From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=pass header.oldest-pass=0 smtp.remote-ip=40.93.201.13 ARC-Seal: i=2; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=pass; t=1793078859; b=YaqTrXS6Lu384en+w0L3U6wW5pn0w31f42I5VtvUOt70o5ZoPuBYtvvIJ7MiCOU3SK4u vxKvgcQPypd6y8qmbNMwAteF2YuspkhgX6dmjQl1XArIiKRBDAGOGuMW4i8H2R4f11BWQ YYCoDsHakFJWlfi/e6IrZH4xoRkTH4w7BgYsBQVQAQf3j9aj792ShQghbEUn/gh/f92Eo EjQg8EpfWkbm7YJyPSac3BtoMkSNpZQdT2LKCOVGcBdh+qXQvpS4qIK8K4VtDG1vlQsHl uCLkOUsCAy6Wqrc+1Fw1qvehZpmrkWiHaAUvZttdAY+EsmAWDEm1L/LQh65L3oB8RGg== ARC-Message-Signature: i=2; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793078859; h=DMARC-Filter:DKIM-Signature:Received:Received: X-MS-Exchange-Authentication-Results:Received-SPF:Received:Received: Received:Message-ID:Date:MIME-Version:User-Agent:Subject:To:CC: References:Content-Language:From:In-Reply-To:Content-Type: Content-Transfer-Encoding:X-EOPAttributedMessage: X-MS-PublicTrafficType:X-MS-TrafficTypeDiagnostic: X-MS-Office365-Filtering-Correlation-Id:X-MS-Exchange-SenderADCheck: X-MS-Exchange-AntiSpam-Relay:X-Microsoft-Antispam: X-Microsoft-Antispam-Message-Info:X-Forefront-Antispam-Report: X-MS-Exchange-AntiSpam-MessageData-ChunkCount: X-MS-Exchange-AntiSpam-MessageData-0:X-OriginatorOrg: X-MS-Exchange-CrossTenant-OriginalArrivalTime: X-MS-Exchange-CrossTenant-Network-Message-Id: X-MS-Exchange-CrossTenant-Id: X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: X-MS-Exchange-CrossTenant-AuthSource:X-MS-Exchange-CrossTenant-AuthAs: X-MS-Exchange-CrossTenant-FromEntityHeader: X-MS-Exchange-Transport-CrossTenantHeadersStamped; bh=Tf2PWZY1fKwgg5B7a9yjZqdkktnSO5wV2PBaYvFNA9A=; b=Spd9OfsN0NeC4U1AjHWAK6u6dz5H0zAg5FBaIb5SsdvoVBJzqmq2fgnoAEQPlgMFAQ6a E1glaARm+xFS8tlc89hN9Z/Hv0CPy2ie2LJ2RPgCJwUv6gTlGqDKPKDbbgxkgLa2QHQkU aDfCgJe21P+0e/LzLxMRu2AfoOz/jw0G/01uc8ZlXfbU2v5RGkjN/HlQvThkGDPsh+VXE 3WOTbOBYWvcfyigrZ9PbrK0HIoNJBWEnZlp6nQjnepX229SFW/Eoys0Dh9Qs5oqVt6OK6 Ck/xL3+v+slPHTKlqyE4pbsFOdkGMgYhqdUSiZjRscelzUI8F+gUu41SPT62p+6mnWw== ARC-Authentication-Results: i=2; smtp.subspace.kernel.org; dmarc=pass header.from=amd.com; spf=fail smtp.mailfrom=amd.com; dkim=pass header.d=amd.com header.i=@amd.com header.a=rsa-sha256 header.s=selector1 header.b=mhun5C5p; arc=pass header.oldest-pass=0 smtp.remote-ip=40.93.201.13 Received: from CY3PR05CU001.outbound.protection.outlook.com (mail-westcentralusazon11013013.outbound.protection.outlook.com [40.93.201.13]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (secp384r1) server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 90ACA606A31A; Tue, 27 Oct 2026 05:27:38 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 90ACA606A31A Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=amd.com Authentication-Results: smtp.subspace.kernel.org; spf=fail smtp.mailfrom=amd.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=amd.com header.i=@amd.com header.a=rsa-sha256 header.s=selector1 header.b=mhun5C5p ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=JSvyM0mJXk90RMr5x/O4O+hWFPvtOkgteQUfH/qqGvCESqVBUoU77ZLMmcSLHLeKa5klWkdOAYjk+QQq0//+hRwzdbfPlqDuGe+J/tuKnYsoDtV4V51fPCW34lOvgc5jdlrPNSBhpSkPibgM6CVbIsHscC0MVqr8i7y+yQwcTAwrnVv3Xqge/wiLAJyrFxNyo2IcEAzcS5qckb05jDr35wCrHYSR+Y93auc8sJmUaiMY1r8NqKpvdsYhHylLWBxJcRGMH4zoLTLn3+MGi2yJ3MEdQIkfs0bV3dhlOZnAb6dxHQyItJ0KJr/FUk/wKpNFA37V8F8Ix2Rhh20EygHOtw== 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=Tf2PWZY1fKwgg5B7a9yjZqdkktnSO5wV2PBaYvFNA9A=; b=oCz9hkPWtV24/VfdL2KfC3nyoiV/weFSrgPXNE4b9voNwC3DFCYNEtxrWkxbFjVPoHzFpvKv9XGqNbeptu3M8dQ+5+ConTmtgCN2InELaZPCCO6D8AppK/koB8mcClg1cpI+IjlvXa+fNowDzshrUr1G1AI3OemTs0dNBhA9N3K9fstr/vYbKbfwVYKhWj2YB/fuXplbKM7OIYRdPok8fA4FLqaZt/nH9r9rCZhdVriYQJDSPvsWKCQn0xNVbXGl/i81wYnySXJ6ijCZwLHvekm8YRGT9JSDBTPFXe91FsZ45RNsWblkyC++JJjhqCGBFkBkNc8HbkfnylvfRSe07w== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass (sender ip is 165.204.84.17) smtp.rcpttodomain=gmail.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=Tf2PWZY1fKwgg5B7a9yjZqdkktnSO5wV2PBaYvFNA9A=; b=mhun5C5pHV89iQdnxX7yXQn3w6hzq8zGs6p1uigmFsmbJeah+GoD7l1yG252DA6gH9XF0WtBdYSrrJPOC+NANeXOPmdwWNs0VcBqLtb5HMCdprqmi+ONFSwE6PziShp4VT61YOa8FOS5Q/8mMsZKtFUdtDt1QfqvqMvVR9/YBC8= Received: from DS0PR17CA0016.namprd17.prod.outlook.com (2603:10b6:8:191::7) by PH8PR12MB8605.namprd12.prod.outlook.com (2603:10b6:510:1cc::6) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.21.546.22; Tue, 27 Oct 2026 05:23:30 +0000 Received: from CY7PEPF000000ED.namprd04.prod.outlook.com (2603:10b6:8:191:cafe::2d) by DS0PR17CA0016.outlook.office365.com (2603:10b6:8:191::7) with Microsoft SMTP Server (version=TLS1_3, cipher=TLS_AES_256_GCM_SHA384) id 15.21.472.20 via Frontend Transport; Tue, 27 Oct 2026 05:23:30 +0000 X-MS-Exchange-Authentication-Results: mx.microsoft.com 1; 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=satlexmb08.amd.com; pr=C Received: from satlexmb08.amd.com (165.204.84.17) by CY7PEPF000000ED.mail.protection.outlook.com (10.167.247.169) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.21.569.4 via Frontend Transport; Tue, 27 Oct 2026 05:23:29 +0000 Received: from satlexmb07.amd.com (10.181.42.216) by satlexmb08.amd.com (10.181.42.217) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.53; Tue, 27 Oct 2026 00:23:28 -0500 Received: from [10.136.37.101] (10.180.168.240) by satlexmb07.amd.com (10.181.42.216) with Microsoft SMTP Server id 15.2.2562.53 via Frontend Transport; Tue, 27 Oct 2026 00:23:23 -0500 Message-ID: Date: Tue, 27 Oct 2026 10:53:22 +0530 X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: perf/amd/ibs: [BUG?] ibs_op sampling silently stops on Zen3: MSR_AMD64_IBSOPCTL latched, no NMI delivered To: Liew Rui Yan CC: , , , Peter Zijlstra , Manali Shukla , Jim Mattson , Ingo Molnar , Arnaldo Carvalho de Melo , Namhyung Kim , Mark Rutland , "Alexander Shishkin" , Jiri Olsa , Ian Rogers , Adrian Hunter , James Clark , Thomas Gleixner , Borislav Petkov , Dave Hansen , "H. Peter Anvin" , Ravi Bangoria References: <20261019212028.119312-1-aethernet65535@gmail.com> Content-Language: en-US From: Ravi Bangoria In-Reply-To: <20261019212028.119312-1-aethernet65535@gmail.