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 X-Spam-Level: X-Spam-Status: No, score=-5.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id CC1E3C433E0 for ; Tue, 9 Feb 2021 11:56:50 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 4FC6964E7C for ; Tue, 9 Feb 2021 11:56:50 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4FC6964E7C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References:Message-ID: Subject: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=L5WzMaVgO3av7pfBT8lLS6htTjdYFu7UiBCn7Q76EQQ=; b=iN5wrCYwAgM65+rR6Pc2mkbSH DPhdpIcP6YX6uzGVhDlFcq+4M2TZGCqMBNaHsxvrsBMGHFCOWw+FwfK7ahkHJfvt84IAul5gHfeXI rGx6dX4f30TLQLWGhXnJbRM3pybdCfUsRtZxjkQkPl5JRRm5ylf5bwp95Q0CNnsX/T1UmGLzNfzX2 mEmZlddSk3SNH9Ik2H6VncO1pIHTjx5JwvNRwdPesDqb4Q+qqqzuTv6119QNqwgOmmuHHgZV21z7n cMetvOYimfeBpv6HKc5uguvhTPzLkpZMqVO1RXBxuI/Hg8hYwmAQCCB4cnvTpJugmd3RdScuMVRM8 RQxyCgTIA==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1l9RcM-00046C-Qi; Tue, 09 Feb 2021 11:55:42 +0000 Received: from mail.kernel.org ([198.145.29.99]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1l9RcJ-00045f-9Q for linux-arm-kernel@lists.infradead.org; Tue, 09 Feb 2021 11:55:40 +0000 Received: by mail.kernel.org (Postfix) with ESMTPSA id DB61664E3B; Tue, 9 Feb 2021 11:55:35 +0000 (UTC) Date: Tue, 9 Feb 2021 11:55:33 +0000 From: Catalin Marinas To: Vincenzo Frascino Subject: Re: [PATCH v12 6/7] arm64: mte: Save/Restore TFSR_EL1 during suspend Message-ID: <20210209115533.GE1435@arm.com> References: <20210208165617.9977-1-vincenzo.frascino@arm.com> <20210208165617.9977-7-vincenzo.frascino@arm.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20210208165617.9977-7-vincenzo.frascino@arm.com> User-Agent: Mutt/1.10.1 (2018-07-13) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210209_065539_401583_1777F083 X-CRM114-Status: GOOD ( 13.67 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Branislav Rankov , Marco Elver , Lorenzo Pieralisi , Andrey Konovalov , Evgenii Stepanov , linux-kernel@vger.kernel.org, kasan-dev@googlegroups.com, Alexander Potapenko , linux-arm-kernel@lists.infradead.org, Andrey Ryabinin , Andrew Morton , Will Deacon , Dmitry Vyukov 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 Mon, Feb 08, 2021 at 04:56:16PM +0000, Vincenzo Frascino wrote: > When MTE async mode is enabled TFSR_EL1 contains the accumulative > asynchronous tag check faults for EL1 and EL0. > > During the suspend/resume operations the firmware might perform some > operations that could change the state of the register resulting in > a spurious tag check fault report. > > Save/restore the state of the TFSR_EL1 register during the > suspend/resume operations to prevent this to happen. Do we need a similar fix for TFSRE0_EL1? We get away with this if suspend is only entered on the idle (kernel) thread but I recall we could also enter suspend on behalf of a user process (I may be wrong though). If that's the case, it would make more sense to store the TFSR* regs in the thread_struct alongside sctlr_tcf0. If we did that, we'd not need the per-cpu mte_suspend_tfsr_el1 variable. -- Catalin _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel