From patchwork Wed Sep 6 04:18:52 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chen Yu X-Patchwork-Id: 720757 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 CB119EB8FAF for ; Wed, 6 Sep 2023 04:19:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229554AbjIFETW (ORCPT ); Wed, 6 Sep 2023 00:19:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55466 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237582AbjIFETW (ORCPT ); Wed, 6 Sep 2023 00:19:22 -0400 Received: from mgamail.intel.com (mgamail.intel.com [192.55.52.88]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4A0C3E76; Tue, 5 Sep 2023 21:19:08 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1693973948; x=1725509948; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=Pc90S/c8932uAvyiduvyGa0QXXHWXOrYk20HoKH2IDo=; b=feETVDyHD1D2CnQumpm0VqR/3oqAKPZPnYHOSkfggD0bp7zbkPygqh1E +QZdr8y1yJuGSjowjFsWLHA1REnPRKyoI8yihFo6gsgSCnd0VUbx7gJkv Oc205fpKyDryCjOrARja65o4xV8lXDYmA0q48V1QmmVshaUoW49timV9T HPa06IKu4paIZ3X1sDLq6SSivf+aOFk4+Flzr+4S9EXO5rTRs9gGLEkl5 BMfa1WRe43RycXVbqxsVevobhCj1q1zNlrfOWjUSwW5cP8dA1m3sphfSq GwjDgeLips6xKsBE6UKT9jz4HChQWh1wDpRtPe8o7LCz1glvNSdY5X8bW g==; X-IronPort-AV: E=McAfee;i="6600,9927,10824"; a="407967868" X-IronPort-AV: E=Sophos;i="6.02,231,1688454000"; d="scan'208";a="407967868" Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Sep 2023 21:19:07 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10824"; a="831483471" X-IronPort-AV: E=Sophos;i="6.02,231,1688454000"; d="scan'208";a="831483471" Received: from chenyu-dev.sh.intel.com ([10.239.62.164]) by FMSMGA003.fm.intel.com with ESMTP; 05 Sep 2023 21:19:05 -0700 From: Chen Yu To: "Rafael J. Wysocki" , Len Brown , Pavel Machek Cc: linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, Chenzhou Feng , Pengfei Xu , Chen Yu , syzbot+38d04642cea49f3a3d2e@syzkaller.appspotmail.com Subject: [PATCH v2 2/2] PM: hibernate: Fix the exclusive get block device in test_resume mode Date: Wed, 6 Sep 2023 12:18:52 +0800 Message-Id: X-Mailer: git-send-email 2.25.1 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org commit 5904de0d735b ("PM: hibernate: Do not get block device exclusively in test_resume mode") fixes a hibernation issue under test_resume mode. That commit is supposed to open the block device in non-exclusive mode when in test_resume. However the code did the opposite, which is against its description. In summary, the swap device is only opened exclusively by swsusp_check() with its corresponding *close(), and must be in non test_resume mode. This is to avoid the race condition that different processes scribble the device at the same time. All the other cases should use non-exclusive mode. Fix it by really disabling exclusive mode under test_resume. Fixes: 5904de0d735b ("PM: hibernate: Do not get block device exclusively in test_resume mode") Reported-by: syzbot+38d04642cea49f3a3d2e@syzkaller.appspotmail.com Closes: https://lore.kernel.org/lkml/000000000000761f5f0603324129@google.com/ Reported-by: Pengfei Xu Signed-off-by: Chen Yu --- kernel/power/hibernate.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index 2b4a946a6ff5..8d35b9f9aaa3 100644 --- a/kernel/power/hibernate.c +++ b/kernel/power/hibernate.c @@ -786,9 +786,9 @@ int hibernate(void) unlock_device_hotplug(); if (snapshot_test) { pm_pr_dbg("Checking hibernation image\n"); - error = swsusp_check(snapshot_test); + error = swsusp_check(false); if (!error) - error = load_image_and_restore(snapshot_test); + error = load_image_and_restore(false); } thaw_processes(); @@ -945,14 +945,14 @@ static int software_resume(void) pm_pr_dbg("Looking for hibernation image.\n"); mutex_lock(&system_transition_mutex); - error = swsusp_check(false); + error = swsusp_check(true); if (error) goto Unlock; /* The snapshot device should not be opened while we're running */ if (!hibernate_acquire()) { error = -EBUSY; - swsusp_close(false); + swsusp_close(true); goto Unlock; } @@ -973,7 +973,7 @@ static int software_resume(void) goto Close_Finish; } - error = load_image_and_restore(false); + error = load_image_and_restore(true); thaw_processes(); Finish: pm_notifier_call_chain(PM_POST_RESTORE); @@ -987,7 +987,7 @@ static int software_resume(void) pm_pr_dbg("Hibernation image not present or could not be loaded.\n"); return error; Close_Finish: - swsusp_close(false); + swsusp_close(true); goto Finish; }