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-EOPAttributedMessage: 0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: CY7PEPF000000ED:EE_|PH8PR12MB8605:EE_ X-MS-Office365-Filtering-Correlation-Id: 76aad62b-c112-49c4-2fe4-08df33ea6f7c X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|7416014|376014|23010399003|36860700016|1800799024|82310400026|261022105027099003|261021121427099003|261022075727099003|3023799007|10067099003|56012099006|22082099003|18002099003|13003099007|11063799006|261026140227099003; X-Microsoft-Antispam-Message-Info: OH0ij9HPFKsF0eK2lQuwSfiqQ/oPAfYy3JRdCeUF6CxNwUAi2O0XWJR6aBSA3sCCBjUnvsO5oG/BVU1hqOMyRrHJEGV5fs6AjkLz8JnuzIbKXJm2amAUb3qVwRJsIjipIW5Hc89wfSq0e8bl3tdNiHQ5UazDL7k47MuvSJGzMS+hBTIlfs3UcuU6bj4V6Z67hQc4LSd6a3C1dnl+rjENw7arikIrTT30Y6RQvhCpzjmH89ArVYPOotNV7/6bzwg4qidBVoR5p6hDx+JUzcjnFLMVotpNOmJp8ARfzCCXhvbYtk3HPjGS7r1AtMGWK6Rb8Nfw9oVRkulcB8Hv9U53z32Qol0hG1w55iNJ2XIDfT5CLsXmLHX04ZTnqv6YF9aG2zrmFJXwoRcpP6545mMlhMc6VTAHk1757FJDLE1LzqRczD7qAj6EHd/jjcO63dp/QCNKGlKpxbjtOjkiShC43ne2ri/E0msIGVHIKQS88d76lxv79OLsC1yz/3V8Ro2rWYXxdkqBOmqxK9KX3LYAQsDyytwphyab3xWxq/mQBDJgSMpO2Aow3TLGXVEM2wkCcZlDB5M2QP7bzGFTv45BDx3Jh2bOEwVwIJSx8y4kJaHTjZ5LVkyZjgo/IvK3I1Ph4dNYSU6xC2ZZHf/9ZNFWPWHJ714XPXZWM33bUB8K7OE= X-Forefront-Antispam-Report: CIP:165.204.84.17;CTRY:US;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:satlexmb08.amd.com;PTR:InfoDomainNonexistent;CAT:NONE;SFS:(13230040)(7416014)(376014)(23010399003)(36860700016)(1800799024)(82310400026)(261022105027099003)(261021121427099003)(261022075727099003)(3023799007)(10067099003)(56012099006)(22082099003)(18002099003)(13003099007)(11063799006)(261026140227099003);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: Xhr+VhoT710W9a6zFAymbjs+ClVI1GC+OPyyhKLjZpx519xJCOaFilZctDk30jH3D1Q5UWzszzQHZFBqg0SMhbtDur5oe8fIcfFsJ8sWEr4Ry++Bg9RRXY/RBtrVjr32HBzs5Mw6ns34hdXSMXxRnBW4xe7dXasH3d9DSzQYZ4/jV27Fp4bFQrBp2UWMW0+Wbp9u9z0gPq4hAj312eWS2lm7pkIHkaVn7Hierz53DAGCoGXqZZYaw2+Z1jlNbDxnWKf76/uFylwVeSjvVDK3keqccHn6FPDtwuxgpAzuYcLSPXZGL26erfNBid9s0hj0Ye2O2K80MZwB+/kGOyKP0gdBLwlv8lE2Li+Ta+90SqUZ/J07hq8vG4iSHeGO5GMCHVXYVK7BpUZLgXj9IbSQKe2MX0LfTfPpQhYluHAcvP+gwFHrDZx1Wg4cUHYgLOqX X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 27 Oct 2026 05:23:29.4783 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 76aad62b-c112-49c4-2fe4-08df33ea6f7c 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=[satlexmb08.amd.com] X-MS-Exchange-CrossTenant-AuthSource: CY7PEPF000000ED.namprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH8PR12MB8605 > I found an issue with ibs_op sampling that I can reproduce on my AMD > Zen3 laptop. Under full CPU load, sampling PMIs stop arriving on each > CPU, one after another. Reading MSR_AMD64_IBSOPCTL (0xc0011033) while > perf is still running shows the hardware has latched a completed sample > (IBS_OP_ENABLE=1, IBS_OP_VAL=1, IBS_OP_CUR_CNT frozen) and is waiting > for an NMI that never arrives. The CPU never recovers on its own. > > I am really not very familiar with CPU, so I would appreciate any > guidance on whether this is known and what to test next. This is a known Zen3 hardware bug. The workaround involves opening a PMC event alongside the IBS event so that the IBS sample is acknowledged during the PMC NMI, thereby resuming the stalled IBS instance. More details in The Revision guide: https://bugzilla.kernel.org/attachment.cgi?id=311307 Erratum 1285 Processor May Fail to Report IBS (Instruction Based Sampling) Performance Sample Thanks, Ravi