linux-kernel - Re: [RESEND PATCH] Make Fujitsu Erratum 010001 patch can be applied on A64FX v1r0

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <20190319125258.GD59586@arrakis.emea.arm.com>
Date:   Tue, 19 Mar 2019 12:52:58 +0000
From:   Catalin Marinas <catalin.marinas@....com>
To:     Mark Rutland <mark.rutland@....com>
Cc:     "Zhang, Lei" <zhang.lei@...fujitsu.com>,
        "Okamoto, Takayuki" <tokamoto@...fujitsu.com>,
        Will Deacon <will.deacon@....com>,
        James Morse <james.morse@....com>,
        linux-kernel@...r.kernel.org, linux-arm-kernel@...ts.infradead.org
Subject: Re: [RESEND PATCH] Make Fujitsu Erratum 010001 patch can be applied
 on A64FX v1r0

On Mon, Mar 18, 2019 at 12:06:06PM +0000, Mark Rutland wrote:
> From 6439e9c0b1525e9d4c7be65552e6f2b1f9d1dbe0 Mon Sep 17 00:00:00 2001
> From: "Okamoto, Takayuki" <tokamoto@...fujitsu.com>
> Date: Fri, 15 Mar 2019 12:22:36 +0000
> Subject: [PATCH] arm64: apply workaround on A64FX v1r0
> 
> Fujitsu erratum 010001 applies to A64FX v0r0 and v1r0, and we try to
> handle either by masking MIDR with MIDR_FUJITSU_ERRATUM_010001_MASK
> before comparing it to MIDR_FUJITSU_ERRATUM_010001.
> 
> Unfortunately, MIDR_FUJITSU_ERRATUM_010001 is constructed incorrectly
> using MIDR_VARIANT(), which is intended to extract the variant field
> from MIDR_EL1, rather than generate the field in-place. This results in
> MIDR_FUJITSU_ERRATUM_010001 being all-ones, and we only match A64FX
> v0r0.
> 
> This patch uses MIDR_CPU_VAR_REV() to generate an in-place mask for the
> variant field, ensuring the we match both v0r0 and v1r0.
> 
> Fixes: 3e32131abc311a5c ("arm64: Add workaround for Fujitsu A64FX erratum 010001")
> Signed-off-by: Zhang Lei <zhang.lei@...fujitsu.com>
> [Mark: use MIDR_CPU_VAR_REV(), reword commit message]
> Signed-off-by: Mark Rutland <mark.rutland@....com>

Thanks. Mark's variant queued for 5.1-rc2.

-- 
Catalin