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Date:   Tue, 13 Nov 2018 10:50:51 -0500
From:   Barret Rhoden <brho@google.com>
To:     David Hildenbrand <david@redhat.com>
Cc:     Dan Williams <dan.j.williams@intel.com>,
        Dave Jiang <dave.jiang@intel.com>,
        Ross Zwisler <zwisler@kernel.org>,
        Vishal Verma <vishal.l.verma@intel.com>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Radim =?UTF-8?B?S3LEjW3DocWZ?= <rkrcmar@redhat.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        linux-nvdimm@lists.01.org, linux-kernel@vger.kernel.org,
        "H. Peter Anvin" <hpa@zytor.com>, x86@kernel.org,
        kvm@vger.kernel.org, yu.c.zhang@intel.com, yi.z.zhang@intel.com
Subject: Re: [PATCH 2/2] kvm: Use huge pages for DAX-backed files
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On 2018-11-13 at 10:36 David Hildenbrand <david@redhat.com> wrote:
> > Note that KVM already faulted in the page (or huge page) in the host's
> > page table, and we hold the KVM mmu spinlock (grabbed before checking
> > the mmu seq).  
> 
> I wonder if the KVM mmu spinlock is enough for walking (not KVM
> exclusive) host page tables. Can you elaborate?

I'll update the commit message with the info from Paolo's email (about
kvm_mmu_notifier_invalidate_range_end()).

Thanks,

Barret