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 B9D0FC10F05 for ; Thu, 7 Dec 2023 13:56:09 +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:In-Reply-To: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=/eyEFFU9bt1cNxezGVVcpuhdgAiUIl2orvXbtD3apA4=; b=rI/TJdRc3dtTNT Ztm3gv+QcOY2hWNfTDea9BgMC/ttmo+m71Ygs6wYZTBsH9XjsZ7Pd99xg/W0KilY2qw9b0K+g+mIF fpMmhgiK78otYQ7gsAIlFISyzdcEh0FtXxDiqHNydrv6wBDu+dhorpoHFOBwNA27Z+TlWbFRmgvCX l49rCi9kB6Kzy9PuhbCsBS/d4iJWxpO1dqg+foNdrQkgr26THZU4Hkzg8vCvF/QWdrheZW4kw1JFo Tn9RyvdCWhxBNPX1lrf7kr3qwVwJpJNpGjxau8VuRrBfkJ7KBdU32wQE+GLwMJrzahTqmRKBaPuNr 7EVM7Pv1CpgCN1kumI/g==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1rBEqv-00CxL9-0F; Thu, 07 Dec 2023 13:55:45 +0000 Received: from ams.source.kernel.org ([145.40.68.75]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1rBEqo-00CxFL-1C for linux-arm-kernel@lists.infradead.org; Thu, 07 Dec 2023 13:55:39 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by ams.source.kernel.org (Postfix) with ESMTP id C7AEBB826DA; Thu, 7 Dec 2023 13:55:36 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5CF17C433C8; Thu, 7 Dec 2023 13:55:33 +0000 (UTC) Date: Thu, 7 Dec 2023 13:55:31 +0000 From: Catalin Marinas To: Mark Brown Cc: Joey Gouly , linux-arm-kernel@lists.infradead.org, akpm@linux-foundation.org, aneesh.kumar@linux.ibm.com, dave.hansen@linux.intel.com, maz@kernel.org, oliver.upton@linux.dev, shuah@kernel.org, will@kernel.org, kvmarm@lists.linux.dev, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org, James Morse , Suzuki K Poulose , Zenghui Yu Subject: Re: [PATCH v3 05/25] arm64: context switch POR_EL0 register Message-ID: References: <20231124163510.1835740-1-joey.gouly@arm.com> <20231124163510.1835740-6-joey.gouly@arm.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20231207_055538_556002_D68C4E38 X-CRM114-Status: GOOD ( 10.46 ) 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 Sat, Nov 25, 2023 at 12:02:49PM +0000, Mark Brown wrote: > On Fri, Nov 24, 2023 at 04:34:50PM +0000, Joey Gouly wrote: > > > +static void flush_poe(void) > > +{ > > + if (system_supports_poe()) > > + write_sysreg_s(POR_EL0_INIT, SYS_POR_EL0); > > +} > > Here we have no isb()... My immediate thought was that we'd not care about the ISB here since we'll have an ERET before getting to EL0. However, we may have some LDTR/STTR populating the new process args page on exec which may, in theory, pick up a stale POR_EL0. -- Catalin _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel