====================================================== WARNING: possible circular locking dependency detected 6.13.0-rc7-syzkaller-00191-gfda5e3f28400 #0 Not tainted ------------------------------------------------------ syz.3.245/6947 is trying to acquire lock: ffff888028996360 (&mm->mmap_lock){++++}-{4:4}, at: __might_fault+0xaa/0x120 mm/memory.c:6751 but task is already holding lock: ffff8880252feae8 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0xdd/0x9a0 kernel/trace/blktrace.c:735 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #6 (&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_mq_init_sched+0x3fa/0x830 block/blk-mq-sched.c:473 elevator_init_mq+0x20e/0x320 block/elevator.c:610 add_disk_fwnode+0x10d/0xf80 block/genhd.c:413 sd_probe+0xba6/0x1100 drivers/scsi/sd.c:4024 really_probe+0x2ba/0xad0 drivers/base/dd.c:658 __driver_probe_device+0x1a2/0x390 drivers/base/dd.c:800 driver_probe_device+0x50/0x430 drivers/base/dd.c:830 __device_attach_driver+0x2d6/0x530 drivers/base/dd.c:958 bus_for_each_drv+0x250/0x2e0 drivers/base/bus.c:459 __device_attach_async_helper+0x22d/0x300 drivers/base/dd.c:987 async_run_entry_fn+0xaa/0x420 kernel/async.c:129 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xa68/0x1840 kernel/workqueue.c:3317 worker_thread+0x870/0xd30 kernel/workqueue.c:3398 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 -> #5 (&q->q_usage_counter(queue)#50){++++}-{0:0}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 blk_queue_enter+0xe1/0x600 block/blk-core.c:328 blk_mq_alloc_request+0x4fa/0xaa0 block/blk-mq.c:652 scsi_alloc_request drivers/scsi/scsi_lib.c:1225 [inline] scsi_execute_cmd+0x16c/0x10e0 drivers/scsi/scsi_lib.c:307 read_capacity_16+0x2b4/0x1450 drivers/scsi/sd.c:2655 sd_read_capacity drivers/scsi/sd.c:2824 [inline] sd_revalidate_disk+0x1013/0xbce0 drivers/scsi/sd.c:3734 sd_probe+0x9fa/0x1100 drivers/scsi/sd.c:4010 really_probe+0x2ba/0xad0 drivers/base/dd.c:658 __driver_probe_device+0x1a2/0x390 drivers/base/dd.c:800 driver_probe_device+0x50/0x430 drivers/base/dd.c:830 __device_attach_driver+0x2d6/0x530 drivers/base/dd.c:958 bus_for_each_drv+0x250/0x2e0 drivers/base/bus.c:459 __device_attach_async_helper+0x22d/0x300 drivers/base/dd.c:987 async_run_entry_fn+0xaa/0x420 kernel/async.c:129 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xa68/0x1840 kernel/workqueue.c:3317 worker_thread+0x870/0xd30 kernel/workqueue.c:3398 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 -> #4 (&q->limits_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 queue_limits_start_update include/linux/blkdev.h:947 [inline] loop_reconfigure_limits+0x43f/0x900 drivers/block/loop.c:998 loop_set_block_size drivers/block/loop.c:1473 [inline] lo_simple_ioctl drivers/block/loop.c:1496 [inline] lo_ioctl+0x1351/0x1f50 drivers/block/loop.c:1559 blkdev_ioctl+0x57f/0x6a0 block/ioctl.c:693 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl+0xf7/0x170 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 -> #3 (&q->q_usage_counter(io)#23){++++}-{0:0}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 bio_queue_enter block/blk.h:75 [inline] blk_mq_submit_bio+0x1536/0x2390 block/blk-mq.c:3090 __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 ext4_read_block_bitmap_nowait+0x7c5/0xa80 fs/ext4/balloc.c:551 ext4_mb_prefetch+0x240/0x380 fs/ext4/mballoc.c:2749 ext4_mb_regular_allocator+0xb44/0x3bb0 fs/ext4/mballoc.c:2898 ext4_mb_new_blocks+0x10a8/0x4e00 fs/ext4/mballoc.c:6217 ext4_ext_map_blocks+0x1be0/0x7d30 fs/ext4/extents.c:4379 ext4_map_create_blocks fs/ext4/inode.c:516 [inline] ext4_map_blocks+0x8bf/0x1990 fs/ext4/inode.c:702 ext4_getblk+0x1fa/0x880 fs/ext4/inode.c:849 ext4_bread+0x2e/0x180 fs/ext4/inode.c:912 ext4_append+0x327/0x5c0 fs/ext4/namei.c:83 ext4_init_new_dir+0x33e/0xa30 fs/ext4/namei.c:2988 ext4_mkdir+0x4f7/0xcf0 fs/ext4/namei.c:3034 vfs_mkdir+0x2fb/0x4f0 fs/namei.c:4311 do_mkdirat+0x264/0x3a0 fs/namei.c:4334 __do_sys_mkdirat fs/namei.c:4349 [inline] __se_sys_mkdirat fs/namei.c:4347 [inline] __x64_sys_mkdirat+0x87/0xa0 fs/namei.c:4347 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 -> #2 (&ei->i_data_sem){++++}-{4:4}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 down_write+0x99/0x220 kernel/locking/rwsem.c:1577 ext4_truncate+0x994/0x11c0 fs/ext4/inode.c:4212 ext4_setattr+0x113a/0x1da0 fs/ext4/inode.c:5541 notify_change+0xbcc/0xe90 fs/attr.c:552 do_truncate fs/open.c:65 [inline] do_ftruncate+0x462/0x580 fs/open.c:181 do_sys_ftruncate fs/open.c:196 [inline] __do_sys_ftruncate fs/open.c:201 [inline] __se_sys_ftruncate fs/open.c:199 [inline] __x64_sys_ftruncate+0x94/0xf0 fs/open.c:199 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 (jbd2_handle){++++}-{0:0}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 start_this_handle+0x1eb4/0x2110 fs/jbd2/transaction.c:448 jbd2__journal_start+0x2da/0x5d0 fs/jbd2/transaction.c:505 __ext4_journal_start_sb+0x239/0x600 fs/ext4/ext4_jbd2.c:112 __ext4_journal_start fs/ext4/ext4_jbd2.h:326 [inline] ext4_dirty_inode+0x92/0x110 fs/ext4/inode.c:6038 __mark_inode_dirty+0x2f0/0xe90 fs/fs-writeback.c:2515 generic_update_time fs/inode.c:2112 [inline] inode_update_time fs/inode.c:2125 [inline] touch_atime+0x413/0x690 fs/inode.c:2197 file_accessed include/linux/fs.h:2539 [inline] ext4_file_mmap+0x18c/0x540 fs/ext4/file.c:816 call_mmap include/linux/fs.h:2183 [inline] mmap_file mm/internal.h:124 [inline] __mmap_new_file_vma mm/vma.c:2291 [inline] __mmap_new_vma mm/vma.c:2355 [inline] __mmap_region+0x2250/0x2d30 mm/vma.c:2456 mmap_region+0x226/0x2c0 mm/mmap.c:1352 do_mmap+0x97a/0x10d0 mm/mmap.c:500 vm_mmap_pgoff+0x1dd/0x3d0 mm/util.c:575 ksys_mmap_pgoff+0x4eb/0x720 mm/mmap.c:546 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 -> #0 (&mm->mmap_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 __might_fault+0xc6/0x120 mm/memory.c:6751 _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+0xf7/0x170 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 other info that might help us debug this: Chain exists of: &mm->mmap_lock --> &q->q_usage_counter(queue)#50 --> &q->debugfs_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&q->debugfs_mutex); lock(&q->q_usage_counter(queue)#50); lock(&q->debugfs_mutex); rlock(&mm->mmap_lock); *** DEADLOCK *** 1 lock held by syz.3.245/6947: #0: ffff8880252feae8 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0xdd/0x9a0 kernel/trace/blktrace.c:735 stack backtrace: CPU: 0 UID: 0 PID: 6947 Comm: syz.3.245 Not tainted 6.13.0-rc7-syzkaller-00191-gfda5e3f28400 #0 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+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 __might_fault+0xc6/0x120 mm/memory.c:6751 _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+0xf7/0x170 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 RIP: 0033:0x7f9516985d29 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:00007f95177ac038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f9516b75fa0 RCX: 00007f9516985d29 RDX: 0000000000000000 RSI: 00000000c0481273 RDI: 0000000000000005 RBP: 00007f9516a01b08 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f9516b75fa0 R15: 00007ffe3a8ad418