From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 90AD51E492; Sat, 11 Jan 2025 15:02:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736607758; cv=none; b=Hce9rSVS6RxxxYIGsFEDPFv1PPZvnYfQL/EJCkK/UFJdYZ5F+7rbQm06AnXIJyRWbWGXUpAT3FjLmNhsNhaJOWzb7jUJ1l5bAPrpcp2O+ZHi/ExvEMOwq7M7sxus1cLlI2e8pCvxigQkDe0p6yK1YQzBBUxyzQJzJyQQUBc74uo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736607758; c=relaxed/simple; bh=U6bro49caK6aBzW6XG6V8QOCPxjNZ0rPepiWlKEKqd0=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version:Content-Type; b=WlI0W0nHaHEIGeDyFAPrxFOax5u8b+Lwm0w8Cy0yIBWs+gx5DyffMNHq+OKFk1OnirVdpxRxPdLYJDS4fpRTmvhcn/RNA2uW5IIF/hLdxSmYQytjV5SMXaI2Ff7WofaCWAt9jRdKwzR4fmaHCP5rsCrCd4O3dviMBusBIk6YkOc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=pAxFbrlv; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="pAxFbrlv" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5C313C4CED2; Sat, 11 Jan 2025 15:02:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1736607758; bh=U6bro49caK6aBzW6XG6V8QOCPxjNZ0rPepiWlKEKqd0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pAxFbrlvT1HYG5aLIdA47ajh4hlbVAT+fWIMgcyLXsQM239da7+yQ0KjaOad78SDC a1uYSdK7mXAdYP0jWelWC3fHZAWcYqshrtiMtqagMwb9vmLpSpGIWO3B5+7/SZ3rCf E0xRN6O/0IcTbHN2XDkzU7yA+WTdqFfGqq5ZEzCLzrFCqIZyNxM9X8c/JHQRAoxfhn +tSpngkIwXnPJwoseZQ7eb6AI1OFOLhNUwxqpHtJDyswqmJarqnrmIgrIn3EWpqmih p/muBQthODZyn/ERV8zdLWr7vEJoTN7LIZxZUy4Fy0B8nPWRdtqhR523CMZtXSiWdg Ee14JZGEMVMTA== Received: from sofa.misterjones.org ([185.219.108.64] helo=valley-girl.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.95) (envelope-from ) id 1tWd0W-00BBeb-3P; Sat, 11 Jan 2025 15:02:36 +0000 From: Marc Zyngier To: Oliver Upton , Joey Gouly , Suzuki K Poulose , Zenghui Yu , Catalin Marinas , Will Deacon , "Rob Herring (Arm)" Cc: Mark Rutland , Anshuman Khandual , linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linux-kernel@vger.kernel.org Subject: Re: [PATCH] KVM: arm64: Explicitly handle BRBE traps as UNDEFINED Date: Sat, 11 Jan 2025 15:02:33 +0000 Message-Id: <173660773861.818546.3192188976167687860.b4-ty@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20250109223836.419240-1-robh@kernel.org> References: <20250109223836.419240-1-robh@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: oliver.upton@linux.dev, joey.gouly@arm.com, suzuki.poulose@arm.com, yuzenghui@huawei.com, catalin.marinas@arm.com, will@kernel.org, robh@kernel.org, mark.rutland@arm.com, anshuman.khandual@arm.com, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linux-kernel@vger.kernel.org X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false On Thu, 09 Jan 2025 16:38:36 -0600, Rob Herring (Arm) wrote: > The Branch Record Buffer Extension (BRBE) adds a number of system > registers and instructions which we don't currently intend to expose to > guests. Our existing logic handles this safely, but this could be > improved with some explicit handling of BRBE. > > KVM currently hides BRBE from guests: the cpufeature code's > ftr_id_aa64dfr0[] table doesn't have an entry for the BRBE field, and so > this will be zero in the sanitised value of ID_AA64DFR0 exposed to > guests via read_sanitised_id_aa64dfr0_el1(). > > [...] Applied to next, thanks! [1/1] KVM: arm64: Explicitly handle BRBE traps as UNDEFINED commit: a7f1fa5564be565bd4bc18875bb46ffd0c01d292 Cheers, M. -- Without deviation from the norm, progress is not possible.