Re: [PATCH 04/10] arm64: mops: document boot requirements for MOPS
From: Catalin Marinas <catalin.marinas@arm.com>
Date: 2023-03-17 15:09:18
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On Thu, Feb 16, 2023 at 04:00:06PM +0000, Kristina Martsenko wrote:
+ For CPUs with Memory Copy and Memory Set instructions (FEAT_MOPS): + + - If the kernel is entered at EL1 and EL2 is present: + + - HCRX_EL2.MSCEn (bit 11) must be initialised to 0b1. + + - HCRX_EL2.MCE2 (bit 10) must be initialised to 0b0.
Regarding MCE2, does EL1 actually care if EL2 wants to handle all the memcpy/memset exceptions? There may even be a valid case to do this at EL2 if you run a guest that uses these instructions but has no clue on how to deal with the specific exception like WrongOption. -- Catalin _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel