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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5A919C25B47 for ; Tue, 24 Oct 2023 16:31:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1343882AbjJXQbH (ORCPT ); Tue, 24 Oct 2023 12:31:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56502 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234798AbjJXQbF (ORCPT ); Tue, 24 Oct 2023 12:31:05 -0400 Received: from desiato.infradead.org (desiato.infradead.org [IPv6:2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6123112B; Tue, 24 Oct 2023 09:31:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=yw1JizmzQa21OHIpxEbqWsvPR+Hf7j2CXdWs4xmNF0k=; b=jyw7JHuwxzc7X7X8xzfcxQNQ1b UjBFZlqt75ASSvoLbUxiITUd7kclX9FIdvcnTPmW7R34OmJNJaey6q//Ob1gJe2KDSsYBG6S1ld+D 0LFxu9pr0ctPh0ET/BczCKmpYg0PZgX9Ct5SgB9pi2RvbgB5F3hb66yBj0ILSJIUXeaR2Krsbn6L6 Fj5eJHWRLKGk1xqoMt0XqlwMdqDuz5M2G3N85hYwoRhAfdfAJYE2ekPn6bmWnilWiErAqNVPMu3YG i0AR6202kThNeaa5o9Hiauquerm5AGL2qqHa96gTJHR+rlfOrK35qlGYv/BKBNxTTYairTWpK68Hc lodsjShg==; Received: from j130084.upc-j.chello.nl ([24.132.130.84] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.96 #2 (Red Hat Linux)) id 1qvKIg-00Fdqo-3A; Tue, 24 Oct 2023 16:30:39 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id A4998300451; Tue, 24 Oct 2023 18:30:38 +0200 (CEST) Date: Tue, 24 Oct 2023 18:30:38 +0200 From: Peter Zijlstra To: Mario Limonciello Cc: Ingo Molnar , Borislav Petkov , Thomas Gleixner , Dave Hansen , Sandipan Das , "H . Peter Anvin" , linux-kernel@vger.kernel.org, x86@kernel.org, linux-pm@vger.kernel.org, rafael@kernel.org, pavel@ucw.cz, linux-perf-users@vger.kernel.org, Ingo Molnar , Arnaldo Carvalho de Melo , Mark Rutland , Alexander Shishkin , Jiri Olsa , Namhyung Kim , Ian Rogers , Adrian Hunter Subject: Re: [PATCH 2/2] perf/x86/amd: Don't allow pre-emption in amd_pmu_lbr_reset() Message-ID: <20231024163038.GC40044@noisy.programming.kicks-ass.net> References: <20231023160018.164054-1-mario.limonciello@amd.com> <20231023160018.164054-3-mario.limonciello@amd.com> <38ea48b4-aaba-4ba4-84a1-e88d6cb9df94@amd.com> <20231024155939.GF33965@noisy.programming.kicks-ass.net> <47518940-2803-4a6b-88fd-8cfc872b4219@amd.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <47518940-2803-4a6b-88fd-8cfc872b4219@amd.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Oct 24, 2023 at 11:04:06AM -0500, Mario Limonciello wrote: > > IIRC this is the hotplug thread running a teardown function on that CPU > > itself. It being a strict per-cpu thread should not trip > > smp_processor_id() wanrs. > > > > BUG: using smp_processor_id() in preemptible [00000000] code: rtcwake/2960 > caller is amd_pmu_lbr_reset+0x19/0xc0 > CPU: 104 PID: 2960 Comm: rtcwake Not tainted 6.6.0-rc6-00002-g3e2c7f3ac51f Very much not the cpuhp/%u thread :/, let me try and figure out how that happens. > #1025 > Call Trace: > > dump_stack_lvl+0x44/0x60 > check_preemption_disabled+0xce/0xf0 > ? __pfx_x86_pmu_dead_cpu+0x10/0x10 > amd_pmu_lbr_reset+0x19/0xc0 > ? __pfx_x86_pmu_dead_cpu+0x10/0x10 > amd_pmu_cpu_reset.constprop.0+0x51/0x60 > amd_pmu_cpu_dead+0x3e/0x90 > x86_pmu_dead_cpu+0x13/0x20 > cpuhp_invoke_callback+0x169/0x4b0 > ? __pfx_virtnet_cpu_dead+0x10/0x10 > __cpuhp_invoke_callback_range+0x76/0xe0 > _cpu_down+0x112/0x270 > freeze_secondary_cpus+0x8e/0x280 > suspend_devices_and_enter+0x342/0x900 > pm_suspend+0x2fd/0x690 > state_store+0x71/0xd0 > kernfs_fop_write_iter+0x128/0x1c0 > vfs_write+0x2db/0x400 > ksys_write+0x5f/0xe0 > do_syscall_64+0x59/0x90 > ? srso_alias_return_thunk+0x5/0x7f > ? count_memcg_events.constprop.0+0x1a/0x30 > ? srso_alias_return_thunk+0x5/0x7f > ? handle_mm_fault+0x1e9/0x340 > ? srso_alias_return_thunk+0x5/0x7f > ? preempt_count_add+0x4d/0xa0 > ? srso_alias_return_thunk+0x5/0x7f > ? up_read+0x38/0x70 > ? srso_alias_return_thunk+0x5/0x7f > ? do_user_addr_fault+0x343/0x6b0 > ? srso_alias_return_thunk+0x5/0x7f > ? exc_page_fault+0x74/0x170 > entry_SYSCALL_64_after_hwframe+0x6e/0xd8 > RIP: 0033:0x7f32f8d14a77 > Code: 10 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 f3 0f 1e fa > 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff > 77 51 c3 48 83 ec 28 48 89 54 24 18 48 89 74 24 > RSP: 002b:00007ffdc648de18 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 > RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007f32f8d14a77 > RDX: 0000000000000004 RSI: 000055b2fc2a5670 RDI: 0000000000000004 > RBP: 000055b2fc2a5670 R08: 0000000000000000 R09: 000055b2fc2a5670 > R10: 00007f32f8e1a2f0 R11: 0000000000000246 R12: 0000000000000004 > R13: 000055b2fc2a2480 R14: 00007f32f8e16600 R15: 00007f32f8e15a00 >