
> > root (or the last root).
> > 
> > Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
> 
> So much for my WARN_ON. :)

Ha, yeah.  The double boolean also makes me nervous, but since there are
only two options, it seemed cleaner overall than a single mask-based param,
a ala EMULTYPE.