Hi Matthew, and Andrew, On Sat, Mar 12, 2022 at 7:56 AM Matthew Wilcox <willy@xxxxxxxxxxxxx> wrote: > > On Fri, Mar 11, 2022 at 08:43:57PM +0100, David Hildenbrand wrote: > > Hi, > > > > playing with swapfiles on random file systems, I stumbled over the > > following nilfs issue (and reproduced it on latest greatest > > linux/master -- v5.17-rc7+). I did not try finding out when this > > was introduced and I did not run into this issue on other file > > systems I tried. > > It's a known bug in NILFS, and I think yours is the fifth report > of it dating back eight months. The root cause of this issue is that NILFS uses two page caches per inode, one for data blocks and another for b-tree node blocks. Even though __folio_end_writeback(), __folio_start_writeback(), and __folio_mark_dirty() acquire lock for mapping->i_pages, inode_to_wb(inode) inside them performs lockdep test for the former one (i.e. inode->i_mapping->i_pages.xa_lock). So, mark_buffer_dirty(), end_page_writeback(), and set_page_writeback() for pages in the latter NILFS specific page cache hit the LOCKDEP warning. I tried to find a way to resolve this, but have no good idea so far. Now I'm thinking of deprecating the NILFS driver (and then proposing its removal after a period) rather than making big modifications to NILFS or others. Any opinions or objections for this ? Matthew, sorry for annoying you for those repetitive reports. To David, NILFS does not support swap files. The error of mkswap is it's result. Regards, Ryusuke Konishi > > fourth: > https://lore.kernel.org/all/CAKFNMon7WkjF3wKD640nH1uXX=TWop2UfrS=Y0Mawf6rFYvY7Q@xxxxxxxxxxxxxx/ > third: > https://lore.kernel.org/all/YXrYvIo8YRnAOJCj@xxxxxxxxxxxxxxxxxxxx/ > second: > https://lore.kernel.org/all/0000000000003a5b5905cf6c5ee7@xxxxxxxxxx/ > first: > https://lore.kernel.org/all/000000000000dd0bf405c96878b9@xxxxxxxxxx/ > > So ... I guess just don't use nilfs? > > > [root@vm-0 ~]# mkfs.nilfs2 /dev/vdc > > WARNING: Device /dev/vdc appears to contain an existing xfs superblock. > > WARNING: All data will be lost after format! > > > > DO YOU REALLY WANT TO FORMAT DEVICE /dev/vdc? > > > > Continue? [y/N] y > > mkfs.nilfs2 (nilfs-utils 2.2.8) > > Start writing file system initial data to the device > > Blocksize:4096 Device:/dev/vdc Device Size:32212254720 > > File system initialization succeeded !! > > [root@vm-0 ~]# mount /dev/vdc /mnt/swap > > [ 51.908189] NILFS version 2 loaded > > [root@vm-0 ~]# dd if=/dev/zero of=/mnt/swap/swapfile bs=1024 count=1048576, > > [ 163.245821] ------------[ cut here ]------------ > > [ 163.246577] WARNING: CPU: 7 PID: 4529 at include/linux/backing-dev.h:269 __folio_mark_dirty+0x31d/0x3b0 > > [ 163.247705] Modules linked in: nilfs2 rfkill isofs intel_rapl_msr intel_rapl_common kvm_amd iTCO_wdt ccp intel_pmc_bxt iTCO_vendor_support kvm irqbypass joydev i2c_i801 pcspkr i2c_smbus lpc_ich drm fuse ip_tag > > [ 163.251013] CPU: 7 PID: 4529 Comm: dd Kdump: loaded Tainted: G W 5.17.0-rc7+ #57 > > [ 163.252035] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.15.0-29-g6a62e0cb0dfe-prebuilt.qemu.org 04/01/2014 > > [ 163.253299] RIP: 0010:__folio_mark_dirty+0x31d/0x3b0 > > [ 163.253875] Code: e8 78 e0 ad 00 85 c0 0f 85 33 fe ff ff 48 8b 83 a8 01 00 00 be ff ff ff ff 48 8d 78 70 e8 5b e0 ad 00 85 c0 0f 85 16 fe ff ff <0f> 0b e9 0f fe ff ff e8 87 e1 ad 00 85 c0 74 89 80 3d 8d 2c 921 > > [ 163.256034] RSP: 0018:ffffacba489b38a8 EFLAGS: 00010046 > > [ 163.256646] RAX: 0000000000000000 RBX: ffff973e08ff6370 RCX: 0000000000000001 > > [ 163.257485] RDX: 0000000000000000 RSI: ffffffff8b5d4335 RDI: ffffffff8b668ab6 > > [ 163.258306] RBP: 0000000000000282 R08: 0000000000000000 R09: 0000000000000030 > > [ 163.259127] R10: ffff973e089641a8 R11: 0000000000004000 R12: ffff973e08ff6138 > > [ 163.259945] R13: 0000000000000001 R14: 0000000000000001 R15: fffff3b08452fbc0 > > [ 163.260796] FS: 00007ff23cc945c0(0000) GS:ffff97455fb80000(0000) knlGS:0000000000000000 > > [ 163.261731] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > > [ 163.262432] CR2: 000055d0601de000 CR3: 00000001142a6000 CR4: 0000000000350ee0 > > [ 163.263263] Call Trace: > > [ 163.263568] <TASK> > > [ 163.263845] mark_buffer_dirty+0x10f/0x170 > > [ 163.264366] nilfs_btree_convert_and_insert+0x3f9/0x490 [nilfs2] > > [ 163.265126] nilfs_bmap_insert+0xc6/0x110 [nilfs2] > > [ 163.265740] ? lock_is_held_type+0xe4/0x140 > > [ 163.266260] nilfs_mdt_get_block+0x190/0x3b0 [nilfs2] > > [ 163.266898] ? lock_release+0x139/0x2d0 > > [ 163.267366] nilfs_palloc_get_block+0x5e/0xd0 [nilfs2] > > [ 163.267978] nilfs_palloc_get_entry_block+0x88/0x90 [nilfs2] > > [ 163.268682] nilfs_dat_prepare_alloc+0x30/0x60 [nilfs2] > > [ 163.269314] nilfs_direct_insert+0x111/0x140 [nilfs2] > > [ 163.269915] nilfs_bmap_insert+0xa8/0x110 [nilfs2] > > [ 163.270490] ? rcu_read_lock_sched_held+0x3f/0x60 > > [ 163.271080] ? trace_nilfs2_transaction_transition+0x29/0xd0 [nilfs2] > > [ 163.271836] ? nilfs_transaction_begin+0x150/0x2f0 [nilfs2] > > [ 163.272498] nilfs_get_block+0xcd/0x200 [nilfs2] > > [ 163.273061] __block_write_begin_int+0x11e/0x630 > > [ 163.273664] ? __nilfs_mark_inode_dirty+0xa0/0xa0 [nilfs2] > > [ 163.274335] ? __nilfs_mark_inode_dirty+0xa0/0xa0 [nilfs2] > > [ 163.274980] block_write_begin+0x53/0x110 > > [ 163.275461] nilfs_write_begin+0x52/0xb0 [nilfs2] > > [ 163.276034] generic_perform_write+0xac/0x1d0 > > [ 163.276559] ? file_update_time+0x3e/0x120 > > [ 163.277053] ? lock_acquire+0xd4/0x2d0 > > [ 163.277540] __generic_file_write_iter+0xdb/0x1a0 > > [ 163.278122] generic_file_write_iter+0x5d/0xb0 > > [ 163.278695] new_sync_write+0x10e/0x190 > > [ 163.279197] vfs_write+0x29c/0x3a0 > > [ 163.279632] ksys_write+0x58/0xd0 > > [ 163.280068] do_syscall_64+0x3b/0x90 > > [ 163.280501] entry_SYSCALL_64_after_hwframe+0x44/0xae > > [ 163.281107] RIP: 0033:0x7ff23cbb9e87 > > [ 163.281591] Code: 0d 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 48 89 54 24 18 48 89 744 > > [ 163.283807] RSP: 002b:00007ffff781cf58 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 > > [ 163.284673] RAX: ffffffffffffffda RBX: 0000000000000400 RCX: 00007ff23cbb9e87 > > [ 163.285530] RDX: 0000000000000400 RSI: 000055d0601de000 RDI: 0000000000000001 > > [ 163.286389] RBP: 000055d0601de000 R08: 000055d0601dd5a0 R09: 00007ff23cc8ca60 > > [ 163.287233] R10: 000055d0601de000 R11: 0000000000000246 R12: 0000000000000000 > > [ 163.288097] R13: 0000000000000000 R14: 0000000000000400 R15: 000055d0601de000 > > [ 163.288923] </TASK> > > [ 163.289197] irq event stamp: 4362 > > [ 163.289597] hardirqs last enabled at (4361): [<ffffffff8a3a3f04>] folio_memcg_lock+0x144/0x240 > > [ 163.290667] hardirqs last disabled at (4362): [<ffffffff8add94d0>] _raw_spin_lock_irqsave+0x60/0x70 > > [ 163.291720] softirqs last enabled at (4176): [<ffffffffc0742bc6>] nilfs_palloc_commit_alloc_entry+0x16/0x60 [nilfs2] > > [ 163.292929] softirqs last disabled at (4172): [<ffffffff8a308c6e>] wb_wakeup_delayed+0x2e/0x70 > > [ 163.293952] ---[ end trace 0000000000000000 ]--- > > [ 163.419320] ------------[ cut here ]------------ > > [ 163.420427] WARNING: CPU: 11 PID: 4522 at include/linux/backing-dev.h:269 __folio_start_writeback+0x2cf/0x2e0 > > [ 163.422157] Modules linked in: nilfs2 rfkill isofs intel_rapl_msr intel_rapl_common kvm_amd iTCO_wdt ccp intel_pmc_bxt iTCO_vendor_support kvm irqbypass joydev i2c_i801 pcspkr i2c_smbus lpc_ich drm fuse ip_tag > > [ 163.426893] CPU: 11 PID: 4522 Comm: segctord Kdump: loaded Tainted: G W 5.17.0-rc7+ #57 > > [ 163.428510] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.15.0-29-g6a62e0cb0dfe-prebuilt.qemu.org 04/01/2014 > > [ 163.430462] RIP: 0010:__folio_start_writeback+0x2cf/0x2e0 > > [ 163.431433] Code: 24 10 85 c0 0f 85 6f ff ff ff 48 8b 82 a8 01 00 00 83 ce ff 48 8d 78 70 e8 fe f4 ad 00 48 8b 54 24 10 85 c0 0f 85 4f ff ff ff <0f> 0b e9 48 ff ff ff 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 000 > > [ 163.434154] RSP: 0018:ffffacba489abd10 EFLAGS: 00010046 > > [ 163.434902] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000001 > > [ 163.435902] RDX: ffff973e13023370 RSI: ffffffff8b5d4335 RDI: ffffffff8b668ab6 > > [ 163.436913] RBP: 0000000000000001 R08: 0000000000000002 R09: 0000000000000001 > > [ 163.437912] R10: 0000000000000000 R11: 000000000003b460 R12: ffff974587182000 > > [ 163.438912] R13: 0000000000000001 R14: ffff973e13023130 R15: fffff3b0841ab640 > > [ 163.439913] FS: 0000000000000000(0000) GS:ffff974d5f800000(0000) knlGS:0000000000000000 > > [ 163.441039] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > > [ 163.441858] CR2: 00007f8c9c010cf8 CR3: 0000000883614000 CR4: 0000000000350ee0 > > [ 163.442862] Call Trace: > > [ 163.443243] <TASK> > > [ 163.443585] nilfs_begin_page_io+0x63/0x80 [nilfs2] > > [ 163.444298] nilfs_segctor_do_construct+0xb28/0x1c80 [nilfs2] > > [ 163.445134] nilfs_segctor_construct+0x1f4/0x2f0 [nilfs2] > > [ 163.445915] nilfs_segctor_thread+0x10f/0x400 [nilfs2] > > [ 163.446666] ? nilfs_segctor_construct+0x2f0/0x2f0 [nilfs2] > > [ 163.447441] kthread+0xf2/0x120 > > [ 163.447761] ? kthread_complete_and_exit+0x20/0x20 > > [ 163.448224] ret_from_fork+0x22/0x30 > > [ 163.448588] </TASK> > > [ 163.448820] irq event stamp: 29944 > > [ 163.449158] hardirqs last enabled at (29943): [<ffffffff8a3a3f04>] folio_memcg_lock+0x144/0x240 > > [ 163.449981] hardirqs last disabled at (29944): [<ffffffff8add94d0>] _raw_spin_lock_irqsave+0x60/0x70 > > [ 163.450838] softirqs last enabled at (17046): [<ffffffff8a0f0c2b>] __irq_exit_rcu+0xfb/0x150 > > [ 163.451638] softirqs last disabled at (17041): [<ffffffff8a0f0c2b>] __irq_exit_rcu+0xfb/0x150 > > [ 163.452433] ---[ end trace 0000000000000000 ]--- > > [ 163.460194] ------------[ cut here ]------------ > > [ 163.460654] WARNING: CPU: 11 PID: 4522 at include/linux/backing-dev.h:269 __folio_end_writeback+0x38b/0x420 > > [ 163.461537] Modules linked in: nilfs2 rfkill