Buffer I/O error on dev nbd2, logical block 0, async page read Dev nbd2: unable to read RDB block 0 nbd2: unable to read partition table ldm_validate_partition_table(): Disk read failed. Dev nbd2: unable to read RDB block 0 nbd2: unable to read partition table ====================================================== WARNING: possible circular locking dependency detected 6.14.0-rc2-syzkaller-00039-g09fbf3d50205 #0 Tainted: G U ------------------------------------------------------ udevd/28721 is trying to acquire lock: ffff888025ad5358 (&q->q_usage_counter(io)#51){++++}-{0:0}, at: __submit_bio+0x3d1/0x690 block/blk-core.c:628 but task is already holding lock: ffff8880238dabc0 (mapping.invalidate_lock#2){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:932 [inline] ffff8880238dabc0 (mapping.invalidate_lock#2){++++}-{4:4}, at: page_cache_ra_unbounded+0x173/0x7d0 mm/readahead.c:229 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #6 (mapping.invalidate_lock#2){++++}-{4:4}: down_read+0x9a/0x330 kernel/locking/rwsem.c:1524 filemap_invalidate_lock_shared include/linux/fs.h:932 [inline] filemap_fault+0x1845/0x2ca0 mm/filemap.c:3454 __do_fault+0x10a/0x490 mm/memory.c:4977 do_read_fault mm/memory.c:5392 [inline] do_fault mm/memory.c:5526 [inline] do_pte_missing+0xecf/0x3e10 mm/memory.c:4047 handle_pte_fault mm/memory.c:5889 [inline] __handle_mm_fault+0x1166/0x2c60 mm/memory.c:6032 handle_mm_fault+0x3fa/0xaa0 mm/memory.c:6201 faultin_page mm/gup.c:1196 [inline] __get_user_pages+0x773/0x36f0 mm/gup.c:1491 __get_user_pages_locked mm/gup.c:1757 [inline] __gup_longterm_locked+0x212/0x1870 mm/gup.c:2523 gup_fast_fallback+0x1802/0x2690 mm/gup.c:3424 pin_user_pages_fast+0xa8/0x100 mm/gup.c:3530 iov_iter_extract_user_pages lib/iov_iter.c:1844 [inline] iov_iter_extract_pages+0x3a5/0x2010 lib/iov_iter.c:1907 __bio_iov_iter_get_pages block/bio.c:1181 [inline] bio_iov_iter_get_pages+0x37c/0x1100 block/bio.c:1263 __blkdev_direct_IO_simple+0x361/0x820 block/fops.c:80 blkdev_direct_IO+0xabb/0x1c50 block/fops.c:404 blkdev_direct_write block/fops.c:677 [inline] blkdev_write_iter+0x6f9/0xdd0 block/fops.c:744 new_sync_write fs/read_write.c:586 [inline] vfs_write+0x5ae/0x1150 fs/read_write.c:679 ksys_write+0x12b/0x250 fs/read_write.c:731 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #5 (&mm->mmap_lock){++++}-{4:4}: __might_fault mm/memory.c:6840 [inline] __might_fault+0x11b/0x190 mm/memory.c:6833 _inline_copy_from_user include/linux/uaccess.h:162 [inline] _copy_from_user+0x29/0xd0 lib/usercopy.c:18 copy_from_user include/linux/uaccess.h:212 [inline] csum_and_copy_from_user include/net/checksum.h:31 [inline] copy_from_user_iter_csum net/core/skbuff.c:7272 [inline] iterate_ubuf include/linux/iov_iter.h:30 [inline] iterate_and_advance2 include/linux/iov_iter.h:300 [inline] csum_and_copy_from_iter_full+0x218/0x1eb0 net/core/skbuff.c:7284 ip_generic_getfrag+0x175/0x260 net/ipv4/ip_output.c:936 raw6_getfrag+0x1ed/0x270 net/ipv6/raw.c:737 __ip6_append_data.isra.0+0x3dca/0x4650 