Hello, syzbot found the following issue on: HEAD commit: fcc79e1714e8 Merge tag 'net-next-6.13' of git://git.kernel.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=12b1d930580000 kernel config: https://syzkaller.appspot.com/x/.config?x=e78c767e2e984329 dashboard link: https://syzkaller.appspot.com/bug?extid=f562f0286b285b26b0c2 compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/53fb758f6bdd/disk-fcc79e17.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/b19fc1447a6b/vmlinux-fcc79e17.xz kernel image: https://storage.googleapis.com/syzbot-assets/b2c341b38155/bzImage-fcc79e17.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+f562f0286b285b26b0c2@xxxxxxxxxxxxxxxxxxxxxxxxx ====================================================== WARNING: possible circular locking dependency detected 6.12.0-syzkaller-05480-gfcc79e1714e8 #0 Not tainted ------------------------------------------------------ syz.5.2508/16156 is trying to acquire lock: ffff888027a72cf8 (&q->sysfs_lock){+.+.}-{4:4}, at: blk_register_queue+0x145/0x460 block/blk-sysfs.c:772 but task is already holding lock: ffff888027a72d88 (&q->sysfs_dir_lock){+.+.}-{4:4}, at: blk_register_queue+0x67/0x460 block/blk-sysfs.c:761 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #6 (&q->sysfs_dir_lock){+.+.}-{4:4}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x1ac/0xee0 kernel/locking/mutex.c:735 blk_mq_sysfs_unregister_hctxs+0xaa/0x300 block/blk-mq-sysfs.c:278 __blk_mq_update_nr_hw_queues block/blk-mq.c:4930 [inline] blk_mq_update_nr_hw_queues+0x6cc/0x1ae0 block/blk-mq.c:4985 nbd_start_device+0x16c/0xaa0 drivers/block/nbd.c:1413 nbd_start_device_ioctl drivers/block/nbd.c:1464 [inline] __nbd_ioctl drivers/block/nbd.c:1539 [inline] nbd_ioctl+0x5dc/0xf40 drivers/block/nbd.c:1579 blkdev_ioctl+0x57d/0x6a0 block/ioctl.c:693 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl+0xf5/0x170 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #5 (&q->q_usage_counter(io)#49){++++}-{0:0}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 bio_queue_enter block/blk.h:75 [inline] blk_mq_submit_bio+0x1536/0x23a0 block/blk-mq.c:3092 __submit_bio+0x2c6/0x560 block/blk-core.c:629 __submit_bio_noacct_mq block/blk-core.c:710 [inline] submit_bio_noacct_nocheck+0x4d3/0xe30 block/blk-core.c:739 submit_bh fs/buffer.c:2825 [inline] block_read_full_folio+0x93b/0xcd0 fs/buffer.c:2452 filemap_read_folio+0x14b/0x630 mm/filemap.c:2367 filemap_update_page mm/filemap.c:2451 [inline] filemap_get_pages+0x17af/0x2540 mm/filemap.c:2572 filemap_read+0x45c/0xf50 mm/filemap.c:2647 blkdev_read_iter+0x2d8/0x430 block/fops.c:767 new_sync_read fs/read_write.c:484 [inline] vfs_read+0x991/0xb70 fs/read_write.c:565 ksys_read+0x18f/0x2b0 fs/read_write.c:708 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #4 (mapping.invalidate_lock#2){.+.+}-{4:4}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 down_read+0xb1/0xa40 kernel/locking/rwsem.c:1524 filemap_invalidate_lock_shared include/linux/fs.h:873 [inline] filemap_fault+0x6e8/0x1950 mm/filemap.c:3333 __do_fault+0x135/0x460 mm/memory.c:4882 do_read_fault mm/memory.c:5297 [inline] do_fault mm/memory.c:5431 [inline] do_pte_missing mm/memory.c:3965 [inline] handle_pte_fault+0x2d1c/0x6820 mm/memory.c:5766 __handle_mm_fault mm/memory.c:5909 [inline] handle_mm_fault+0x1053/0x1ad0 mm/memory.c:6077 do_user_addr_fault arch/x86/mm/fault.c:1338 [inline] handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x459/0x8c0 arch/x86/mm/fault.c:1539 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 -> #3 (&vma->vm_lock->lock){++++}-{4:4}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 down_write+0x99/0x220 kernel/locking/rwsem.c:1577 vma_start_write include/linux/mm.h:769 [inline] vma_link+0x28c/0x500 mm/vma.c:1600 insert_vm_struct+0x2f7/0x410 mm/mmap.c:1995 __bprm_mm_init fs/exec.c:289 [inline] bprm_mm_init fs/exec.c:393 [inline] alloc_bprm+0x8f5/0xe20 fs/exec.c:1548 kernel_execve+0x99/0xa50 fs/exec.c:1977 try_to_run_init_process init/main.c:1394 [inline] kernel_init+0xed/0x2b0 init/main.c:1522 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 -> #2 (&mm->mmap_lock){++++}-{4:4}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __might_fault+0xc6/0x120 mm/memory.c:6716 _inline_copy_from_user include/linux/uaccess.h:162 [inline] _copy_from_user+0x2a/0xc0 lib/usercopy.c:18 copy_from_user include/linux/uaccess.h:212 [inline] __blk_trace_setup kernel/trace/blktrace.c:626 [inline] blk_trace_ioctl+0x1ad/0x9a0 kernel/trace/blktrace.c:740 blkdev_ioctl+0x40c/0x6a0 block/ioctl.c:682 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl+0xf5/0x170 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #1 (&q->debugfs_mutex){+.+.