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 EF6BBC02192 for ; Wed, 5 Feb 2025 17:04:05 +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:Content-Type:MIME-Version: References:In-Reply-To:Subject:Cc:To:From:Message-ID:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=WNZoc7GQxb0uQelZhdJhTnURKVZ/o5/b1SSRPsXlmcY=; b=OTeKqjqntzkJ8nCSyJf21NcSD6 sf9glNmc8HrGBYWqHFk5MAQUE3ZPeObTjr6R0YyjmyM7j+0HORlj8rvUCqEXeGKGyrE/8DzLh3r+f r4uz0EYIStGEq0v+INrnRe8MxdaAQqEnGkpvHhmU4XAQyWVzXyIGSqS2//qg2fBVjCfqI/hx3QwN6 QghmOEnVWgcBm6BaL8C5TxdDL0DoU4Dcse/SndxChsvEWSE551anh4/Uw11HehXxFRbv/cxnqqeCH +MIMrUyzBayuRljN/FAXF6st2Y/FtbFJdOkQQ1QaBVhUqKKKtk0vExPYJr5upBSNz+zcU5O09IImG 6WIeBhUA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tfiob-000000042yu-08Rb; Wed, 05 Feb 2025 17:03:53 +0000 Received: from dfw.source.kernel.org ([139.178.84.217]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1tfinD-000000042s0-1y5H for linux-arm-kernel@lists.infradead.org; Wed, 05 Feb 2025 17:02:28 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id E06895C6CFD; Wed, 5 Feb 2025 17:01:46 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 57B94C4CED1; Wed, 5 Feb 2025 17:02:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1738774946; bh=5DayLdJidyaaF50WtqZ5UKKOQ7ZjMYF7PpSflEB5fkg=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=iczTJmTvDBh/ih2YjFeeRgo+b4t4JmWyvk0NJnDzS8BbLHKsY/BKGBCKvwrSv5eLJ UKGpTOkICfhL0N5jUICGkKpX7cQZYPBB98jD78MseUqG9t+O+X6H/c2R4jvpNo9qzN 23V12OVEdG8jvESU4aj9l1WkGXeC7TKK3l4f+r80QjJB/2BTOj4hqmeUmHkomnqmDs MzH72Dnd4zpAe8wL3qMahqkEH7QO6jHGD1hqkcOchPJNk395SUHnBvbnrN0Gj/YXHe mKYQTq2hC+cbVzwaQlNfF6shghQgG1FxCPbaAV8doo+2N4SmwkGFJ2pxBHgDJakpKi aMNSLsBS63AZw== Received: from sofa.misterjones.org ([185.219.108.64] helo=goblin-girl.misterjones.org) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.95) (envelope-from ) id 1tfin9-000qho-JN; Wed, 05 Feb 2025 17:02:23 +0000 Date: Wed, 05 Feb 2025 17:02:22 +0000 Message-ID: <86tt98tjdt.wl-maz@kernel.org> From: Marc Zyngier To: Fuad Tabba Cc: kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, oliver.upton@linux.dev, will@kernel.org, joey.gouly@arm.com, suzuki.poulose@arm.com, yuzenghui@huawei.com, catalin.marinas@arm.com, james.morse@arm.com, jingzhangos@google.com, anshuman.khandual@arm.com, shameerali.kolothum.thodi@huawei.com, gshan@redhat.com Subject: Re: [PATCH v1] arm64: head.S: Do not trap access to MPAMSM_EL1 In-Reply-To: <20250205164630.1706058-1-tabba@google.com> References: <20250205164630.1706058-1-tabba@google.com> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI-EPG/1.14.7 (Harue) FLIM-LB/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL-LB/10.8 EasyPG/1.0.0 Emacs/29.4 (aarch64-unknown-linux-gnu) MULE/6.0 (HANACHIRUSATO) MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Content-Type: text/plain; charset=US-ASCII X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: tabba@google.com, kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, oliver.upton@linux.dev, will@kernel.org, joey.gouly@arm.com, suzuki.poulose@arm.com, yuzenghui@huawei.com, catalin.marinas@arm.com, james.morse@arm.com, jingzhangos@google.com, anshuman.khandual@arm.com, shameerali.kolothum.thodi@huawei.com, gshan@redhat.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250205_090227_548400_AFADCAA4 X-CRM114-Status: GOOD ( 12.64 ) 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, 05 Feb 2025 16:46:27 +0000, Fuad Tabba wrote: > > Bit 50 of MPAM2_EL2, EnMPAMSM, traps access to MPAMSM_EL1 when 0, > as per ARM ARM DDI DDI0487L.a, section D24.12.3. Therefore, > ensure it is set to 1 for the host to disable the traps. But what makes use of this register in the kernel? I can't find any trace of it in 6.14-rc1. Thanks, M. -- Without deviation from the norm, progress is not possible.