net/ipv6/ip6_output.c:1701 ip6_append_data+0x1e6/0x500 net/ipv6/ip6_output.c:1856 rawv6_sendmsg+0x15ce/0x4460 net/ipv6/raw.c:920 inet_sendmsg+0x119/0x140 net/ipv4/af_inet.c:851 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg net/socket.c:733 [inline] ____sys_sendmsg+0x907/0xb40 net/socket.c:2573 ___sys_sendmsg+0x135/0x1e0 net/socket.c:2627 __sys_sendmsg+0x16e/0x220 net/socket.c:2659 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #4 (sk_lock-AF_INET6){+.+.}-{0:0}: lock_sock_nested+0x3a/0xf0 net/core/sock.c:3645 lock_sock include/net/sock.h:1624 [inline] inet_autobind+0x1a/0x1a0 net/ipv4/af_inet.c:178 inet_send_prepare+0x317/0x530 net/ipv4/af_inet.c:837 inet_sendmsg+0x43/0x140 net/ipv4/af_inet.c:848 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg net/socket.c:733 [inline] sock_sendmsg+0x324/0x410 net/socket.c:756 __sock_xmit+0x1e8/0x4f0 drivers/block/nbd.c:574 sock_xmit drivers/block/nbd.c:602 [inline] nbd_send_cmd+0x8ec/0x1c90 drivers/block/nbd.c:712 nbd_handle_cmd drivers/block/nbd.c:1174 [inline] nbd_queue_rq+0x941/0x1220 drivers/block/nbd.c:1204 blk_mq_dispatch_rq_list+0x443/0x1dc0 block/blk-mq.c:2120 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:170 [inline] blk_mq_do_dispatch_sched block/blk-mq-sched.c:184 [inline] __blk_mq_sched_dispatch_requests+0xcdf/0x1620 block/blk-mq-sched.c:309 blk_mq_sched_dispatch_requests+0xd8/0x1b0 block/blk-mq-sched.c:331 blk_mq_run_hw_queue+0x239/0x670 block/blk-mq.c:2354 blk_mq_dispatch_plug_list block/blk-mq.c:2866 [inline] blk_mq_flush_plug_list+0x673/0x1c60 block/blk-mq.c:2917 __blk_flush_plug+0x2c5/0x4b0 block/blk-core.c:1213 blk_finish_plug block/blk-core.c:1240 [inline] blk_finish_plug block/blk-core.c:1237 [inline] __submit_bio+0x547/0x690 block/blk-core.c:642 __submit_bio_noacct_mq block/blk-core.c:715 [inline] submit_bio_noacct_nocheck+0x698/0xd70 block/blk-core.c:744 submit_bio_noacct+0x50d/0x1ec0 block/blk-core.c:867 submit_bh fs/buffer.c:2819 [inline] block_read_full_folio+0x812/0xa50 fs/buffer.c:2446 filemap_read_folio+0xc6/0x2a0 mm/filemap.c:2390 do_read_cache_folio+0x263/0x5c0 mm/filemap.c:3960 read_mapping_folio include/linux/pagemap.h:1023 [inline] read_part_sector+0xd4/0x310 block/partitions/core.c:722 adfspart_check_ICS+0xa7/0x8c0 block/partitions/acorn.c:360 check_partition block/partitions/core.c:141 [inline] blk_add_partitions block/partitions/core.c:589 [inline] bdev_disk_changed+0x6c6/0x14e0 block/partitions/core.c:693 blkdev_get_whole+0x187/0x290 block/bdev.c:706 bdev_open+0x2c7/0xe20 block/bdev.c:915 blkdev_open+0x272/0x3f0 block/fops.c:652 do_dentry_open+0x735/0x1c40 fs/open.c:956 vfs_open+0x82/0x3f0 fs/open.c:1086 do_open fs/namei.c:3830 [inline] path_openat+0x1e88/0x2d80 fs/namei.c:3989 do_filp_open+0x20c/0x470 fs/namei.c:4016 do_sys_openat2+0x17a/0x1e0 fs/open.c:1428 do_sys_open fs/open.c:1443 [inline] __do_sys_openat fs/open.c:1459 [inline] __se_sys_openat fs/open.c:1454 [inline] __x64_sys_openat+0x175/0x210 fs/open.c:1454 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #3 (&nsock->tx_lock){+.