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Date:   Mon, 15 Jul 2019 21:46:33 +0200 (CEST)
From:   Thomas Gleixner <tglx@linutronix.de>
To:     Andi Kleen <ak@linux.intel.com>
cc:     Uros Bizjak <ubizjak@gmail.com>, linux-kernel@vger.kernel.org,
        x86@kernel.org, Andrew Lutomirski <luto@kernel.org>
Subject: Re: [RFC PATCH, x86]: Disable CPA cache flush for selfsnoop
 targets
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On Mon, 15 Jul 2019, Andi Kleen wrote:

> > Right, we don't know where the PAT invocation comes from and whether they
> > are safe to omit flushing the cache. The module load code would be one
> > obvious candidate.
> 
> Module load just changes the writable/executable status, right? That shouldn't
> need to flush in any case because it doesn't change the caching attributes.

Ah right. We don't flush when the caching attributes are not changed.

Thanks,

	tglx