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Date:   Mon, 20 Jul 2020 20:03:19 -0700
From:   Sean Christopherson <sean.j.christopherson@intel.com>
To:     Alex Williamson <alex.williamson@redhat.com>
Cc:     Paolo Bonzini <pbonzini@redhat.com>,
        Vitaly Kuznetsov <vkuznets@redhat.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Jim Mattson <jmattson@google.com>,
        Joerg Roedel <joro@8bytes.org>, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        Xiong Zhang <xiong.y.zhang@intel.com>,
        Wayne Boyer <wayne.boyer@intel.com>,
        Zhenyu Wang <zhenyuw@linux.intel.com>,
        Jun Nakajima <jun.nakajima@intel.com>,
        Weijiang Yang <weijiang.yang@intel.com>
Subject: Re: [PATCH] KVM: x86/mmu: Add capability to zap only sptes for the
 affected memslot
Message-ID: <20200721030319.GD20375@linux.intel.com>
References: <20200703025047.13987-1-sean.j.christopherson@intel.com>
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+Weijiang

On Mon, Jul 13, 2020 at 12:06:50PM -0700, Sean Christopherson wrote:
> The only ideas I have going forward are to:
> 
>   a) Reproduce the bug outside of your environment and find a resource that
>      can go through the painful bisection.

We're trying to reproduce the original issue in the hopes of biesecting, but
have not yet discovered the secret sauce.  A few questions:

  - Are there any known hardware requirements, e.g. specific flavor of GPU?

  - What's the average time to failure when running FurMark/PassMark?  E.g.
    what's a reasonable time to wait before rebooting to rerun the tests (I
    assume this is what you meant when you said you sometimes needed to
    reboot to observe failure).

Thanks!