+.}-{4:4}: __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x19b/0xb10 kernel/locking/mutex.c:730 nbd_handle_cmd drivers/block/nbd.c:1140 [inline] nbd_queue_rq+0x424/0x1220 drivers/block/nbd.c:1204 blk_mq_dispatch_rq_list+0x443/0x1dc0 block/blk-mq.c:2120 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:170 [inline] blk_mq_do_dispatch_sched block/blk-mq-sched.c:184 [inline] __blk_mq_sched_dispatch_requests+0xcdf/0x1620 block/blk-mq-sched.c:309 blk_mq_sched_dispatch_requests+0xd8/0x1b0 block/blk-mq-sched.c:331 blk_mq_run_hw_queue+0x239/0x670 block/blk-mq.c:2354 blk_mq_dispatch_plug_list block/blk-mq.c:2866 [inline] blk_mq_flush_plug_list+0x673/0x1c60 block/blk-mq.c:2917 __blk_flush_plug+0x2c5/0x4b0 block/blk-core.c:1213 blk_finish_plug block/blk-core.c:1240 [inline] blk_finish_plug block/blk-core.c:1237 [inline] __submit_bio+0x547/0x690 block/blk-core.c:642 __submit_bio_noacct_mq block/blk-core.c:715 [inline] submit_bio_noacct_nocheck+0x698/0xd70 block/blk-core.c:744 submit_bio_noacct+0x50d/0x1ec0 block/blk-core.c:867 submit_bh fs/buffer.c:2819 [inline] block_read_full_folio+0x812/0xa50 fs/buffer.c:2446 filemap_read_folio+0xc6/0x2a0 mm/filemap.c:2390 do_read_cache_folio+0x263/0x5c0 mm/filemap.c:3960 read_mapping_folio include/linux/pagemap.h:1023 [inline] read_part_sector+0xd4/0x310 block/partitions/core.c:722 adfspart_check_ICS+0xa7/0x8c0 block/partitions/acorn.c:360 check_partition block/partitions/core.c:141 [inline] blk_add_partitions block/partitions/core.c:589 [inline] bdev_disk_changed+0x6c6/0x14e0 block/partitions/core.c:693 blkdev_get_whole+0x187/0x290 block/bdev.c:706 bdev_open+0x2c7/0xe20 block/bdev.c:915 blkdev_open+0x272/0x3f0 block/fops.c:652 do_dentry_open+0x735/0x1c40 fs/open.c:956 vfs_open+0x82/0x3f0 fs/open.c:1086 do_open fs/namei.c:3830 [inline] path_openat+0x1e88/0x2d80 fs/namei.c:3989 do_filp_open+0x20c/0x470 fs/namei.c:4016 do_sys_openat2+0x17a/0x1e0 fs/open.c:1428 do_sys_open fs/open.c:1443 [inline] __do_sys_openat fs/open.c:1459 [inline] __se_sys_openat fs/open.c:1454 [inline] __x64_sys_openat+0x175/0x210 fs/open.c:1454 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #2 (&cmd->lock){+.+.}-{4:4}: __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x19b/0xb10 kernel/locking/mutex.c:730 nbd_queue_rq+0xbe/0x1220 drivers/block/nbd.c:1196 blk_mq_dispatch_rq_list+0x443/0x1dc0 block/blk-mq.c:2120 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:170 [inline] blk_mq_do_dispatch_sched block/blk-mq-sched.c:184 [inline] __blk_mq_sched_dispatch_requests+0xcdf/0x1620 block/blk-mq-sched.c:309 blk_mq_sched_dispatch_requests+0xd8/0x1b0 block/blk-mq-sched.c:331 blk_mq_run_hw_queue+0x239/0x670 block/blk-mq.c:2354 blk_mq_dispatch_plug_list block/blk-mq.c:2866 [inline] blk_mq_flush_plug_list+0x673/0x1c60 block/blk-mq.c:2917 __blk_flush_plug+0x2c5/0x4b0 block/blk-core.c:1213 blk_finish_plug block/blk-core.c:1240 [inline] blk_finish_plug block/blk-core.c:1237 [inline] __submit_bio+0x547/0x690 block/blk-core.c:642 __submit_bio_noacct_mq block/blk-core.c:715 [inline] submit_bio_noacct_nocheck+0x698/0xd70 block/blk-core.c:744 submit_bio_noacct+0x50d/0x1ec0 block/blk-core.c:867 submit_bh fs/buffer.c:2819 [inline] block_read_full_folio+0x812/0xa50 fs/buffer.c:2446 filemap_read_folio+0xc6/0x2a0 mm/filemap.c:2390 do_read_cache_folio+0x263/0x5c0 mm/filemap.c:3960 read_mapping_folio include/linux/pagemap.h:1023 [inline] read_part_sector+0xd4/0x310 block/partitions/core.c:722 adfspart_check_ICS+0xa7/0x8c0 block/partitions/acorn.c:360 check_partition block/partitions/core.c:141 [inline] blk_add_partitions block/partitions/core.c:589 [inline] bdev_disk_changed+0x6c6/0x14e0 block/partitions/core.c:693 blkdev_get_whole+0x187/0x290 block/bdev.c:706 bdev_open+0x2c7/0xe20 block/bdev.c:915 blkdev_open+0x272/0x3f0 block/fops.c:652 do_dentry_open+0x735/0x1c40 fs/open.c:956 vfs_open+0x82/0x3f0 fs/open.c:1086 do_open fs/namei.c:3830 [inline] path_openat+0x1e88/0x2d80 fs/namei.c:3989 do_filp_open+0x20c/0x470 fs/namei.c:4016 do_sys_openat2+0x17a/0x1e0 fs/open.c:1428 do_sys_open fs/open.c:1443 [inline] __do_sys_openat fs/open.c:1459 [inline] __se_sys_openat fs/open.c:1454 [inline] __x64_sys_openat+0x175/0x210 fs/open.c:1454 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #1 (set->srcu){.+.+}-{0:0}: srcu_lock_sync include/linux/srcu.h:176 [inline] __synchronize_srcu+0xa9/0x2a0 kernel/rcu/srcutree.c:1418 blk_mq_wait_quiesce_done block/blk-mq.c:293 [inline] blk_mq_wait_quiesce_done block/blk-mq.c:290 [inline] blk_mq_quiesce_queue block/blk-mq.c:313 [inline] blk_mq_quiesce_queue block/blk-mq.c:308 [inline] blk_mq_update_nr_requests+0x288/0x670 block/blk-mq.c:4875 queue_requests_store+0x161/0x210 block/blk-sysfs.c:74 queue_attr_store+0x370/0x510 block/blk-sysfs.c:715 sysfs_kf_write+0x117/0x170 fs/sysfs/file.c:139 kernfs_fop_write_iter+0x33d/0x500 fs/kernfs/file.c:334 new_sync_write fs/read_write.c:586 [inline] vfs_write+0x5ae/0x1150 fs/read_write.c:679 ksys_write+0x12b/0x250 fs/read_write.c:731 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (&q->q_usage_counter(io)#51){++++}-{0:0}: check_prev_add kernel/locking/lockdep.c:3163 [inline] check_prevs_add kernel/locking/lockdep.c:3282 [inline] validate_chain kernel/locking/lockdep.c:3906 [inline] __lock_acquire+0x249e/0x3c40 kernel/locking/lockdep.c:5228 lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5851 bio_queue_enter block/blk.h:77 [inline] blk_mq_submit_bio+0x20db/0x25f0 block/blk-mq.c:3091 __submit_bio+0x3d1/0x690 block/blk-core.c:628 __submit_bio_noacct_mq block/blk-core.c:715 [inline] submit_bio_noacct_nocheck+0x698/0xd70 block/blk-core.c:744 submit_bio_noacct+0x50d/0x1ec0 block/blk-core.c:867 mpage_bio_submit_read fs/mpage.c:75 [inline] mpage_readahead+0x41d/0x590 fs/mpage.c:377 read_pages+0x1a7/0xc60 mm/readahead.c:161 page_cache_ra_unbounded+0x426/0x7d0 mm/readahead.c:298 do_page_cache_ra mm/readahead.c:328 [inline] force_page_cache_ra+0x24b/0x340 mm/readahead.c:357 page_cache_sync_ra+0x158/0xa30 mm/readahead.c:585 filemap_get_pages+0xb62/0x1c30 