From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C9FFA1A9F87; Sun, 26 Oct 2025 01:31:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761442284; cv=none; b=fS1yLQmKqdJF3/FeyCvUum0txXdhokOrEZn3b1bNX8aex+w9gcqAaGI3T8AlUGJ9LQJDYZIsK4VZHDlTPPQdv0z52BKh1At8i6TCwvAc1S0J2RiH4VS1EW+rKgse3mH4LAnhzhTatgLCxTzc2j3VzAOw5cgHsDZf4TIiB9EoXoU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761442284; c=relaxed/simple; bh=idYAbqf0v2257DIEdVXDo9dzrQq/Thb+gPb8TBKEY/w=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=EbGUoTgOdYbwylamHMvbjwmm9x/X01Z6ToDD3M7hIKHR/a+eyRhKR84/o22omdJ4xpvUBsdNurZgPWhIGYgCJgq/zRdsHuHeeWQJBsQu2AfnCOEFV+psUMCSOevbAMj1s2IQGbsJ4D0NeaICIF7oOjuxQZ9ZU6FYCNj+KQFYdNw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=cqhu0AF+; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="cqhu0AF+" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 61D0EC4CEF5; Sun, 26 Oct 2025 01:31:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1761442284; bh=idYAbqf0v2257DIEdVXDo9dzrQq/Thb+gPb8TBKEY/w=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=cqhu0AF+RTOrwaRE5jzqOBVM5efOiAY4QXweVgRe371O9PTdeyRnjsa4Dg5OfiROM HLug04f8Ze9T+MWlb/Z0vMkFyQfGjemR5tt6zZZYLoLj9WxmZpN4ynmlcsvQshro7L 07jTS6Di4Nbhy+P1NyEXBQNw/u7oTLYPBvLPCld7lwGRoIJi+qEEwIw1bygq5qvbCa t6SAJlkgSZxM45f16wTXwW+4I2jD6l8lkqpJYFHhC4/wt23qLqHQZP4Bi2RlR6Q7Dy zVF11NAuac9bVzvalTccEzK9dnOUZuOtfpvAvQQ2LbGdXFrY49ZNIavbxQYBdEV9PH FLrpMS7+7zCcw== Message-ID: Date: Sat, 25 Oct 2025 20:31:19 -0500 Precedence: bulk X-Mailing-List: linux-pm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [REGRESSION][BISECTED] Hibernation: WARNING at kernel/power/main.c:48 pm_restrict_gfp_mask (was: "[PATCH v1] PM: hibernate: Restrict GFP mask in hibernation_snapshot()") To: Askar Safin , rafael@kernel.org Cc: gregkh@linuxfoundation.org, guoqing.zhang@amd.com, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, mario.limonciello@amd.com, todd.e.brandt@linux.intel.com, torvalds@linuxfoundation.org, regressions References: <5924662.DvuYhMxLoT@rafael.j.wysocki> <20251025050812.421905-1-safinaskar@gmail.com> Content-Language: en-US From: Mario Limonciello In-Reply-To: <20251025050812.421905-1-safinaskar@gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 10/25/25 12:08 AM, Askar Safin wrote: > "Rafael J. Wysocki" : >> From: Rafael J. Wysocki >> >> Commit 12ffc3b1513e ("PM: Restrict swap use to later in the suspend >> sequence") incorrectly removed a pm_restrict_gfp_mask() call from >> hibernation_snapshot(), so memory allocations involving swap are not >> prevented from being carried out in this code path any more which may >> lead to serious breakage. > > #regzbot introduced: 449c9c02537a146ac97ef962327a221e21c9cab3 > > This commit introduced regression: now I see WARNING every time when > I hibernate. The bug reproduces both on real hardware and in Qemu. > > Here is script I used to reproduce this bug in Qemu: > https://zerobin.net/?aadae7117a208c0a#Xh8aI5+u3pyk+vKwET7j+yXolLeoSLe/AedcvnNeCLs= > > Here is resulting log (dmesg) on current master (43e9ad0c55a3): > https://zerobin.net/?471d17d0632e7f85#uYne0yUu+rP4KnDbOFFqtCrcDIi6UpQz2uIQw85lcdQ= > > Here is the most interesting part: > > [ 1.735001] PM: Image saving progress: 90% > [ 1.746611] PM: Image saving progress: 100% > [ 1.747208] PM: Image saving done > [ 1.747403] PM: hibernation: Wrote 30164 kbytes in 0.13 seconds (232.03 MB/s) > [ 1.747837] PM: Image size after compression: 8908 kbytes > [ 1.748190] PM: S| > [ 1.750351] ------------[ cut here ]------------ > [ 1.750627] WARNING: CPU: 0 PID: 1 at kernel/power/main.c:48 pm_restrict_gfp_mask+0x3b/0x40 > > On real hardware exactly same thing happens (i. e. WARNING at kernel/power/main.c:48 pm_restrict_gfp_mask). > Thanks for the report, and especially for the simple reproducer! This is pretty similar to the problem we had with hybrid sleep. [1] Link: https://git.kernel.org/torvalds/c/469d80a3712c6 [1] I believe this should help: diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index 14e85ff23551..e15907f28c4c 100644 --- a/kernel/power/hibernate.c +++ b/kernel/power/hibernate.c @@ -721,6 +721,7 @@ static void power_down(void) kernel_restart(NULL); break; case HIBERNATION_PLATFORM: + pm_restore_gfp_mask(); error = hibernation_platform_enter(); if (error == -EAGAIN || error == -EBUSY) { events_check_enabled = false;