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=-7.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,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 01CF7C04FF3 for ; Mon, 24 May 2021 12:06:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D86346109F for ; Mon, 24 May 2021 12:06:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232880AbhEXMHj (ORCPT ); Mon, 24 May 2021 08:07:39 -0400 Received: from mail.kernel.org ([198.145.29.99]:51020 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232854AbhEXMHY (ORCPT ); Mon, 24 May 2021 08:07:24 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id F01986109F; Mon, 24 May 2021 12:05:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1621857957; bh=85GHMsUoibbHgirlYFFhaTA9Sdo9UthLUckoWESIwSM=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=XIeHN6J3eAWaPP8M5bI46CAlm6nvOZ8WtHjqWctWWSO1XoS9gXf5yeVC5JjUN+lE8 2kxHbyWu1ykUsYJeBgBARKVEM6FNJ8t5cSkn7ner9tRd5QM5y42iM2c0dLhIWaQiyX kc5QTSTedbmkTi9GCcozYmgnXo5s7nh6aVARp4yDbCGgNF4Oz/sntW4xmdVVM2T9PZ ScX86Bs6brKalY5EzbblPAHaY09ykRnG7cSaMOw/pnqNnP9H+8uORVIpc/+gkCJUEx XDQ02xxZ2jSosM+Q9qRpytm6y5Amrf7pPr3ZvD/NodDWFUAyVMUMl2JPiosY4AP+Dr Z9H4lMOfRvvVQ== Date: Mon, 24 May 2021 13:05:50 +0100 From: Will Deacon To: Catalin Marinas Cc: linux-arm-kernel@lists.infradead.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, Marc Zyngier , Greg Kroah-Hartman , Peter Zijlstra , Morten Rasmussen , Qais Yousef , Suren Baghdasaryan , Quentin Perret , Tejun Heo , Li Zefan , Johannes Weiner , Ingo Molnar , Juri Lelli , Vincent Guittot , "Rafael J. Wysocki" , kernel-team@android.com Subject: Re: [PATCH v6 02/21] arm64: Allow mismatched 32-bit EL0 support Message-ID: <20210524120550.GA14913@willie-the-truck> References: <20210518094725.7701-1-will@kernel.org> <20210518094725.7701-3-will@kernel.org> <20210521102523.GB6675@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210521102523.GB6675@arm.com> User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, May 21, 2021 at 11:25:23AM +0100, Catalin Marinas wrote: > On Tue, May 18, 2021 at 10:47:06AM +0100, Will Deacon wrote: > > +static bool has_32bit_el0(const struct arm64_cpu_capabilities *entry, int scope) > > +{ > > + if (!has_cpuid_feature(entry, scope)) > > + return allow_mismatched_32bit_el0; > > + > > + if (scope == SCOPE_SYSTEM) > > + pr_info("detected: 32-bit EL0 Support\n"); > > + > > + return true; > > +} > > We may have discussed this before: AFAICT this will print 32-bit EL0 > detected even if there's no 32-bit EL0 on any CPU. Should we instead > print 32-bit EL0 detected on CPU X when allow_mismatched_32bit_el0 is > passed? It would also give us an indication of the system configuration > when people start reporting bugs. The function above only runs if we've detected 32-bit support via aa64pfr0_el1, so I think we're ok. We also have a print when we detect the mismatch (see enable_mismatched_32bit_el0()). Will 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=-5.