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Message-ID: <3e39adad-3b1d-18c0-29d5-e0268c0fa083@intel.com>
Date:   Thu, 30 Jun 2022 07:22:08 -0700
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Subject: Re: [PATCH] x86/fault: ignore RSVD flag in error code if P flag is 0
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To:     Vasily Averin <vvs@openvz.org>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Andy Lutomirski <luto@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        x86@kernel.org, "H. Peter Anvin" <hpa@zytor.com>
Cc:     kernel@openvz.org, linux-kernel@vger.kernel.org,
        Konstantin Khorenko <khorenko@virtuozzo.com>,
        steve.sipes@comandsolutions.com
References: <9bc8de5f-fd80-57fe-0169-0ec942638299@openvz.org>
 <85bd8614-9a55-3113-e5a8-b7e73f636135@openvz.org>
From:   Dave Hansen <dave.hansen@intel.com>
In-Reply-To: <85bd8614-9a55-3113-e5a8-b7e73f636135@openvz.org>
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On 6/29/22 22:58, Vasily Averin wrote:
> Some older Intel CPUs have errata:
> "Not-Present Page Faults May Set the RSVD Flag in the Error Code

Please include a link to the documentation when you cite things like
this.  For example, this is very helpful:

	Several older Intel CPUs have this or a similar erratum.  For
	instance, the "Intel Xeon Processor 5400 Series Specification
	Update" has "AX74 ... Not-Present Page Faults May Set the RSVD
	Flag in the Error Code".

	https://www.intel.com/content/dam/www/public/us/en/documents/specification-updates/xeon-5400-spec-update.pdf

That makes it a *LOT* easier to find the actual erratum and its text.  I
honestly also woudln't mind if you just copy a chunk of the problem text
verbatim into the changelog.  Intel does have a habit of updating text
in documents like that and it's quite handy to have a snapshot of what
you were reading when you wrote the patch.