syzbot

======================================================
WARNING: possible circular locking dependency detected
6.13.0-syzkaller #0 Not tainted
------------------------------------------------------
syz.5.3188/20045 is trying to acquire lock:
ffff888024f22330 (&q->sysfs_lock){+.+.}-{4:4}, at: queue_attr_store+0xe2/0x170 block/blk-sysfs.c:710

but task is already holding lock:
ffff888024f21e00 (&q->q_usage_counter(io)#4){++++}-{0:0}, at: queue_attr_store+0xd8/0x170 block/blk-sysfs.c:709

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #4 (&q->q_usage_counter(io)#4){++++}-{0:0}:
       bio_queue_enter block/blk.h:75 [inline]
       __submit_bio+0x49c/0x540 block/blk-core.c:630
       __submit_bio_noacct block/blk-core.c:678 [inline]
       submit_bio_noacct_nocheck+0x892/0xd70 block/blk-core.c:741
       submit_bio_noacct+0x93a/0x1e20 block/blk-core.c:868
       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:2357
       filemap_update_page mm/filemap.c:2441 [inline]
       filemap_get_pages+0x155f/0x1be0 mm/filemap.c:2562
       filemap_splice_read+0x5cc/0xd00 mm/filemap.c:2913
       do_splice_read fs/splice.c:985 [inline]
       do_splice_read+0x282/0x370 fs/splice.c:959
       splice_file_to_pipe+0x109/0x120 fs/splice.c:1295
       do_sendfile+0x3fd/0xe30 fs/read_write.c:1369
       __do_sys_sendfile64 fs/read_write.c:1424 [inline]
       __se_sys_sendfile64 fs/read_write.c:1410 [inline]
       __x64_sys_sendfile64+0x1da/0x220 fs/read_write.c:1410
       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 (mapping.invalidate_lock#2){++++}-{4:4}:
       down_read+0x9a/0x330 kernel/locking/rwsem.c:1524
       filemap_invalidate_lock_shared include/linux/fs.h:873 [inline]
       filemap_fault+0x2e0/0x2820 mm/filemap.c:3323
       __do_fault+0x10a/0x490 mm/memory.c:4907
       do_read_fault mm/memory.c:5322 [inline]
       do_fault mm/memory.c:5456 [inline]
       do_pte_missing+0xebd/0x3e00 mm/memory.c:3979
       handle_pte_fault mm/memory.c:5801 [inline]
       __handle_mm_fault+0x103c/0x2a40 mm/memory.c:5944
       handle_mm_fault+0x3fa/0xaa0 mm/memory.c:6112
       do_user_addr_fault+0x7a3/0x13f0 arch/x86/mm/fault.c:1389
       handle_page_fault arch/x86/mm/fault.c:1481 [inline]
       exc_page_fault+0x5c/0xc0 arch/x86/mm/fault.c:1539
       asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
       fault_in_readable+0x160/0x200 mm/gup.c:2244
       fault_in_iov_iter_readable+0x101/0x2c0 lib/iov_iter.c:94
       iomap_write_iter fs/iomap/buffered-io.c:950 [inline]
       iomap_file_buffered_write+0x3e2/0xc70 fs/iomap/buffered-io.c:1039
       blkdev_buffered_write block/fops.c:665 [inline]
       blkdev_write_iter+0x545/0xd40 block/fops.c:721
       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

-> #2 (&mm->mmap_lock){++++}-{4:4}:
       __might_fault mm/memory.c:6751 [inline]
       __might_fault+0x11b/0x190 mm/memory.c:6744
       _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]
       __blk_trace_setup+0xa8/0x180 kernel/trace/blktrace.c:626
       blk_trace_setup+0x47/0x70 kernel/trace/blktrace.c:648
       sg_ioctl_common drivers/scsi/sg.c:1114 [inline]
       sg_ioctl+0x7a3/0x26b0 drivers/scsi/sg.c:1156
       vfs_ioctl fs/ioctl.c:51 [inline]
       __do_sys_ioctl fs/ioctl.c:906 [inline]
       __se_sys_ioctl fs/ioctl.c:892 [inline]
       __x64_sys_ioctl+0x190/0x200 fs/ioctl.c:892
       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 (&q->debugfs_mutex){+.+.}-{4:4}:
       __mutex_lock_common kernel/locking/mutex.c:585 [inline]
       __mutex_lock+0x19b/0xa60 kernel/locking/mutex.c:735
       blk_register_queue+0x13c/0x4f0 block/blk-sysfs.c:774
       add_disk_fwnode+0x785/0x1300 block/genhd.c:493
       add_disk include/linux/blkdev.h:753 [inline]
       brd_alloc.isra.0+0x50a/0x7c0 drivers/block/brd.c:401
       brd_init+0x12b/0x1d0 drivers/block/brd.c:481
       do_one_initcall+0x128/0x630 init/main.c:1266
       do_initcall_level init/main.c:1328 [inline]
       do_initcalls init/main.c:1344 [inline]
       do_basic_setup init/main.c:1363 [inline]
       kernel_init_freeable+0x58f/0x8b0 init/main.c:1577
       kernel_init+0x1c/0x2b0 init/main.c:1466
       ret_from_fork+0x45/0x80 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 kernel/locking/lockdep.c:3904 [inline]
       __lock_acquire+0x249e/0x3c40 kernel/locking/lockdep.c:5226
       lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849
       __mutex_lock_common kernel/locking/mutex.c:585 [inline]
       __mutex_lock+0x19b/0xa60 kernel/locking/mutex.c:735
       queue_attr_store+0xe2/0x170 block/blk-sysfs.c:710
       sysfs_kf_write+0x117/0x170 fs/sysfs/file.c:139
       kernfs_fop_write_iter+0x33d/0x500 fs/kernfs/file.c:334
       iter_file_splice_write+0x90f/0x10b0 fs/splice.c:743
       do_splice_from fs/splice.c:941 [inline]
       direct_splice_actor+0x18f/0x6c0 fs/splice.c:1164
       splice_direct_to_actor+0x346/0xa40 fs/splice.c:1108
       do_splice_direct_actor fs/splice.c:1207 [inline]
       do_splice_direct+0x178/0x250 fs/splice.c:1233
       do_sendfile+0xaed/0xe30 fs/read_write.c:1363
       __do_sys_sendfile64 fs/read_write.c:1424 [inline]
       __se_sys_sendfile64 fs/read_write.c:1410 [inline]
       __x64_sys_sendfile64+0x1da/0x220 fs/read_write.c:1410
       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->sysfs_lock --> mapping.invalidate_lock#2 --> &q->q_usage_counter(io)#4

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&q->q_usage_counter(io)#4);
                               lock(mapping.invalidate_lock#2);
                               lock(&q->q_usage_counter(io)#4);
  lock(&q->sysfs_lock);

 *** DEADLOCK ***

5 locks held by syz.5.3188/20045:
 #0: ffff88803531a420 (sb_writers#8){.+.+}-{0:0}, at: splice_direct_to_actor+0x346/0xa40 fs/splice.c:1108
 #1: ffff888040d6d488 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x27b/0x500 fs/kernfs/file.c:325
 #2: ffff88801ffcae18 (kn->active#90){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x29e/0x500 fs/kernfs/file.c:326
 #3: ffff888024f21e00 (&q->q_usage_counter(io)#4){++++}-{0:0}, at: queue_attr_store+0xd8/0x170 block/blk-sysfs.c:709
 #4: ffff888024f21e38 (&q->q_usage_counter(queue)#55){+.+.}-{0:0}, at: queue_attr_store+0xd8/0x170 block/blk-sysfs.c:709

stack backtrace:
CPU: 1 UID: 0 PID: 20045 Comm: syz.5.3188 Not tainted 6.13.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 print_circular_bug+0x41c/0x610 kernel/locking/lockdep.c:2074
 check_noncircular+0x31a/0x400 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 kernel/locking/lockdep.c:3904 [inline]
 __lock_acquire+0x249e/0x3c40 kernel/locking/lockdep.c:5226
 lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849
 __mutex_lock_common kernel/locking/mutex.c:585 [inline]
 __mutex_lock+0x19b/0xa60 kernel/locking/mutex.c:735
 queue_attr_store+0xe2/0x170 block/blk-sysfs.c:710
 sysfs_kf_write+0x117/0x170 fs/sysfs/file.c:139
 kernfs_fop_write_iter+0x33d/0x500 fs/kernfs/file.c:334
 iter_file_splice_write+0x90f/0x10b0 fs/splice.c:743
 do_splice_from fs/splice.c:941 [inline]
 direct_splice_actor+0x18f/0x6c0 fs/splice.c:1164
 splice_direct_to_actor+0x346/0xa40 fs/splice.c:1108
 do_splice_direct_actor fs/splice.c:1207 [inline]
 do_splice_direct+0x178/0x250 fs/splice.c:1233
 do_sendfile+0xaed/0xe30 fs/read_write.c:1363
 __do_sys_sendfile64 fs/read_write.c:1424 [inline]
 __se_sys_sendfile64 fs/read_write.c:1410 [inline]
 __x64_sys_sendfile64+0x1da/0x220 fs/read_write.c:1410
 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: 0033:0x7fbe7f985d29
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:00007fbe80804038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007fbe7fb75fa0 RCX: 00007fbe7f985d29
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 0000000000000009
RBP: 00007fbe7fa01b08 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000006 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fbe7fb75fa0 R15: 00007ffdd67cd5b8
 </TASK>