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, 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 1242CC04FF3 for ; Mon, 24 May 2021 16:27:15 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id C71A861057 for ; Mon, 24 May 2021 16:27:14 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C71A861057 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org 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=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=/hmzoYZWahrhTwAi6hP4GeIkYDEH5NkCELs3Mz7FCgo=; b=caXvBZ0plwchyS 69WQpZ2bcNGJwQMKKr3fE8pPQQewoipsfDcyM1hrIF2NEuzZ5d5RLxRHdAtGk/pBvD0/KfLosvPpi aqb2BFJMEW4XsFFJL0m82vf5FNw26oYpVv0cjwR5Id5t7M1K2korNbCeqoieNLosgjYYnk2Ouhazs 2gZUKy4iyLnx7+0UGqFRPqTpoWbDIYySiS9hwRFAm0k/ladLdym9bducW7TSNLMq+7Vm4bFpPjHgZ uUxysoYh/8ygKX5gXAsQEpTEKg/q/O0ySEG8u4TD8KLoIpB2a4s/VmF4mpyy0FZ2lhyCsBPpYnDVc FPw7IWVgwkbtyMpVlZ4w==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1llDOP-0015zA-Gw; Mon, 24 May 2021 16:25:26 +0000 Received: from mail.kernel.org ([198.145.29.99]) by bombadil.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1ll9LJ-000tpe-NA for linux-arm-kernel@lists.infradead.org; Mon, 24 May 2021 12:05:58 +0000 Received: by mail.kernel.org (Postfix) with ESMTPSA id F01986109F; Mon, 24 May 2021 12:05:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1621857957; bh=85GHMsUoibbHgirlYFFhaTA9Sdo9UthLUckoWESIwSM=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=XIeHN6J3eAWaPP8M5bI46CAlm6nvOZ8WtHjqWctWWSO1XoS9gXf5yeVC5JjUN+lE8 2kxHbyWu1ykUsYJeBgBARKVEM6FNJ8t5cSkn7ner9tRd5QM5y42iM2c0dLhIWaQiyX kc5QTSTedbmkTi9GCcozYmgnXo5s7nh6aVARp4yDbCGgNF4Oz/sntW4xmdVVM2T9PZ ScX86Bs6brKalY5EzbblPAHaY09ykRnG7cSaMOw/pnqNnP9H+8uORVIpc/+gkCJUEx XDQ02xxZ2jSosM+Q9qRpytm6y5Amrf7pPr3ZvD/NodDWFUAyVMUMl2JPiosY4AP+Dr Z9H4lMOfRvvVQ== Date: Mon, 24 May 2021 13:05:50 +0100 From: Will Deacon To: Catalin Marinas Cc: linux-arm-kernel@lists.infradead.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, Marc Zyngier , Greg Kroah-Hartman , Peter Zijlstra , Morten Rasmussen , Qais Yousef , Suren Baghdasaryan , Quentin Perret , Tejun Heo , Li Zefan , Johannes Weiner , Ingo Molnar , Juri Lelli , Vincent Guittot , "Rafael J. Wysocki" , kernel-team@android.com Subject: Re: [PATCH v6 02/21] arm64: Allow mismatched 32-bit EL0 support Message-ID: <20210524120550.GA14913@willie-the-truck> References: <20210518094725.7701-1-will@kernel.org> <20210518094725.7701-3-will@kernel.org> <20210521102523.GB6675@arm.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20210521102523.GB6675@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-20210524_050557_800042_A8C050B1 X-CRM114-Status: GOOD ( 12.90 ) 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 Fri, May 21, 2021 at 11:25:23AM +0100, Catalin Marinas wrote: > On Tue, May 18, 2021 at 10:47:06AM +0100, Will Deacon wrote: > > +static bool has_32bit_el0(const struct arm64_cpu_capabilities *entry, int scope) > > +{ > > + if (!has_cpuid_feature(entry, scope)) > > + return allow_mismatched_32bit_el0; > > + > > + if (scope == SCOPE_SYSTEM) > > + pr_info("detected: 32-bit EL0 Support\n"); > > + > > + return true; > > +} > > We may have discussed this before: AFAICT this will print 32-bit EL0 > detected even if there's no 32-bit EL0 on any CPU. Should we instead > print 32-bit EL0 detected on CPU X when allow_mismatched_32bit_el0 is > passed? It would also give us an indication of the system configuration > when people start reporting bugs. The function above only runs if we've detected 32-bit support via aa64pfr0_el1, so I think we're ok. We also have a print when we detect the mismatch (see enable_mismatched_32bit_el0()). Will _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel