From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 70A143EFFAF; Thu, 3 Sep 2026 17:00:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788454812; cv=none; b=YZ6/WM56Qwyfp7piDOi/OHTwn+1SpaqvVh116Ft3uGtWzv5jCYg8BR0wcU8NNegdPSA2E2MoT8/ccXz9fUFMwzbmdUg21TvfIHNemc2ds/H8/ScXLZQSLpyol34/3vTgwGIjEj6tayKXBpiMob8/INA1fz147sMpEpSCnZRxyXM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788454812; c=relaxed/simple; bh=KshVxQXNgngisR5BoyKqFhcuY21vSQ6BbLNU5td7rrU=; h=From:Subject:To:Cc:In-Reply-To:References:Content-Type:Date: Message-Id; b=otWv2RRqbtzVWmkK1rHUHFOfM5a54Ps+baNjCTKBLatJvr+jwXPs0IN9BEAZMMIbezgvwLfW3S+QWjAi6YhRSBvPXRwgNRRB42RHWVdC2tYe9H3DQ1LZpE7eVYnziKpRLfxGGcf5CKTezGCgzWih23rFzfHbBvvbTS/3on0xcgY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=K05zf1uA; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="K05zf1uA" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1025F1F000E9; Thu, 3 Sep 2026 17:00:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788454811; bh=zF/KsxokTC2tP5qztmGEE+raUNsT9p6WYChqmGs5mnA=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=K05zf1uAFaRGMCzEKr0GFm+///4YmOKlUvwjN09JnCmFpkoBj6a97KjxUR0y4nMGw LPUGjHFjvIA0l6vu1CE4alhgGVd1A2//T8ANmOvWvywg4YHjvJ9pFmA47mf0rFsvkT bIR5HlplDdSnoy1/2IsZdIpVEuzuQPORjMtsmbfBQun/4APsUkVtr5YzySznx3aeXV Q8sTJx1WY2361yXhCgy2AXyFzaZyohU8WE68wv+euMW6YG32Ix6xAYXSxiqJJOaoXb PpQQ89misAkO7ifQWSUmFK/CmczU0U8FMVzvet5OGtXSGb8rQCg2OPmRaCs1tOOvcQ Oc+B0jEUdYYGw== From: sashiko-bot@kernel.org Subject: Re: [RFC PATCH v7 24/28] arm64: errata: Don't enable guest buffer if misprogrammed Reply-To: sashiko-reviews@lists.linux.dev To: "Alexandru Elisei" Cc: kvmarm@lists.linux.dev, linux-perf-users@vger.kernel.org, "Marc Zyngier" , "Oliver Upton" In-Reply-To: <20260903160623.315525-25-alexandru.elisei@arm.com> References: <20260903160623.315525-1-alexandru.elisei@arm.com> <20260903160623.315525-25-alexandru.elisei@arm.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Thu, 03 Sep 2026 17:00:10 +0000 Message-Id: <20260903170011.1025F1F000E9@smtp.kernel.org> Precedence: bulk X-Mailing-List: linux-perf-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: > When PMBPTR_EL1 is programmed to be equal to or greater than > PMBLIMITR_EL1.Limit, SPE is enabled and PMBSR_EL1.S is zero, the CPU might > deadlock. >=20 > This doesn't affect correctly written software, like the SPE driver, but a > buggy KVM guest might trigger the erratum. The workaround for KVM is not = to > enable the hardware buffer, and, as a consequence, profiling. According > to ARM DDI0487M.c, rule R_PGGHS, this is one of the acceptable > behaviours when the buffer is misprogrammed. >=20 > Several parts are affected: >=20 > * ARM Neoverse-N1 (MP050), SDEN v35, erratum 1978083 > https://support.arm.com/documentation/SDEN-885747/35-0 > * ARM Neoverse-V1 (MP076), SDEN v23, erratum 1978082 > https://support.arm.com/documentation/SDEN-1401781/23-0 > * ARM Cortex-X1 (MP077), SDEN v25, erratum 2004055 > https://support.arm.com/documentation/SDEN-1401782/25-0 > * ARM Cortex-X1C (MP136), SDEN v20, erratum 2004056 > https://support.arm.com/documentation/SDEN-1707914/20-0 > * ARM Cortex-A78 (MP102), SDEN v25, erratum 2004055 > https://support.arm.com/documentation/SDEN-1401784/25-0 > * ARM Cortex-A78AE (MP105), SDEN v22, erratum 2004059 > https://support.arm.com/documentation/SDEN-1707912/22-0 > * ARM Cortex-A78C (MP138), SDEN v20, erratum 2004056 > https://support.arm.com/documentation/SDEN-1707916/20-0 >=20 > Signed-off-by: Alexandru Elisei Sashiko has reviewed this patch and found no issues. It looks great! --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20260903160623.3155= 25-1-alexandru.elisei@arm.com?part=3D24