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=-8.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham 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 3D7BBC388F7 for ; Wed, 28 Oct 2020 15:15:26 +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 CB97124764 for ; Wed, 28 Oct 2020 15:15:25 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="3EVMV5eM" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CB97124764 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=KyrU8MQlc6A9cuzkyleoeMpBXVT9zJSDh5AMgUTTDlo=; b=3EVMV5eMn7KhYMU8J2rruK7K3 rLoO29o0hUuCuWVjzTrPzi4Ez64be+MkwfnXV0j+LK8xHdFg7xOEhQHeByau+vtLUoXeckkm6SzOt SvHbb+e0oLmhiUZSj+JAUJAiffebpmIPqsrN2DbjRHNNIGnV7Igs+Fr1XxVH45bEWdg2jAIEXXttl dBBJwPE+VCic5JOkmMM/3/5KWjzW37O34/SElheUFKMOiP+FVWWMYXtKpdu8jP9fTx5eydg89BZL9 ZCcuX+pZVWzcepvH8maMzOwqFQu4FDwS7fpK5KNOkZ6MZQSWpqDw5P+i3W4sFbj+kwHy519nc1VD1 bgssOQyVg==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kXnA5-0007uF-64; Wed, 28 Oct 2020 15:14:53 +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 1kXnA0-0007sP-Fo for linux-arm-kernel@lists.infradead.org; Wed, 28 Oct 2020 15:14:50 +0000 Received: from gaia (unknown [95.145.162.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id CDD7324694; Wed, 28 Oct 2020 15:14:45 +0000 (UTC) Date: Wed, 28 Oct 2020 15:14:43 +0000 From: Catalin Marinas To: Will Deacon Subject: Re: [PATCH 5/6] arm64: Advertise CPUs capable of running 32-bit applcations in sysfs Message-ID: <20201028151442.GI13345@gaia> References: <20201027215118.27003-1-will@kernel.org> <20201027215118.27003-6-will@kernel.org> <20201028121506.GG13345@gaia> <20201028122759.GA28091@willie-the-truck> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20201028122759.GA28091@willie-the-truck> 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-20201028_111448_719020_84240D8C X-CRM114-Status: GOOD ( 24.26 ) 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: linux-arch@vger.kernel.org, kernel-team@android.com, Peter Zijlstra , Marc Zyngier , Qais Yousef , Greg Kroah-Hartman , Suren Baghdasaryan , Morten Rasmussen , linux-arm-kernel@lists.infradead.org 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 Wed, Oct 28, 2020 at 12:27:59PM +0000, Will Deacon wrote: > On Wed, Oct 28, 2020 at 12:15:07PM +0000, Catalin Marinas wrote: > > On Tue, Oct 27, 2020 at 09:51:17PM +0000, Will Deacon wrote: > > > diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu > > > index b555df825447..19893fb8e870 100644 > > > --- a/Documentation/ABI/testing/sysfs-devices-system-cpu > > > +++ b/Documentation/ABI/testing/sysfs-devices-system-cpu > > > @@ -472,6 +472,14 @@ Description: AArch64 CPU registers > > > 'identification' directory exposes the CPU ID registers for > > > identifying model and revision of the CPU. > > > > > > +What: /sys/devices/system/cpu/aarch32_el0 > > > > Nitpick: should we call this aarch32_el0_present? It's not exactly > > present as we populate it as CPUs come online but it's closer to this > > mask than to the online one. > > I don't think so, because a CPU could be set in this mask but not in the > present mask, which is hugely confusing it it has "present" in the name! How can it end up here but not in the present mask? We populate present early if they have a corresponding DT entry. > > > +Date: October 2020 > > > +Contact: Linux ARM Kernel Mailing list > > > +Description: Identifies the subset of CPUs in the system that can execute > > > + AArch32 (32-bit ARM) applications. If absent, then all or none > > > + of the CPUs can execute AArch32 applications and execve() will > > > + behave accordingly. > > > > What does "accordingly" mean? Normally, we'd get ENOEXEC but here the > > execve() "succeeds" followed by a SIGKILL if it ends up on the wrong > > CPU. > > No; if the file is absent then execve() behaves as it always has. Ah, I missed the "absent" part and got confused. -- Catalin _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel