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Date:   Mon, 15 Jul 2019 15:53:05 -0700
From:   Andi Kleen <ak@linux.intel.com>
To:     Andy Lutomirski <luto@kernel.org>
Cc:     Dave Hansen <dave.hansen@intel.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Uros Bizjak <ubizjak@gmail.com>,
        LKML <linux-kernel@vger.kernel.org>, X86 ML <x86@kernel.org>
Subject: Re: [RFC PATCH, x86]: Disable CPA cache flush for selfsnoop targets
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> I haven't tested on a real kernel with i915.  Does i915 really hit
> this code path?  Does it happen more than once or twice at boot?

Yes some workloads allocate/free a lot of write combined memory
for graphics objects.

-Andi