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Date: Thu, 22 Aug 2024 12:31:55 +0100
From: Catalin Marinas <catalin.marinas@arm.com>
To: Mark Brown <broonie@kernel.org>
Cc: Will Deacon <will@kernel.org>, Jonathan Corbet <corbet@lwn.net>,
	Andrew Morton <akpm@linux-foundation.org>,
	Marc Zyngier <maz@kernel.org>,
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	Eric Biederman <ebiederm@xmission.com>,
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Subject: Re: [PATCH v11 18/39] arm64/traps: Handle GCS exceptions
Message-ID: <Zschq9JbvIRjmXVR@arm.com>
References: <20240822-arm64-gcs-v11-0-41b81947ecb5@kernel.org>
 <20240822-arm64-gcs-v11-18-41b81947ecb5@kernel.org>
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In-Reply-To: <20240822-arm64-gcs-v11-18-41b81947ecb5@kernel.org>

On Thu, Aug 22, 2024 at 02:15:21AM +0100, Mark Brown wrote:
> A new exception code is defined for GCS specific faults other than
> standard load/store faults, for example GCS token validation failures,
> add handling for this. These faults are reported to userspace as
> segfaults with code SEGV_CPERR (protection error), mirroring the
> reporting for x86 shadow stack errors.
> 
> GCS faults due to memory load/store operations generate data aborts with
> a flag set, these will be handled separately as part of the data abort
> handling.
> 
> Since we do not currently enable GCS for EL1 we should not get any faults
> there but while we're at it we wire things up there, treating any GCS
> fault as fatal.
> 
> Reviewed-by: Thiago Jung Bauermann <thiago.bauermann@linaro.org>
> Signed-off-by: Mark Brown <broonie@kernel.org>

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>