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From:   Wanpeng Li <kernellwp@gmail.com>
Date:   Fri, 14 Feb 2020 16:59:18 +0800
Message-ID: <CANRm+CwVyRgkG1MEHp25zNrqPoJoV72h7HUz_5n_5GWonj5mwQ@mail.gmail.com>
Subject: Re: [PATCH RESEND] KVM: X86: Grab KVM's srcu lock when accessing hv
 assist page
To:     Paolo Bonzini <pbonzini@redhat.com>
Cc:     LKML <linux-kernel@vger.kernel.org>, kvm <kvm@vger.kernel.org>,
        Sean Christopherson <sean.j.christopherson@intel.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Vitaly Kuznetsov <vkuznets@redhat.com>,
        Jim Mattson <jmattson@google.com>,
        Joerg Roedel <joro@8bytes.org>
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On Fri, 14 Feb 2020 at 16:58, Paolo Bonzini <pbonzini@redhat.com> wrote:
>
> On 14/02/20 09:51, Wanpeng Li wrote:
> > From: Wanpeng Li <wanpengli@tencent.com>
> >
> > Acquire kvm->srcu for the duration of mapping eVMCS to fix a bug where accessing
> > hv assist page derefences ->memslots without holding ->srcu or ->slots_lock.
>
> Perhaps nested_sync_vmcs12_to_shadow should be moved to
> prepare_guest_switch, where the SRCU is already taken.

Will do.

    Wanpeng