isofs intel_rapl_msr intel_rapl_common kvm_amd iTCO_wdt ccp intel_pmc_bxt iTCO_vendor_support kvm irqbypass joydev i2c_i801 pcspkr i2c_smbus lpc_ich drm fuse ip_tag > > [ 163.464027] CPU: 11 PID: 4522 Comm: segctord Kdump: loaded Tainted: G W 5.17.0-rc7+ #57 > > [ 163.464876] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.15.0-29-g6a62e0cb0dfe-prebuilt.qemu.org 04/01/2014 > > [ 163.465911] RIP: 0010:__folio_end_writeback+0x38b/0x420 > > [ 163.466410] Code: 0f 85 53 fe ff ff 49 8b 87 a8 01 00 00 83 ce ff 48 8d 78 70 e8 86 db ad 00 4c 8b 0c 24 4c 8b 44 24 08 85 c0 0f 85 2f fe ff ff <0f> 0b e9 28 fe ff ff 48 8b 35 67 1a 52 01 b8 01 00 00 00 48 c77 > > [ 163.468102] RSP: 0018:ffffacba489abd48 EFLAGS: 00010046 > > [ 163.468588] RAX: 0000000000000000 RBX: ffff973e13023130 RCX: 0000000000000001 > > [ 163.469241] RDX: 0000000000000000 RSI: ffffffff8b5d4335 RDI: ffffffff8b668ab6 > > [ 163.469897] RBP: fffff3b0841ab640 R08: 0000000000000206 R09: ffff973e13023138 > > [ 163.470547] R10: 0000000000000000 R11: 000000000003b6e0 R12: fffff3b0848c9e01 > > [ 163.471213] R13: 0000000000000001 R14: 0000000000000001 R15: ffff973e13023370 > > [ 163.471869] FS: 0000000000000000(0000) GS:ffff974d5f800000(0000) knlGS:0000000000000000 > > [ 163.472604] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > > [ 163.473137] CR2: 00007f8c9c010cf8 CR3: 0000000883614000 CR4: 0000000000350ee0 > > [ 163.473790] Call Trace: > > [ 163.474035] <TASK> > > [ 163.474253] folio_end_writeback+0x2a/0xc0 > > [ 163.474647] nilfs_segctor_do_construct+0x181f/0x1c80 [nilfs2] > > [ 163.475200] nilfs_segctor_construct+0x1f4/0x2f0 [nilfs2] > > [ 163.475710] nilfs_segctor_thread+0x10f/0x400 [nilfs2] > > [ 163.476196] ? nilfs_segctor_construct+0x2f0/0x2f0 [nilfs2] > > [ 163.476733] kthread+0xf2/0x120 > > [ 163.477046] ? kthread_complete_and_exit+0x20/0x20 > > [ 163.477507] ret_from_fork+0x22/0x30 > > [ 163.477861] </TASK> > > [ 163.478082] irq event stamp: 51868 > > [ 163.478408] hardirqs last enabled at (51867): [<ffffffff8a3a3f04>] folio_memcg_lock+0x144/0x240 > > [ 163.479233] hardirqs last disabled at (51868): [<ffffffff8add94d0>] _raw_spin_lock_irqsave+0x60/0x70 > > [ 163.480066] softirqs last enabled at (35082): [<ffffffff8a0f0c2b>] __irq_exit_rcu+0xfb/0x150 > > [ 163.480861] softirqs last disabled at (35075): [<ffffffff8a0f0c2b>] __irq_exit_rcu+0xfb/0x150 > > [ 163.481650] ---[ end trace 0000000000000000 ]--- > > 1048576+0 records in > > 1048576+0 records out > > 1073741824 bytes (1.1 GB, 1.0 GiB) copied, 11.4729 s, 93.6 MB/s > > > > > > > > After that, the fs behaves weird: > > > > [root@vm-0 ~]# mkswap /mnt/swap/swapfile > > mkswap: /mnt/swap/swapfile: insecure permissions 0644, 0600 suggested. > > Setting up swapspace version 1, size = 1024 MiB (1073737728 bytes) > > no label, UUID=c0fb0051-c7e4-4235-b4a0-b992a39ba71f > > [root@vm-0 ~]# swapon /mnt/swap/swapfile > > swapon: /mnt/swap/swapfile: insecure permissions 0644, 0600 suggested. > > [ 215.368832] swapon: swapfile has holes > > swapon: /mnt/swap/swapfile: swapon failed: Invalid argument > > > > > > Even another dd run doesn't do the trick and swapon keeps complaining > > about holes. Not sure if the latter is just expected on nifs or a side product > > of the warnings. > > > > -- > > Thanks, > > > > David / dhildenb > >