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 BB617FCC062 for ; Fri, 6 Mar 2026 19:39:55 +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:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:CC:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=V6eXy/hndPDYnIzd3PKHnJ7e/M513SGL5N6TEtGXG/s=; b=P7LNDc1MQ9wtJeYpjrWlts76GD E3b5bEp14MJatwxvQ1nLmVXGi2h3TBN6wM4nOXfzYpILVoZcqS7Hsq1Gyg6SixHUsrxNdyVN0161M j1B2/JeAyIXPSGm22mYG10Hm7PsrJFZq9MQloGGhii4nVprL+vSmAE3kCd/MOEaFvfmXSCQlLRjzM N/4rPq8VcsilsAl5vapDc1BXFtPCthp/0tu4fgAcy+ZbDpFy1wPji+J7bRsj434JScUr2BO4L/pfF lvI4p0Sz2zn+9xGaoJ/6qZdrNKVegU5C6k/cuj9BEOKlKopDw0zAwe3Roz2T6sARNLoXWfKlDYm05 8dJi/GxQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vyb1Z-00000004Pej-35KB; Fri, 06 Mar 2026 19:39:49 +0000 Received: from mail-northcentralusazlp170130007.outbound.protection.outlook.com ([2a01:111:f403:c105::7] helo=CH4PR04CU002.outbound.protection.outlook.com) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vyb1U-00000004Pdz-0IDI for linux-arm-kernel@lists.infradead.org; Fri, 06 Mar 2026 19:39:47 +0000 ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=UmlGxg8NDbNbKpoOisEOjPXtoZ50tqtqMOaAwPHUsBtvqgCVSXRy/5q+Mcgf+VBcI/L8LAWo8Ww7h1Tqo2Al4gUO60h8ddjzgzF7jf66fHL7y7YA2wWpV795ErGQgwvlBXoc/FLq2zuu5TGg57bMT8zjE2AilnlmHngDuYLs5cPf7dFNC12Rpcb3vO6sFOpyVLHR2bWxe+ayw2fskN5fltug6RjlQ0U05hK1NB3k/s6W59ky075GRyXs9ZMpHj86+hzkhGaQaaZAl4KrUnmPogbwmCrLJ6N8PxkjfrsCG76G4hUvjzcvYWdkpOPkuJpu2tP5c6A2tAj5yDQJ5BnnlQ== 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=V6eXy/hndPDYnIzd3PKHnJ7e/M513SGL5N6TEtGXG/s=; b=HJhwoGNHjuAXnYKJMvE++9NoxuJQdr2E9WE6cE+uxiS5gdRZHN1rPXRv4vNLmRrAVQilU+VCYMXp0ZBGGLVubRekLzIbKPlcN0oXxXUySlNLEKlfAQIWHp+4oA6vCdioTlM+C4aPU61bpjswRGRhSTaE1OJE4PG8QY/k8EKvp+/AsSbQprs4WKQbvA1TPMw9L7AX+4l4tBBl5fexJYUzljcObRZjdPZ0PAf99z9eBrqUUg+z9tLKxF8RdL/v/oM8Atgi5wvrd60MYcV3j3t5u8byIYf0BFml4BzDJpVFNDQIwEDfBYzyoui+k2/zDvT5t9sgxuvJzReFpPE8qwkzcw== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass (sender ip is 216.228.117.160) smtp.rcpttodomain=vger.kernel.org smtp.mailfrom=nvidia.com; dmarc=pass (p=reject sp=reject pct=100) action=none header.from=nvidia.com; dkim=none (message not signed); arc=none (0) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=Nvidia.com; s=selector2; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=V6eXy/hndPDYnIzd3PKHnJ7e/M513SGL5N6TEtGXG/s=; b=QsFtPdMW+zZG/hlF6nMxjMNiH90jOS5zdUS8anRC7U8fo8ItvnpO2i9jxk6jS2LNKGhzfR7If7Zf18g7jnAee1XhBzgDzatXRctqk+Kd1ioAZu0JgGEu6GTXen4UThhqiN48p8O85FjyEFyVa/wD+Sv21MLzm45yueNYPfcUYc3PAJ3EftdI5dcvvh0EJJOeT70o4FqsilqWcUsXlqgtVe2c+4I26Pl8IfZJhp1Lazb5Vj1wgPD+izL25pzQqo87YuPLSgVYjSSgx4+CAIuxeRFxUQrES3CvXtzYtAHA+x87G32kRqF2zYgmEd2TGNYdmg97BoKwkFiVFLH+1HtGOQ== Received: from PH8PR02CA0037.namprd02.prod.outlook.com (2603:10b6:510:2da::35) by LV9PR12MB9757.namprd12.prod.outlook.com (2603:10b6:408:2ed::7) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9678.18; Fri, 6 Mar 2026 19:39:36 +0000 Received: from SJ1PEPF000023DA.namprd21.prod.outlook.com (2603:10b6:510:2da:cafe::53) by PH8PR02CA0037.outlook.office365.com (2603:10b6:510:2da::35) with Microsoft SMTP Server (version=TLS1_3, cipher=TLS_AES_256_GCM_SHA384) id 15.20.9678.19 via Frontend Transport; Fri, 6 Mar 2026 19:39:35 +0000 X-MS-Exchange-Authentication-Results: spf=pass (sender IP is 216.228.117.160) smtp.mailfrom=nvidia.com; dkim=none (message not signed) header.d=none;dmarc=pass action=none header.from=nvidia.com; Received-SPF: Pass (protection.outlook.com: domain of nvidia.com designates 216.228.117.160 as permitted sender) receiver=protection.outlook.com; client-ip=216.228.117.160; helo=mail.nvidia.com; pr=C Received: from mail.nvidia.com (216.228.117.160) by SJ1PEPF000023DA.mail.protection.outlook.com (10.167.244.75) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9700.0 via Frontend Transport; Fri, 6 Mar 2026 19:39:34 +0000 Received: from rnnvmail202.nvidia.com (10.129.68.7) by mail.nvidia.com (10.129.200.66) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.20; Fri, 6 Mar 2026 11:39:12 -0800 Received: from rnnvmail204.nvidia.com (10.129.68.6) by rnnvmail202.nvidia.com (10.129.68.7) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.20; Fri, 6 Mar 2026 11:39:12 -0800 Received: from Asurada-Nvidia (10.127.8.10) by mail.nvidia.com (10.129.68.6) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.20 via Frontend Transport; Fri, 6 Mar 2026 11:39:11 -0800 Date: Fri, 6 Mar 2026 11:39:09 -0800 From: Nicolin Chen To: Jason Gunthorpe CC: , , , , , , , , , , , , , , , , , , Subject: Re: [PATCH v1 2/2] iommu/arm-smmu-v3: Recover ATC invalidate timeouts Message-ID: References: <20260305153911.GT972761@nvidia.com> <20260305234158.GB1651202@nvidia.com> <20260306013347.GD1651202@nvidia.com> <20260306130202.GG1651202@nvidia.com> <20260306192211.GK1651202@nvidia.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <20260306192211.GK1651202@nvidia.com> X-NV-OnPremToCloud: ExternallySecured X-EOPAttributedMessage: 0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: SJ1PEPF000023DA:EE_|LV9PR12MB9757:EE_ X-MS-Office365-Filtering-Correlation-Id: 8157cb26-a924-46bc-b69a-08de7bb818a3 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|82310400026|1800799024|7416014|376014|36860700016; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:216.228.117.160;CTRY:US;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:mail.nvidia.com;PTR:dc6edge1.nvidia.com;CAT:NONE;SFS:(13230040)(82310400026)(1800799024)(7416014)(376014)(36860700016);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: Ebmwti4MccIF0avEtdMzqD7QNbeRQoXj+8JOSU/Wl9dnmioHh8BF/RxXhVxxadfbc0cYHrl5ovKtQ5W+8QBLk/tw9pjywnjbIfkR+K1wtyM0Xh+qvDpSfu/i9gy6WW4QvbFNNojmuf/aRW6Vimo5PpipvsoDAEF6HAoCRkIqblA2yYPha8OtThbx0PpxRtcYF3U84MNpqMLkvIzd90ypHyLtbIeuPYbs3cvbHQXVzyKA3usqDcpANTOaF9CgAWnDMSGQ1Oi/fT2chVDl4tpWfxaqZyewsz1aj8kHCLuYDN9+sbdfgq+YOrpmpmJ1S7dZ1z51Iu/3lsFgJyRhRmYKYOSHNAgjPQTLUtEoyd7sJRVNkf65euH7rmm6TrIueta0rjG+KbWN2yHlB5o2dHb+4YZ+qhVOORWC+vUJKp5qFa0D5R6i2Q26XC9zp8ze8Sz0 X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 06 Mar 2026 19:39:34.9441 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 8157cb26-a924-46bc-b69a-08de7bb818a3 X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=43083d15-7273-40c1-b7db-39efd9ccc17a;Ip=[216.228.117.160];Helo=[mail.nvidia.com] X-MS-Exchange-CrossTenant-AuthSource: SJ1PEPF000023DA.namprd21.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: LV9PR12MB9757 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260306_113944_140420_9318F465 X-CRM114-Status: UNSURE ( 9.68 ) 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: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, Mar 06, 2026 at 03:22:11PM -0400, Jason Gunthorpe wrote: > On Fri, Mar 06, 2026 at 11:20:35AM -0800, Nicolin Chen wrote: > > > In general, the maximum users count of an INV_TYPE_ATS would be 1. > > So, an unref() would be sufficient to mute it, though it'd require > > the unref() API to support a mismatched users counter, because the > > PCI reset in the WQ would block ATS, which would try to unref the > > removed command once again. > > INV_TYPE_ATS_DISABLED could be made to work too.. Overriding the type.. hmm, that's brilliant. Rechecking the unref API, I realized that even the "users" in the latest version isn't atomic anymore. I recall that we are fine to do READ_ONCE/WRITE_ONCE on an int type because invalidation array is serialized by the asid mutex, which wouldn't work either in an ISR or just in the arm_smmu_master/domain_atc_inv()? Thanks Nicolin