}-{4:4}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x1ac/0xee0 kernel/locking/mutex.c:735 blk_register_queue+0x156/0x460 block/blk-sysfs.c:774 add_disk_fwnode+0x648/0xf80 block/genhd.c:493 add_disk include/linux/blkdev.h:751 [inline] brd_alloc+0x547/0x790 drivers/block/brd.c:399 brd_init+0x126/0x1b0 drivers/block/brd.c:479 do_one_initcall+0x248/0x880 init/main.c:1266 do_initcall_level+0x157/0x210 init/main.c:1328 do_initcalls+0x3f/0x80 init/main.c:1344 kernel_init_freeable+0x435/0x5d0 init/main.c:1577 kernel_init+0x1d/0x2b0 init/main.c:1466 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 -> #0 (&q->sysfs_lock){+.+.}-{4:4}: check_prev_add kernel/locking/lockdep.c:3161 [inline] check_prevs_add kernel/locking/lockdep.c:3280 [inline] validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904 __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5226 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x1ac/0xee0 kernel/locking/mutex.c:735 blk_register_queue+0x145/0x460 block/blk-sysfs.c:772 add_disk_fwnode+0x648/0xf80 block/genhd.c:493 add_disk include/linux/blkdev.h:751 [inline] md_alloc+0x78c/0xde0 drivers/md/md.c:5909 md_alloc_and_put+0x18/0x1c0 drivers/md/md.c:5944 blk_request_module+0x18d/0x1b0 block/genhd.c:812 blkdev_get_no_open+0x36/0xc0 block/bdev.c:784 bdev_file_open_by_dev+0x99/0x220 block/bdev.c:1005 swsusp_check+0x5b/0x3f0 kernel/power/swap.c:1569 software_resume+0x4f/0x3d0 kernel/power/hibernate.c:990 resume_store+0x3fe/0x710 kernel/power/hibernate.c:1268 kernfs_fop_write_iter+0x3a0/0x500 fs/kernfs/file.c:334 new_sync_write fs/read_write.c:586 [inline] vfs_write+0xaeb/0xd30 fs/read_write.c:679 ksys_write+0x18f/0x2b0 fs/read_write.c:731 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 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->sysfs_lock --> &q->q_usage_counter(io)#49 --> &q->sysfs_dir_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&q->sysfs_dir_lock); lock(&q->q_usage_counter(io)#49); lock(&q->sysfs_dir_lock); lock(&q->sysfs_lock); *** DEADLOCK *** 8 locks held by syz.5.2508/16156: #0: ffff88806cc8e478 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x254/0x320 fs/file.c:1191 #1: ffff8880353fc420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2964 [inline] #1: ffff8880353fc420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x225/0xd30 fs/read_write.c:675 #2: ffff88807af3b088 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1ea/0x500 fs/kernfs/file.c:325 #3: ffff88801d6ad3c8 (kn->active#75){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20e/0x500 fs/kernfs/file.c:326 #4: ffffffff8e7ef648 (system_transition_mutex){+.+.}-{4:4}, at: software_resume+0x45/0x3d0 kernel/power/hibernate.c:989 #5: ffffffff8f064aa8 (major_names_lock){+.+.}-{4:4}, at: blk_request_module+0x33/0x1b0 block/genhd.c:809 #6: ffffffff8f995228 (disks_mutex){+.+.}-{4:4}, at: md_alloc+0x36/0xde0 drivers/md/md.c:5857 #7: ffff888027a72d88 (&q->sysfs_dir_lock){+.+.}-{4:4}, at: blk_register_queue+0x67/0x460 block/blk-sysfs.c:761 stack backtrace: CPU: 1 UID: 0 PID: 16156 Comm: syz.5.2508 Not tainted 6.12.0-syzkaller-05480-gfcc79e1714e8 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024 Call Trace: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_circular_bug+0x13a/0x1b0 kernel/locking/lockdep.c:2074 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2206 check_prev_add kernel/locking/lockdep.c:3161 [inline] check_prevs_add kernel/locking/lockdep.c:3280 [inline] validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904 __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5226 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x1ac/0xee0 kernel/locking/mutex.c:735 blk_register_queue+0x145/0x460 block/blk-sysfs.c:772 add_disk_fwnode+0x648/0xf80 block/genhd.c:493 add_disk include/linux/blkdev.h:751 [inline] md_alloc+0x78c/0xde0 drivers/md/md.c:5909 md_alloc_and_put+0x18/0x1c0 drivers/md/md.c:5944 blk_request_module+0x18d/0x1b0 block/genhd.c:812 blkdev_get_no_open+0x36/0xc0 block/bdev.c:784 bdev_file_open_by_dev+0x99/0x220 block/bdev.c:1005 swsusp_check+0x5b/0x3f0 kernel/power/swap.c:1569 software_resume+0x4f/0x3d0 kernel/power/hibernate.c:990 resume_store+0x3fe/0x710 kernel/power/hibernate.c:1268 kernfs_fop_write_iter+0x3a0/0x500 fs/kernfs/file.c:334 new_sync_write fs/read_write.c:586 [inline] vfs_write+0xaeb/0xd30 fs/read_write.c:679 ksys_write+0x18f/0x2b0 fs/read_write.c:731 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe74157e819 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fe7423fb038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fe741736160 RCX: 00007fe74157e819 RDX: 0000000000000012 RSI: 0000000020000040 RDI: 0000000000000009 RBP: 00007fe7415f175e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fe741736160 R15: 00007ffd646be318 </TASK> block device autoloading is deprecated and will be removed. syz.5.2508: attempt to access beyond end of device md0: rw=2048, sector=0, nr_sectors = 8 limit=0 PM: Image not found (code -5) --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup
