linux-kernel - Re: [PATCH v3] arm64: errata: Work around AmpereOne's erratum AC04_CPU

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: <86ecwsgxnh.fsf@scott-ph-mail.amperecomputing.com>
Date: Tue, 13 May 2025 11:42:42 -0700
From: D Scott Phillips <scott@...amperecomputing.com>
To: Oliver Upton <oliver.upton@...ux.dev>
Cc: Catalin Marinas <catalin.marinas@....com>, James Clark
 <james.clark@...aro.org>, James Morse <james.morse@....com>, Joey Gouly
 <joey.gouly@....com>, Kevin Brodsky <kevin.brodsky@....com>, Marc Zyngier
 <maz@...nel.org>, Mark Brown <broonie@...nel.org>, Mark Rutland
 <mark.rutland@....com>, "Rob Herring  (Arm)" <robh@...nel.org>, Shameer
 Kolothum <shameerali.kolothum.thodi@...wei.com>, Shiqi Liu
 <shiqiliu@...t.edu.cn>, Will Deacon <will@...nel.org>, Yicong Yang
 <yangyicong@...ilicon.com>, kvmarm@...ts.linux.dev,
 linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH v3] arm64: errata: Work around AmpereOne's erratum
 AC04_CPU_23

Oliver Upton <oliver.upton@...ux.dev> writes:

> Hey D Scott,
>
> On Thu, May 08, 2025 at 02:00:09PM -0700, D Scott Phillips wrote:
>> On AmpereOne AC04, updates to HCR_EL2 can rarely corrupt simultaneous
>> translations for data addresses initiated by load/store instructions.
>> Only instruction initiated translations are vulnerable, not translations
>> from prefetches for example. A DSB before the store to HCR_EL2 is
>> sufficient to prevent older instructions from hitting the window for
>> corruption, and an ISB after is sufficient to prevent younger
>> instructions from hitting the window for corruption.
>> 
>> Signed-off-by: D Scott Phillips <scott@...amperecomputing.com>
>
> Overall looks good, still needs an entry in Documentation/arch/arm64/silicon-errata.rst
> which Marc noted in v2.

Ah, sorry for missing that and making you repeat yourself. I'll fix
that.