From patchwork Fri Feb 25 06:48:15 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Shawn Guo X-Patchwork-Id: 546368 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 A83A3C433EF for ; Fri, 25 Feb 2022 06:48:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237404AbiBYGs5 (ORCPT ); Fri, 25 Feb 2022 01:48:57 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48550 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237027AbiBYGs5 (ORCPT ); Fri, 25 Feb 2022 01:48:57 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2213718C794; Thu, 24 Feb 2022 22:48:26 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id CD646B82B2D; Fri, 25 Feb 2022 06:48:24 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E6ADAC340E7; Fri, 25 Feb 2022 06:48:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1645771703; bh=4K1giYj+12R2Kkj5i0ab94fJZmq/YtPl2GIZQ2+Qasg=; h=From:To:Cc:Subject:Date:From; b=aUK0CzG7NxKCUcI/2x7fYYZvO53D/IAyGrnExUV/vj9O1nVxs04eGkTlmANqnTENI I5FQgVCJn0yUENmgtdAqRKKudHSx2LCXtLyFzpVrFN3lzUpEza5oP372D8ZjUoHaLf yuJ5oraug0bm8f4Fz8xHNSQNOAILKECLQLUouYgf/i6VaZcxkKOwA2AZtVpMFvCsen LEB1Vz9uO5eIZNmmeNXxrbKLJU2DicwbmiBczjHmq+qGmJ/+VZNg964szy3qZM/AQf y80v3+mD0WIuW4e8/GmDcptAcbmx+ctknTHUHCNXKhCofq2pKQhdU5ui04OfG7km/p mHOl1FtcbHhwQ== From: Shawn Guo To: "Rafael J . Wysocki" Cc: Kevin Hilman , Ulf Hansson , Thierry Strudel , linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, Shawn Guo Subject: [PATCH] PM: domains: Fix sleep-in-atomic bug caused by genpd_debug_remove() Date: Fri, 25 Feb 2022 14:48:15 +0800 Message-Id: <20220225064815.444571-1-shawnguo@kernel.org> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org From: Shawn Guo When a genpd with GENPD_FLAG_IRQ_SAFE gets removed, the following sleep-in-atomic bug will be seen, as genpd_debug_remove() will be called with a spinlock being held. [ 0.029183] BUG: sleeping function called from invalid context at kernel/locking/rwsem.c:1460 [ 0.029204] in_atomic(): 1, irqs_disabled(): 128, non_block: 0, pid: 1, name: swapper/0 [ 0.029219] preempt_count: 1, expected: 0 [ 0.029230] CPU: 1 PID: 1 Comm: swapper/0 Not tainted 5.17.0-rc4+ #489 [ 0.029245] Hardware name: Thundercomm TurboX CM2290 (DT) [ 0.029256] Call trace: [ 0.029265] dump_backtrace.part.0+0xbc/0xd0 [ 0.029285] show_stack+0x3c/0xa0 [ 0.029298] dump_stack_lvl+0x7c/0xa0 [ 0.029311] dump_stack+0x18/0x34 [ 0.029323] __might_resched+0x10c/0x13c [ 0.029338] __might_sleep+0x4c/0x80 [ 0.029351] down_read+0x24/0xd0 [ 0.029363] lookup_one_len_unlocked+0x9c/0xcc [ 0.029379] lookup_positive_unlocked+0x10/0x50 [ 0.029392] debugfs_lookup+0x68/0xac [ 0.029406] genpd_remove.part.0+0x12c/0x1b4 [ 0.029419] of_genpd_remove_last+0xa8/0xd4 [ 0.029434] psci_cpuidle_domain_probe+0x174/0x53c [ 0.029449] platform_probe+0x68/0xe0 [ 0.029462] really_probe+0x190/0x430 [ 0.029473] __driver_probe_device+0x90/0x18c [ 0.029485] driver_probe_device+0x40/0xe0 [ 0.029497] __driver_attach+0xf4/0x1d0 [ 0.029508] bus_for_each_dev+0x70/0xd0 [ 0.029523] driver_attach+0x24/0x30 [ 0.029534] bus_add_driver+0x164/0x22c [ 0.029545] driver_register+0x78/0x130 [ 0.029556] __platform_driver_register+0x28/0x34 [ 0.029569] psci_idle_init_domains+0x1c/0x28 [ 0.029583] do_one_initcall+0x50/0x1b0 [ 0.029595] kernel_init_freeable+0x214/0x280 [ 0.029609] kernel_init+0x2c/0x13c [ 0.029622] ret_from_fork+0x10/0x20 It doesn't seem necessary to call genpd_debug_remove() with the lock, so move it out from locking to fix the problem. Fixes: 718072ceb211 ("PM: domains: create debugfs nodes when adding power domains") Signed-off-by: Shawn Guo Reviewed-by: Ulf Hansson --- drivers/base/power/domain.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c index 5db704f02e71..7e8039d1884c 100644 --- a/drivers/base/power/domain.c +++ b/drivers/base/power/domain.c @@ -2058,9 +2058,9 @@ static int genpd_remove(struct generic_pm_domain *genpd) kfree(link); } - genpd_debug_remove(genpd); list_del(&genpd->gpd_list_node); genpd_unlock(genpd); + genpd_debug_remove(genpd); cancel_work_sync(&genpd->power_off_work); if (genpd_is_cpu_domain(genpd)) free_cpumask_var(genpd->cpus);