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=-5.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, NICE_REPLY_A,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 79859C433B4 for ; Thu, 8 Apr 2021 15:25:38 +0000 (UTC) Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (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 1902C610FB for ; Thu, 8 Apr 2021 15:25:38 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1902C610FB 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=desiato.20200630; h=Sender:Content-Transfer-Encoding :Content-Type:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:Date:Message-ID:From: References:Cc:To:Subject:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=pR7SQIQDYQhSg8m2CKi2kgNDTOcm5v6Nj0o0F17Pzik=; b=PKW21/2puSmn2JFYXYvOBP81l EUq8GLju9bXF5rRJKmN3i7dBD6rbADBLxVF9ZYWlE49h6h5/bulFLa2uHvqXLyKSmpesqK/JMZxV8 JTCRB0B1DxxHf1qCrpf3nkIfCoYa4cXuhWgDQdp80nMAoRR14k2yQrN2H3aJcewBRjfYeWPpQPoia RTnSaRI+Hon0sb/KGxerc/zJxXZrIjx8KXkMkH6NEOczeTcOBy+ujlhn0Ij1s6jB2As+lBAzDUSE/ hwvzW9ywu4etzVKE/SkGf6lc5elYnqkkCXZU7NxnQ/5XfhFeRB8Epac3IlgY4N68Xm4Y4R+xTo3U9 5isIZp0Yw==; Received: from localhost ([::1] helo=desiato.infradead.org) by desiato.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1lUWVS-008NDJ-L4; Thu, 08 Apr 2021 15:23:42 +0000 Received: from foss.arm.com ([217.140.110.172]) by desiato.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1lUWVO-008NCF-1y for linux-arm-kernel@lists.infradead.org; Thu, 08 Apr 2021 15:23:39 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id DF131D6E; Thu, 8 Apr 2021 08:23:29 -0700 (PDT) Received: from [10.37.8.4] (unknown [10.37.8.4]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id EE3CB3F694; Thu, 8 Apr 2021 08:23:28 -0700 (PDT) Subject: Re: [PATCH] arm64: mte: Move MTE TCF0 check in entry-common To: Mark Rutland , Will Deacon Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, kasan-dev@googlegroups.com, Catalin Marinas References: <20210408143723.13024-1-vincenzo.frascino@arm.com> <20210408145604.GB18211@willie-the-truck> <20210408150612.GA37165@C02TD0UTHF1T.local> From: Vincenzo Frascino Message-ID: Date: Thu, 8 Apr 2021 16:23:27 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20210408150612.GA37165@C02TD0UTHF1T.local> Content-Language: en-US X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210408_162338_324356_EA3D40A5 X-CRM114-Status: UNSURE ( 9.40 ) X-CRM114-Notice: Please train this message. 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 4/8/21 4:06 PM, Mark Rutland wrote: > On Thu, Apr 08, 2021 at 03:56:04PM +0100, Will Deacon wrote: >> On Thu, Apr 08, 2021 at 03:37:23PM +0100, Vincenzo Frascino wrote: >>> The check_mte_async_tcf macro sets the TIF flag non-atomically. This can >>> race with another CPU doing a set_tsk_thread_flag() and the flag can be >>> lost in the process. >> >> Actually, it's all the *other* flags that get lost! >> You are right, I need to explain this better. ... -- Regards, Vincenzo _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel