From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from verein.lst.de (verein.lst.de [213.95.11.211]) (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 DA9EF221FB1 for ; Mon, 6 Apr 2026 06:19:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=213.95.11.211 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775456400; cv=none; b=QfNu14WFQKJR+heLEcTP7dfsjVkQEeD/JmDAYnfAyMgbRkv0ntJE1CtMag9AHeX6XmP7j1W4strO7BJd8b4AMEjdNeG0dAMqwtyO5Ia5OOQRon10rqiJKJXDuWALZ+5cOFkWW3sXSy+FCVOWc4TM5AJGuX2f74rT6I/nHtVjoQY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775456400; c=relaxed/simple; bh=2+trm8Zl+dWtk8aL48cu6TiHlddR4E78eoE+JrXMaDE=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=GbQE4Af5LnwUaBffxLTSwJ+x434SVj0ivEKerprhH9j85wEzC+udfhxTABo0XjJgApJeds10mjU9wBzpeP/VCSbApeRZuMvx6ARWtoFFbljey8tVAoRVrnQKsPnv92kC04PY7MzYXTEet1HFfJf0L/r2cs+Je+vcpqmI5Q2zvl8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=lst.de; spf=pass smtp.mailfrom=lst.de; arc=none smtp.client-ip=213.95.11.211 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=lst.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=lst.de Received: by verein.lst.de (Postfix, from userid 2407) id CF06A68BFE; Mon, 6 Apr 2026 08:19:55 +0200 (CEST) Date: Mon, 6 Apr 2026 08:19:55 +0200 From: Christoph Hellwig To: Matthew Wilcox Cc: fsverity@lists.linux.dev, Eric Biggers , "Theodore Y. Ts'o" , aalbersh@kernel.org Subject: Re: fsverity and large folios Message-ID: <20260406061955.GH16443@lst.de> References: Precedence: bulk X-Mailing-List: fsverity@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) On Mon, Apr 06, 2026 at 05:58:43AM +0100, Matthew Wilcox wrote: > I suspect that fsverity simply doesn't support large folios today. I tried that with btrfs, which (before the xfs patchset currently pending), and it does indeed seem to lead to a quick assert hitting when running the verity group in xfstests. So we should prevent this from mounting before it gets fixed one way or another: generic/572 [ 88.967330] run fstests generic/572 at 2026-04-06 06:16:47 [snip] [ 90.355104] page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x7fe9a1264 pfn:0x113f65 [ 90.355697] memcg:ffff88810081bc80 [ 90.355921] flags: 0x4000000000000001(locked|zone=2) [ 90.356537] raw: 4000000000000001 0000000000000000 dead000000000122 0000000000000000 [ 90.357061] raw: 00000007fe9a1264 0000000000000000 00000001ffffffff ffff88810081bc80 [ 90.357547] page dumped because: VM_BUG_ON_FOLIO(folio_order(folio) < mapping_min_folio_order(mapping)) [ 90.358132] ------------[ cut here ]------------ [ 90.358417] kernel BUG at mm/filemap.c:858! [ 90.358734] Oops: invalid opcode: 0000 [#1] SMP NOPTI [ 90.359046] CPU: 1 UID: 0 PID: 436 Comm: kworker/u8:4 Not tainted 7.0.0-rc5+ #4020 PREEMPT(full) [ 90.359583] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 [ 90.360165] Workqueue: btrfs-endio simple_end_io_work [ 90.360499] RIP: 0010:__filemap_add_folio+0x4e2/0x560 [ 90.360832] Code: 4c 89 ff e8 90 63 04 00 0f 0b 48 c7 c6 88 6f f5 82 4c 89 ff e8 7f 63 04 00 0f 0b 48 c7 c6 b8 6f f5 82 4c 89 ff e8 6e 63 04 00 <0f> 0b 48 c7 c6 78 dd f3 82 4c 89 ff e8 5d 63 04 00 0f 0b 48 c7 c6 [ 90.361981] RSP: 0018:ffffc90001303828 EFLAGS: 00010246 [ 90.362358] RAX: 000000000000005b RBX: 0000000000000c40 RCX: 0000000000000000 [ 90.362861] RDX: 0000000000000000 RSI: 0000000000000001 RDI: 00000000ffffffff [ 90.363313] RBP: 0000000000000000 R08: 00000000fffeffff R09: ffffffff837fa9e8 [ 90.363768] R10: ffffffff8327aa40 R11: 6d75642065676170 R12: 0000000000000000 [ 90.364233] R13: 0000000000000c40 R14: 0000000000000020 R15: ffffea00044fd940 [ 90.364711] FS: 0000000000000000(0000) GS:ffff8885a7678000(0000) knlGS:0000000000000000 [ 90.365234] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 90.365608] CR2: 00007fac03af5030 CR3: 0000000103f54004 CR4: 0000000000770ef0 [ 90.366059] PKRU: 55555554 [ 90.366232] Call Trace: [ 90.366390] [ 90.366528] ? ret_from_fork+0x19e/0x240 [ 90.366801] ? unwind_get_return_address+0x1e/0x40 [ 90.367098] filemap_add_folio+0xe7/0x270 [ 90.367348] btrfs_read_merkle_tree_page+0x1a1/0x3d0 [ 90.367653] verify_data_block+0xf2/0x700 [ 90.367903] ? ret_from_fork_asm+0x1a/0x30 [ 90.368162] ? stack_depot_save_flags+0x29/0x850 [ 90.368464] ? set_track_prepare+0x45/0x70 [ 90.368731] ? kmem_cache_alloc_noprof+0x2fd/0x370 [ 90.369036] ? alloc_pid+0xc1/0x490 [ 90.369242] ? copy_process+0x116f/0x1af0 [ 90.369500] ? kernel_clone+0x93/0x3f0 [ 90.369737] ? read_extent_buffer+0xde/0x150 [ 90.370000] ? check_root_key+0x39/0xd0 [ 90.370240] ? read_extent_buffer+0xde/0x150 [ 90.370612] ? kernel_fpu_begin_mask+0x89/0x140 [ 90.370930] fsverity_verify_pending_blocks+0x68/0xf0 [ 90.371276] fsverity_add_data_blocks+0xd1/0xf0 [ 90.371577] fsverity_verify_blocks+0x4b/0xb0 [ 90.371870] ? check_inode_key+0x39/0xd0 [ 90.372126] ? read_extent_buffer+0xde/0x150 [ 90.372419] end_folio_read+0x148/0x1b0 [ 90.372675] end_bbio_data_read+0xfb/0x4c0 [ 90.372946] ? update_irq_load_avg+0x42/0x4e0 [ 90.373210] btrfs_check_read_bio+0x3f4/0x440 [ 90.373475] ? _raw_spin_unlock+0x13/0x30 [ 90.373720] ? finish_task_switch.isra.0+0x8b/0x240 [ 90.374016] ? __schedule+0x493/0xef0 [ 90.374242] process_one_work+0x177/0x390 [ 90.374479] worker_thread+0x1bc/0x330 [ 90.374717] ? __pfx_worker_thread+0x10/0x10 [ 90.374976] kthread+0xfe/0x140 [ 90.375164] ? __pfx_kthread+0x10/0x10 [ 90.375384] ret_from_fork+0x19e/0x240 [ 90.375604] ? __pfx_kthread+0x10/0x10 [ 90.375823] ret_from_fork_asm+0x1a/0x30 [ 90.376053] [ 90.376194] Modules linked in: [ 90.376402] ---[ end trace 0000000000000000 ]---