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From:   Will Deacon <will@kernel.org>
To:     linux-arm-kernel@lists.infradead.org,
        Anshuman Khandual <anshuman.khandual@arm.com>,
        linux-kernel@vger.kernel.org, catalin.marinas@arm.com
Cc:     kernel-team@android.com, Will Deacon <will@kernel.org>,
        Jonathan Corbet <corbet@lwn.net>, suzuki.poulose@arm.com,
        linux-doc@vger.kernel.org, lukas.bulwahn@gmail.com,
        Mark Rutland <mark.rutland@arm.com>, james.morse@arm.com
Subject: Re: [PATCH V4] arm64: errata: Workaround possible Cortex-A715 [ESR|FAR]_ELx corruption
Date:   Fri,  6 Jan 2023 17:50:35 +0000
Message-Id: <167302529636.216647.17992487595898822659.b4-ty@kernel.org>
In-Reply-To: <20230102061651.34745-1-anshuman.khandual@arm.com>
References: <20230102061651.34745-1-anshuman.khandual@arm.com>
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On Mon, 2 Jan 2023 11:46:51 +0530, Anshuman Khandual wrote:
> If a Cortex-A715 cpu sees a page mapping permissions change from executable
> to non-executable, it may corrupt the ESR_ELx and FAR_ELx registers, on the
> next instruction abort caused by permission fault.
> 
> Only user-space does executable to non-executable permission transition via
> mprotect() system call which calls ptep_modify_prot_start() and ptep_modify
> _prot_commit() helpers, while changing the page mapping. The platform code
> can override these helpers via __HAVE_ARCH_PTEP_MODIFY_PROT_TRANSACTION.
> 
> [...]

Applied to arm64 (for-next/fixes), thanks!

[1/1] arm64: errata: Workaround possible Cortex-A715 [ESR|FAR]_ELx corruption
      https://git.kernel.org/arm64/c/5db568e748f6

Cheers,
-- 
Will

https://fixes.arm64.dev
https://next.arm64.dev
https://will.arm64.dev