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 A9EF0C61DB9 for ; Fri, 28 Aug 2026 06:34:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:CC:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=D7vAngprU3L4H01wFqx0Qe/le8MQbYlT4Gmn4HY2jeE=; b=Hj3w4qcIm/lA9c7I/33oxYoT2K UEr2IVYvrrUkdLpaw7iJus48LWNlDtph2Z0vycdhf0KD6fxxAMBk/5L0o3M3gqdduNc1LfPsYnY08 6rmfbmue6aRIZqDmJyL/t7SxrGpfkjRjtKx/t0kuK8f8kEDzQabnbJEgjew1jdYB5dGxD7M6EVSfJ I+EY6a9XSakVfdTsS99dGSx+GdpjLmrzEEBOJWAgi5iE8C2iySzAXvfRj1A+otIIktIa5Dgj2RxDr qhvz/hRTeECm0lqPPpTXJXI2gL0PZsp+8nOFy3/fZM+jPS+2PrMs2MpgkXzDrgVTGaW1y8iWEcbtY OAJpQiOw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wzqAV-00000005Cpr-39Ra; Fri, 28 Aug 2026 06:34:27 +0000 Received: from mail-westus3azlp170120001.outbound.protection.outlook.com ([2a01:111:f403:c107::1] helo=PH8PR06CU001.outbound.protection.outlook.com) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wzqAS-00000005CpE-1j6o for linux-arm-kernel@lists.infradead.org; Fri, 28 Aug 2026 06:34:26 +0000 ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=f4iaJJiERI5/FvETJlwmB936EVtldwA/gJEbpxLTlXl5XPPrZgBrONsZ0TQH/K0JD6+FuTTpzFjgfcWUAH/uZLjvhjvNQAtu+tUcNszs6njBbzjUVbIaDqfCiNHGonexIvAoDgtfEzUBj2pAik6GIo7NfHGc3YuPaz3rLMImFqj80/mLe6U6q74nLwsokZfuu0/7QS3PLG5Wtrvdn+aVVGAEmsVJBUrlfoqfRm7kl6tCLtDd8v5e6jeuLrTjEKixC0mPHaAE6V0EIR3mVmj1U1GPq6S0C7lsjBGn2NlR4JuRjVJ85bMQ6zoZnkewXC8CWA5DB0UMnZix/AzvG4ik4Q== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector10001; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=D7vAngprU3L4H01wFqx0Qe/le8MQbYlT4Gmn4HY2jeE=; b=zJ7Cb9/+O1MVJbruXaoej2guTcGjt3iYl97+FiwjHYTbjk7HNnWUSKFnxz3tJ0AjIUMNpNLG+JmDjI4oz8jfeiO0QluQHG+jSJusuzJMr+aOTriHVZ1UMZjKsFtgDO7cTlxkQKhwLm7FU6Qar0HWOsYKpnkCHIL9cpgFck1FFk6mkMjFMZdJwX4LlBd5up+jpzfw2RehAMYSexSss9Dejy+TfmN+wk1p8Xl+By2MnLRc9GCg1hzN+QXtXMtyc8ZtW6SnY0tNC6t3vCXYz4NKR8wR1BNJTH/TJichWTaQDlnF34RSeGZ/J02EF4RZCJfvyoN1IdAsNLKBRSHO5vHzew== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass (sender ip is 165.204.84.17) smtp.rcpttodomain=google.com smtp.mailfrom=amd.com; dmarc=pass (p=quarantine sp=quarantine pct=100) action=none header.from=amd.com; dkim=none (message not signed); arc=none (0) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amd.com; s=selector1; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=D7vAngprU3L4H01wFqx0Qe/le8MQbYlT4Gmn4HY2jeE=; b=fn+pOvb6IAvT5BMqIFZ35+HJqE/47ntrtIE7HYJ4rNuDMAhh5xS3w1VYwlP19fJBbMsSxd1e3jnRhDjyRFk0cAnuXLclcD73NuQQCbA1IYxJeUnB7biZmPTIb3QdMsH+G6F5mXWMzFXnKdmvJ9y2lFW/0WBb6X0XMvViONioWL0= Received: from MW4PR04CA0047.namprd04.prod.outlook.com (2603:10b6:303:6a::22) by DM4PR12MB6446.namprd12.prod.outlook.com (2603:10b6:8:be::7) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.21.360.10; Fri, 28 Aug 2026 06:34:10 +0000 Received: from CO1PEPF00012E7E.namprd03.prod.outlook.com (2603:10b6:303:6a:cafe::6b) by MW4PR04CA0047.outlook.office365.com (2603:10b6:303:6a::22) with Microsoft SMTP Server (version=TLS1_3, cipher=TLS_AES_256_GCM_SHA384) id 15.21.360.10 via Frontend Transport; Fri, 28 Aug 2026 06:34:10 +0000 X-MS-Exchange-Authentication-Results: spf=pass (sender IP is 165.204.84.17) smtp.mailfrom=amd.com; dkim=none (message not signed) header.d=none;dmarc=pass action=none header.from=amd.com; Received-SPF: Pass (protection.outlook.com: domain of amd.com designates 165.204.84.17 as permitted sender) receiver=protection.outlook.com; client-ip=165.204.84.17; helo=satlexmb07.amd.com; pr=C Received: from satlexmb07.amd.com (165.204.84.17) by CO1PEPF00012E7E.mail.protection.outlook.com (10.167.249.53) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.21.382.8 via Frontend Transport; Fri, 28 Aug 2026 06:34:10 +0000 Received: from satlexmb07.amd.com (10.181.42.216) by satlexmb07.amd.com (10.181.42.216) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.45; Fri, 28 Aug 2026 01:34:05 -0500 Received: from [10.136.43.157] (10.180.168.240) by satlexmb07.amd.com (10.181.42.216) with Microsoft SMTP Server id 15.2.2562.45 via Frontend Transport; Fri, 28 Aug 2026 01:33:56 -0500 Message-ID: <5e2b4e46-8142-4f51-8d52-66910946ff0a@amd.com> Date: Fri, 28 Aug 2026 12:03:51 +0530 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [RFC 08/10] Set PF_RECLAIMABLE_STACK in various places To: David Stevens , Catalin Marinas , Will Deacon , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , , "H . Peter Anvin" , Andrew Morton , Dave Chinner , Qi Zheng , Roman Gushchin , Muchun Song , Peter Zijlstra , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Valentin Schneider , Uladzislau Rezki , David Hildenbrand , Lorenzo Stoakes , "Liam R . Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Kees Cook , Sebastian Andrzej Siewior , Clark Williams , CC: , , , References: <20260827232948.2520558-1-stevensd@google.com> <20260827232948.2520558-9-stevensd@google.com> Content-Language: en-US From: K Prateek Nayak In-Reply-To: <20260827232948.2520558-9-stevensd@google.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-EOPAttributedMessage: 0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: CO1PEPF00012E7E:EE_|DM4PR12MB6446:EE_ X-MS-Office365-Filtering-Correlation-Id: ff09e39e-49d5-4443-5c3b-08df04ce5e55 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|7416014|376014|82310400026|1800799024|36860700016|23010399003|921020|10067099003|56012099006|11063799006|4143699003|18002099003|22082099003; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:165.204.84.17;CTRY:US;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:satlexmb07.amd.com;PTR:InfoDomainNonexistent;CAT:NONE;SFS:(13230040)(7416014)(376014)(82310400026)(1800799024)(36860700016)(23010399003)(921020)(10067099003)(56012099006)(11063799006)(4143699003)(18002099003)(22082099003);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: /bzQXGIkGDqcDuPC1G2P1h9VV7iiEZiesIogpH3lLIWj9QabAa1h8O1pxrHTg1WjUAx32pWkcCUXkcbYvY5nQ4N7Wmo3yYuPKdO6YL/6p0/RfexFDv1TEifdhW2xrwMXxGtnE4ZBTmlVDSfKwagwpPVFwesJ5IP+2gQ17jUp1pLDrgseTbtDnvQGXb2jBySPbIllIDZf9ov/FaqpMaT1ra8Wx/Qs97ZGQbkPr4yDlmopi14KrlpCgaxrskYaC3GAyBKG6Zrd3wXuthzIZYSi5DEhEohP95ebdTj/PrcRYz+4Ttlfr/ZQpAVQ+IGUE1djtsLHeMzyAnUPN8M9L4bJ784yTebEFKqxNuP1MbYZc2LPse7/3I1Xk+36cfZ6p4W1r5sNoSx/6dSNjU7BJySNN5pKv2JnuQRkS/mUEIJfKquRneDzWSg3M9i0wvyuaplg X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 28 Aug 2026 06:34:10.0970 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: ff09e39e-49d5-4443-5c3b-08df04ce5e55 X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=3dd8961f-e488-4e60-8e11-a82d994e183d;Ip=[165.204.84.17];Helo=[satlexmb07.amd.com] X-MS-Exchange-CrossTenant-AuthSource: CO1PEPF00012E7E.namprd03.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM4PR12MB6446 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260827_233424_456527_09232D5D X-CRM114-Status: GOOD ( 17.06 ) 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: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hello David, On 8/28/2026 4:59 AM, David Stevens wrote: > @@ -469,16 +470,23 @@ anon_pipe_read(struct kiocb *iocb, struct iov_iter *to) > break; > } > mutex_unlock(&pipe->mutex); > - /* > - * We only get here if we didn't actually read anything. > - * > - * But because we didn't read anything, at this point we can > - * just return directly with -ERESTARTSYS if we're interrupted, > - * since we've done any required wakeups and there's no need > - * to mark anything accessed. And we've dropped the lock. > - */ > - if (wait_event_interruptible_exclusive(pipe->rd_wait, pipe_readable(pipe)) < 0) > - return -ERESTARTSYS; > + > + { > + guard(allow_stack_reclaim)(); nit. You can just use a scoped_guard(allow_stack_reclaim) { if (wait_event_interruptible_exclusive(...)) return -ERESTARTSYS; } here. Same comment for rest of the thread where a scoped_guard() can be used instead of this pattern. > + /* > + * We only get here if we didn't actually read > + * anything. > + * > + * But because we didn't read anything, at this point > + * we can just return directly with -ERESTARTSYS if > + * we're interrupted, since we've done any required > + * wakeups and there's no need to mark anything > + * accessed. And we've dropped the lock. > + */ > + if (wait_event_interruptible_exclusive(pipe->rd_wait, > + pipe_readable(pipe)) < 0) > + return -ERESTARTSYS; > + } -- Thanks and Regards, Prateek