From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932709AbdJ3UOZ (ORCPT ); Mon, 30 Oct 2017 16:14:25 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:53954 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751378AbdJ3UOT (ORCPT ); Mon, 30 Oct 2017 16:14:19 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 45FC760584 Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=tbaicar@codeaurora.org Subject: Re: [ghes_copy_tofrom_phys] BUG: sleeping function called from invalid context at mm/page_alloc.c:4150 To: Linus Torvalds , Borislav Petkov , Len Brown , Tony Luck Cc: Fengguang Wu , Huang Ying , Chen Gong , Linux Kernel Mailing List , Will Deacon , "Rafael J. Wysocki" , Linux ACPI , Timur Tabi References: <20171029225155.qcum5i75awrt5tzm@wfg-t540p.sh.intel.com> <20171029231835.3725fnd5yehlmqob@wfg-t540p.sh.intel.com> <20171030110511.scfrdtlnf5lbdhu5@pd.tnic> From: Tyler Baicar Message-ID: <526e7cf2-0672-e44b-c32f-26128a2dfd37@codeaurora.org> Date: Mon, 30 Oct 2017 16:14:15 -0400 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.4.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/30/2017 1:46 PM, Linus Torvalds wrote: > On Mon, Oct 30, 2017 at 10:20 AM, Linus Torvalds > wrote: >> I will add a "might_sleep()" to ioremap_page_range() itself, so that >> we get this warning more reliably and much eailer. Right now it has >> been hidden by the fact that most of the time the time the page tables >> may be already allocated, but even then it's broken. > Done. It doesn't report anything for me, so _hopefully_ the GHES > driver is the only one that does games like this. See commit > b39ab98e2f47 ("Mark 'ioremap_page_range()' as possibly sleeping"). > > So now it should hopefully warn about this bad usage of page remapping > reliably, at least if you have CONFIG_DEBUG_ATOMIC_SLEEP enabled. > > Can somebody who has a working GHES setup (although Borislav seems to > think no such thing exists) verify? Hello Linus, I have verified that this flags the error for me every time ghes_proc() is used. But I also see it flagged in ARM PMU code: [ 7.381153] BUG: sleeping function called from invalid context at mm/slab.h:420 [ 7.387625] in_atomic(): 0, irqs_disabled(): 128, pid: 11, name: cpuhp/0 [ 7.394310] CPU: 0 PID: 11 Comm: cpuhp/0 Not tainted 4.14.0-rc7 #46 [ 7.400559] Hardware name: Qualcomm Qualcomm Centriq(TM) 2400 Development Platform [ 7.414361] Call trace: [ 7.416797] [] dump_backtrace+0x0/0x270 [ 7.422175] [] show_stack+0x24/0x30 [ 7.427211] [] dump_stack+0x98/0xb8 [ 7.432246] [] ___might_sleep+0x104/0x128 [ 7.437799] [] __might_sleep+0x58/0x90 [ 7.443097] [] kmem_cache_alloc_trace+0x224/0x280 [ 7.449347] [] armpmu_alloc+0x30/0x168 [ 7.454639] [] arm_pmu_acpi_cpu_starting+0x114/0x148 [ 7.461151] [] cpuhp_invoke_callback+0xb8/0x760 [ 7.467226] [] cpuhp_thread_fun+0xa4/0x1b8 [ 7.472872] [] smpboot_thread_fn+0x174/0x250 [ 7.478684] [] kthread+0x114/0x140 [ 7.483632] [] ret_from_fork+0x10/0x1c For a GHES polling source: [ 47.944596] BUG: sleeping function called from invalid context at lib/ioremap.c:164 [ 47.951290] in_atomic(): 1, irqs_disabled(): 128, pid: 0, name: swapper/19 [ 47.958150] CPU: 19 PID: 0 Comm: swapper/19 Tainted: G W 4.14.0-rc7 #46 [ 47.958152] Hardware name: Qualcomm Qualcomm Centriq(TM) 2400 Development Platform [ 47.958154] Call trace: [ 47.958161] [] dump_backtrace+0x0/0x270 [ 47.958165] [] show_stack+0x24/0x30 [ 47.958169] [] dump_stack+0x98/0xb8 [ 47.958174] [] ___might_sleep+0x104/0x128 [ 47.958177] [] __might_sleep+0x58/0x90 [ 47.958180] [] ioremap_page_range+0x40/0x310 [ 47.958185] [] ghes_copy_tofrom_phys+0x1f8/0x240 [ 47.958188] [] ghes_proc+0xb0/0x8f0 [ 47.958190] [] ghes_poll_func+0x20/0x40 [ 47.958196] [] call_timer_fn+0x3c/0x1b0 [ 47.958198] [] expire_timers+0xe8/0x170 [ 47.958201] [] run_timer_softirq+0x13c/0x188 [ 47.958203] [] __do_softirq+0x144/0x33c [ 47.958206] [] irq_exit+0xd0/0x108 [ 47.958210] [] __handle_domain_irq+0x6c/0xc0 [ 47.958212] [] gic_handle_irq+0xcc/0x188 For a GHES interrupt source: [ 265.502603] BUG: sleeping function called from invalid context at lib/ioremap.c:164 [ 265.509296] in_atomic(): 1, irqs_disabled(): 128, pid: 3, name: kworker/0:0 [ 265.516242] CPU: 0 PID: 3 Comm: kworker/0:0 Tainted: G W 4.14.0-rc7 #46 [ 265.516244] Hardware name: Qualcomm Qualcomm Centriq(TM) 2400 Development Platform [ 265.516251] Workqueue: kacpi_notify acpi_os_execute_deferred [ 265.516254] Call trace: [ 265.516258] [] dump_backtrace+0x0/0x270 [ 265.516261] [] show_stack+0x24/0x30 [ 265.516264] [] dump_stack+0x98/0xb8 [ 265.516268] [] ___might_sleep+0x104/0x128 [ 265.516270] [] __might_sleep+0x58/0x90 [ 265.516273] [] ioremap_page_range+0x40/0x310 [ 265.516277] [] ghes_copy_tofrom_phys+0x1f8/0x240 [ 265.516279] [] ghes_proc+0xb0/0x8f0 [ 265.516282] [] ghes_notify_hed+0x50/0x90 [ 265.516286] [] notifier_call_chain+0x5c/0xa0 [ 265.516289] [] __blocking_notifier_call_chain+0x58/0xa0 [ 265.516291] [] blocking_notifier_call_chain+0x3c/0x50 [ 265.516293] [] acpi_hed_notify+0x28/0x30 [ 265.516296] [] acpi_device_notify+0x30/0x40 [ 265.516301] [] acpi_ev_notify_dispatch+0x64/0x74 [ 265.516304] [] acpi_os_execute_deferred+0x24/0x38 [ 265.516308] [] process_one_work+0x1f8/0x488 [ 265.516310] [] worker_thread+0x58/0x4a0 [ 265.516312] [] kthread+0x114/0x140 [ 265.516315] [] ret_from_fork+0x10/0x1c Thanks, Tyler -- Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc. Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.