mm/filemap.c:2580 filemap_read+0x3c5/0xe70 mm/filemap.c:2691 blkdev_read_iter+0x187/0x4b0 block/fops.c:796 new_sync_read fs/read_write.c:484 [inline] vfs_read+0x886/0xbf0 fs/read_write.c:565 ksys_read+0x12b/0x250 fs/read_write.c:708 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f other info that might help us debug this: Chain exists of: &q->q_usage_counter(io)#51 --> &mm->mmap_lock --> mapping.invalidate_lock#2 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- rlock(mapping.invalidate_lock#2); lock(&mm->mmap_lock); lock(mapping.invalidate_lock#2); rlock(&q->q_usage_counter(io)#51); *** DEADLOCK *** 1 lock held by udevd/28721: #0: ffff8880238dabc0 (mapping.invalidate_lock#2){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:932 [inline] #0: ffff8880238dabc0 (mapping.invalidate_lock#2){++++}-{4:4}, at: page_cache_ra_unbounded+0x173/0x7d0 mm/readahead.c:229 stack backtrace: CPU: 0 UID: 0 PID: 28721 Comm: udevd Tainted: G U 6.14.0-rc2-syzkaller-00039-g09fbf3d50205 #0 Tainted: [U]=USER Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_circular_bug+0x490/0x760 kernel/locking/lockdep.c:2076 check_noncircular+0x31a/0x400 kernel/locking/lockdep.c:2208 check_prev_add kernel/locking/lockdep.c:3163 [inline] check_prevs_add kernel/locking/lockdep.c:3282 [inline] validate_chain kernel/locking/lockdep.c:3906 [inline] __lock_acquire+0x249e/0x3c40 kernel/locking/lockdep.c:5228 lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5851 bio_queue_enter block/blk.h:77 [inline] blk_mq_submit_bio+0x20db/0x25f0 block/blk-mq.c:3091 __submit_bio+0x3d1/0x690 block/blk-core.c:628 __submit_bio_noacct_mq block/blk-core.c:715 [inline] submit_bio_noacct_nocheck+0x698/0xd70 block/blk-core.c:744 submit_bio_noacct+0x50d/0x1ec0 block/blk-core.c:867 mpage_bio_submit_read fs/mpage.c:75 [inline] mpage_readahead+0x41d/0x590 fs/mpage.c:377 read_pages+0x1a7/0xc60 mm/readahead.c:161 page_cache_ra_unbounded+0x426/0x7d0 mm/readahead.c:298 do_page_cache_ra mm/readahead.c:328 [inline] force_page_cache_ra+0x24b/0x340 mm/readahead.c:357 page_cache_sync_ra+0x158/0xa30 mm/readahead.c:585 filemap_get_pages+0xb62/0x1c30 mm/filemap.c:2580 filemap_read+0x3c5/0xe70 mm/filemap.c:2691 blkdev_read_iter+0x187/0x4b0 block/fops.c:796 new_sync_read fs/read_write.c:484 [inline] vfs_read+0x886/0xbf0 fs/read_write.c:565 ksys_read+0x12b/0x250 fs/read_write.c:708 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f83c7d16b6a Code: 00 3d 00 00 41 00 75 0d 50 48 8d 3d 2d 08 0a 00 e8 ea 7d 01 00 31 c0 e9 07 ff ff ff 64 8b 04 25 18 00 00 00 85 c0 75 1b 0f 05 <48> 3d 00 f0 ff ff 76 6c 48 8b 15 8f a2 0d 00 f7 d8 64 89 02 48 83 RSP: 002b:00007ffc5d8f02f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00001fffffff0000 RCX: 00007f83c7d16b6a RDX: 0000000000000040 RSI: 0000562f292b8048 RDI: 0000000000000009 RBP: 0000000000000040 R08: 0000562f292b8020 R09: 00007f83c7df1b60 R10: 0000000000000007 R11: 0000000000000246 R12: 0000562f292b8020 R13: 0000562f292b8038 R14: 0000562f292c8798 R15: 0000562f292c8740