From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 49213ECAAD8 for ; Fri, 16 Sep 2022 17:45:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=X4BCIdrUTWLGcwt0Azco2hZ3lMl5+d0+J6q+6d1xAys=; b=VaR3GXEC4jWuPX r6FALhTV053IBP2PWxXc123NtopcL+SLM+XNlk5/kswMc8NMpspcamDj9Yr4hjOYNzv9JEpHsd1bx cHwDtV49ofLt8yv633YvsQWtSe0aXtB/KxTIfHZsLUMNYVui0f2mD3ANjh6qcI2oXdgyDaxJJbfYu Wn1W8SxNbXqNDHm1vPo3DLtFzBxpNcuPWzCfytHeRqmCyCqF+dVB1M6xzE+K1b+JbpHSdorJ6TKgE jXTIlQ6O6qYzwmOnkQJp9QUm8eXThi6HuPXJK87pj61M4jCWIrjJH3P8WoJjeg13pDYh6Or1VOgqb ksMconyCU0AS2PA+RldA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1oZFNy-00FWO5-0e; Fri, 16 Sep 2022 17:44:18 +0000 Received: from dfw.source.kernel.org ([2604:1380:4641:c500::1]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1oZFNu-00FWLp-0M for linux-arm-kernel@lists.infradead.org; Fri, 16 Sep 2022 17:44:15 +0000 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 7BCEB62C7E; Fri, 16 Sep 2022 17:44:11 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D061CC433C1; Fri, 16 Sep 2022 17:44:09 +0000 (UTC) From: Catalin Marinas To: linux-arm-kernel@lists.infradead.org, James Morse Cc: Will Deacon , Suzuki K Poulose Subject: Re: [PATCH 0/3] arm64: errata: remove BF16 HWCAP due to incorrect result on Cortex-A510 Date: Fri, 16 Sep 2022 18:44:07 +0100 Message-Id: <166335021905.1744084.2870652228263520851.b4-ty@arm.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220909165938.3931307-1-james.morse@arm.com> References: <20220909165938.3931307-1-james.morse@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220916_104414_123903_539642BA X-CRM114-Status: GOOD ( 12.61 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, 9 Sep 2022 17:59:35 +0100, James Morse wrote: > Cortex-A510 has an erratum where the BFMMLA or VMMLA instructions might > produce the incorrect result. This only happens if two Cortex-A510 CPUs > are configured by the SoC manafacturer in a particular way to share some > hardware, and are using it at the same time. It isn't possible for linux > to know how the CPUs were configured, so the only option is to disable > the BF16 feature for all Cortex-A510 CPUs. > > [...] Applied to arm64 (for-next/a510-erratum-2658417), thanks! (I updated the last patch following Suzuki's comments) [1/3] arm64: cpufeature: Force HWCAP to be based on the sysreg visible to user-space https://git.kernel.org/arm64/c/237405ebef58 [2/3] arm64: cpufeature: Expose get_arm64_ftr_reg() outside cpufeature.c https://git.kernel.org/arm64/c/445c953e4a84 [3/3] arm64: errata: remove BF16 HWCAP due to incorrect result on Cortex-A510 https://git.kernel.org/arm64/c/1bdb0fbb2e27 -- Catalin _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel