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 E7C65C02198 for ; Wed, 12 Feb 2025 17:55:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To: Content-Transfer-Encoding:Content-Type:MIME-Version:References:Message-ID: Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=Gbpsai/LhrNPfjSDLQaQK/5b90CAD+pxt6CDRDE9jrY=; b=jZMoFEXlB9vrjp8kiWkL2jSOsV 48dCbSZnkSPHmJ8wtYXlPDUrWCPoQxKv17YRsmXv8kaJNnzikhkodS9Sr+Qb7XTDmR9g+s4ACtWEg 6S3kbIQm+PTKAEq7sncO6E7mHGnwqNGEGYHrz9nDpBjrBfGdlaR2NcEC7PVzt8/ft4oq/REGstE1z oUlzf+gH+3GaIb56SbUaverdxw/aGmuGfOYDcqut3K3CCWSKYsODyqTE6d1DPTlVSl5YpC5dcVSCx nk/fKUH+3LSC+qlTXTqX4gTAHtQVcbNRaJPfjHTX1rpQHtBpjm3gLgujNdACVcp7oNLF33nrwzI0y NvIZKG5g==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tiGxA-00000008Omv-0Kys; Wed, 12 Feb 2025 17:55:16 +0000 Received: from nyc.source.kernel.org ([147.75.193.91]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1tiGuZ-00000008OLu-2gI6 for linux-arm-kernel@lists.infradead.org; Wed, 12 Feb 2025 17:52:36 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by nyc.source.kernel.org (Postfix) with ESMTP id 8002EA40F45; Wed, 12 Feb 2025 17:50:49 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0B181C4CEE2; Wed, 12 Feb 2025 17:52:31 +0000 (UTC) Date: Wed, 12 Feb 2025 17:52:29 +0000 From: Catalin Marinas To: Doug Anderson Cc: James Morse , Will Deacon , Mark Rutland , Roxana Bradescu , Julius Werner , bjorn.andersson@oss.qualcomm.com, Trilok Soni , linux-arm-msm@vger.kernel.org, Florian Fainelli , linux-arm-kernel@lists.infradead.org, Jeffrey Hugo , Scott Bauer , stable@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v4 2/5] arm64: errata: Assume that unknown CPUs _are_ vulnerable to Spectre BHB Message-ID: References: <20250107200715.422172-1-dianders@chromium.org> <20250107120555.v4.2.I2040fa004dafe196243f67ebcc647cbedbb516e6@changeid> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250212_095235_747465_369284E3 X-CRM114-Status: GOOD ( 13.58 ) 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: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Wed, Jan 29, 2025 at 11:14:20AM -0800, Doug Anderson wrote: > On Wed, Jan 29, 2025 at 8:43 AM James Morse wrote: > > Arm have recently updated that table of CPUs > > with extra entries (thanks for picking those up!) - but now that patch can't be easily > > applied to older kernels. > > I suspect making the reporting assuming-vulnerable may make other CPUs come out of the > > wood work too... > > > > Could we avoid changing this unless we really need to? > > Will / Catalin: Do either of you have an opinion here? Is this about whether to report "vulnerable" for unknown CPUs? I think Will suggested this: https://lore.kernel.org/all/20241219175128.GA25477@willie-the-truck/ That said, some patch splitting will help to make review easier. Should such change be back-portable as well? I think so, it's not only for CPUs we'll see in the future. -- Catalin