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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8A5D7C369AB for ; Mon, 21 Apr 2025 17:29:10 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 7F4C56B000C; Mon, 21 Apr 2025 13:29:09 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 7A4A16B000D; Mon, 21 Apr 2025 13:29:09 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 693586B000E; Mon, 21 Apr 2025 13:29:09 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) by kanga.kvack.org (Postfix) with ESMTP id 4D27E6B000C for ; Mon, 21 Apr 2025 13:29:09 -0400 (EDT) Received: from smtpin26.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay03.hostedemail.com (Postfix) with ESMTP id 80BE0B675C for ; Mon, 21 Apr 2025 17:29:09 +0000 (UTC) X-FDA: 83358736818.26.CC0E9E8 Received: from tor.source.kernel.org (tor.source.kernel.org [172.105.4.254]) by imf20.hostedemail.com (Postfix) with ESMTP id EDD321C0009 for ; Mon, 21 Apr 2025 17:29:07 +0000 (UTC) Authentication-Results: imf20.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=aG30YlAd; dmarc=pass (policy=quarantine) header.from=kernel.org; spf=pass (imf20.hostedemail.com: domain of djwong@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=djwong@kernel.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1745256548; a=rsa-sha256; cv=none; b=GBDMm5dM7s3ZMTIP/8wMrpsoCNTFCjFKCKbZAYNYVwbqwp2wB1mxK4NROYF5mJTotPEufg drj4/Vl9luNiKKnDA95R+OHGWkgP26pP2m6BUj2IUE/qGcqbb8EGJPLf8HHyt/vvvhYNJJ 0qWSyxtHZrWlYf5o5MzgL9fZXeghJzc= ARC-Authentication-Results: i=1; imf20.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=aG30YlAd; dmarc=pass (policy=quarantine) header.from=kernel.org; spf=pass (imf20.hostedemail.com: domain of djwong@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=djwong@kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1745256547; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=WWXfD3ClAOY0LGYmgssyeTDdsj1uKdlTjSb1i7LkfBM=; b=LYZZzd8ElQ7tbeurNg/Gg5dMx9UPaQcy1HaXTHodWhq8XCnrvyDzOdqf0oSu7WKR/JxJ2j kJfYau0/mt6xy76WgwGBr2OmS1LvL4adPwC0WJEc4gAz2DhZhO8CPj3nWJLMed4qzpO3bh UNCz7CHYB5rgsuzas+xUuWqIVtt9YF0= Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by tor.source.kernel.org (Postfix) with ESMTP id 4B49760008; Mon, 21 Apr 2025 17:28:48 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 09709C4CEE4; Mon, 21 Apr 2025 17:29:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1745256547; bh=9w835CH4Lpw1ec8mSrBQiItR8xXYrvySZLtlE31VjzY=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=aG30YlAdE7B2ScDYoxtkBenyZ03iry07qTaX8LuzvGsgNrTT0K316L0/J8jK4hlMq 4o2r4pDC86dq4fVcLT0t5L7U8qrDfHVyE+BGr7U0OVc7n1QY3axuR9ZNzvvLwy7tMk gnD7gk5l1FLsmgIhspo1DKKErZTlc5p/SwQu1Uw7Tzvggi7Yv4OBZRjh4kggvC9xWc c9PT9qXpemgtZ4m6GfCNtcF7Oqf5OF6It4k2AAfRpWgjKbvOd+wqeD8p+LkiH+DuO3 GBPwbgmIRajxtQb0x3lATw+S7xEVAw+UE0aZNKrtpnSrOuG1NTcWhXbsGn+jUrQrb4 ujQNv0dcYyuGg== Date: Mon, 21 Apr 2025 10:29:06 -0700 From: "Darrick J. Wong" To: Qu Wenruo Cc: Linux Memory Management List , linux-btrfs Subject: Re: Sleep inside atomic for aarch64, triggered by generic/482 Message-ID: <20250421172906.GA25651@frogsfrogsfrogs> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: EDD321C0009 X-Stat-Signature: kz9shi14oyj9ze4jaorntyemei4bjwz9 X-Rspam-User: X-HE-Tag: 1745256547-690128 X-HE-Meta: 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 2flLBvQb eRnbaapyE2jNQWosD0kXrxtN4exBjEm/d2Rj0mur3MDzMFHgRM7Kn3iaz4qeWxtYnKitOXlCm0eMrCfDE+A6DofA6pmxG+88uY0FC7nOLBD0at+3qlesjhhGRNWtgrlFtCzd18BeQHEvgqRhthF3rZtKM6zP+9svoAYgKkA3MC26HoCvig2xRnMG/Jya1QDlEG0971rvShr7LVzyM11qLvEEPzyRSXVB8RFhyVMYAmBHcPYJ3wYvFTBNML1S92ZKaUNDE6AbHVMNDTMDQi2sWwfGB1BttPa/n08KzW1kDouqnpRm0khKV+eN7TU3q+8xHVU86C4kpTXmFPQW6cHbAZkI2Osc1OFcFZUCF X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Sun, Apr 20, 2025 at 08:24:12PM +0930, Qu Wenruo wrote: > Hi, > > Recently I hit two dmesg reports from generic/482, on aarch64 64K page size > with 4K fs block size. > > The involved warning looks like this: > > 117645.139610] BTRFS info (device dm-13): using free-space-tree > [117645.146707] BTRFS info (device dm-13): start tree-log replay > [117645.158598] BTRFS info (device dm-13): last unmount of filesystem > 214efad4-5c63-49b6-ad29-f09c4966de33 > [117645.322288] BUG: sleeping function called from invalid context at > mm/util.c:743 > [117645.322312] in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 46, > name: kcompactd0 > [117645.322325] preempt_count: 1, expected: 0 > [117645.322329] RCU nest depth: 0, expected: 0 > [117645.322338] CPU: 3 UID: 0 PID: 46 Comm: kcompactd0 Tainted: G W OE > 6.15.0-rc2-custom+ #116 PREEMPT(voluntary) > [117645.322343] Tainted: [W]=WARN, [O]=OOT_MODULE, [E]=UNSIGNED_MODULE > [117645.322345] Hardware name: QEMU KVM Virtual Machine, BIOS unknown > 2/2/2022 > [117645.322347] Call trace: > [117645.322349] show_stack+0x34/0x98 (C) > [117645.322360] dump_stack_lvl+0x60/0x80 > [117645.322366] dump_stack+0x18/0x24 > [117645.322370] __might_resched+0x130/0x168 > [117645.322375] folio_mc_copy+0x54/0xa8 > [117645.322382] __migrate_folio.isra.0+0x5c/0x1f8 > [117645.322387] __buffer_migrate_folio+0x28c/0x2a0 > [117645.322391] buffer_migrate_folio_norefs+0x1c/0x30 > [117645.322395] move_to_new_folio+0x94/0x2c0 > [117645.322398] migrate_pages_batch+0x7e4/0xd10 > [117645.322402] migrate_pages_sync+0x88/0x240 > [117645.322405] migrate_pages+0x4d0/0x660 > [117645.322409] compact_zone+0x454/0x718 > [117645.322414] compact_node+0xa4/0x1b8 > [117645.322418] kcompactd+0x300/0x458 > [117645.322421] kthread+0x11c/0x140 > [117645.322426] ret_from_fork+0x10/0x20 > [117645.400370] BTRFS: device fsid 214efad4-5c63-49b6-ad29-f09c4966de33 > devid 1 transid 31 /dev/mapper/thin-vol.482 (253:13) scanned by mount > (924470) > [117645.404282] BTRFS info (device dm-13): first mount of filesystem > 214efad4-5c63-49b6-ad29-f09c4966de33 > > Again this has no btrfs involved in the call trace. > > This looks exactly like the report here: > > https://lore.kernel.org/linux-mm/67f6e11f.050a0220.25d1c8.000b.GAE@google.com/ > > However there are something new here: > > - The target fs is btrfs, no large folio support yet > At least the branch I'm testing (based on v6.15-rc2) doesn't support > folio. > > Furthermore since it's btrfs, there is no buffer_head usage involved. > (But the rootfs is indeed ext4) Doesn't matter; the block device can create large folios in its page cache and blkid reading the bdev can create buffer heads. willy's workaround in: https://lore.kernel.org/linux-fsdevel/Z_VwF1MA-R7MgDVG@casper.infradead.org/ works enough to make this go away. --D > > - Arm64 64K page size with 4K block size > It's less common than x86_64. > > Fortunately I can reproduce the bug reliable, it takes around 3~10 runs to > hit it. > > Hope this report would help a little. > Thanks, > Qu >