====================================================== WARNING: possible circular locking dependency detected 6.6.102-syzkaller #0 Not tainted ------------------------------------------------------ syz.1.673/9024 is trying to acquire lock: ffff88807b86cae8 (&sdp->sd_quota_mutex){+.+.}-{3:3}, at: do_qc+0xaf/0x670 fs/gfs2/quota.c:689 but task is already holding lock: ffff8880584a05e8 (&ip->i_rw_mutex){++++}-{3:3}, at: sweep_bh_for_rgrps fs/gfs2/bmap.c:1526 [inline] ffff8880584a05e8 (&ip->i_rw_mutex){++++}-{3:3}, at: punch_hole+0x1c7d/0x2d70 fs/gfs2/bmap.c:1850 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&ip->i_rw_mutex){++++}-{3:3}: down_read+0x46/0x2e0 kernel/locking/rwsem.c:1520 __gfs2_iomap_get+0x159/0x13f0 fs/gfs2/bmap.c:856 gfs2_iomap_get+0xc5/0x120 fs/gfs2/bmap.c:1410 bh_get+0x225/0x710 fs/gfs2/quota.c:401 qd_fish fs/gfs2/quota.c:496 [inline] gfs2_quota_sync+0x33a/0x5a0 fs/gfs2/quota.c:1335 gfs2_sync_fs+0x4c/0xb0 fs/gfs2/super.c:670 sync_filesystem+0xea/0x220 fs/sync.c:56 generic_shutdown_super+0x6f/0x2b0 fs/super.c:666 kill_block_super+0x44/0x90 fs/super.c:1660 deactivate_locked_super+0x97/0x100 fs/super.c:481 cleanup_mnt+0x429/0x4c0 fs/namespace.c:1250 task_work_run+0x1ce/0x250 kernel/task_work.c:239 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302 do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 -> #0 (&sdp->sd_quota_mutex){+.+.}-{3:3}: check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3869 [inline] __lock_acquire+0x2ddb/0x7c80 kernel/locking/lockdep.c:5137 lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x129/0xcc0 kernel/locking/mutex.c:747 do_qc+0xaf/0x670 fs/gfs2/quota.c:689 gfs2_quota_change+0x2b9/0x800 fs/gfs2/quota.c:1289 punch_hole+0x280c/0x2d70 fs/gfs2/bmap.c:1951 gfs2_iomap_end+0x4f6/0x6b0 fs/gfs2/bmap.c:1171 iomap_iter+0x21e/0xec0 fs/iomap/iter.c:79 iomap_file_buffered_write+0xb8b/0xd10 fs/iomap/buffered-io.c:974 gfs2_file_buffered_write+0x4bd/0x820 fs/gfs2/file.c:1060 gfs2_file_write_iter+0x427/0xe10 fs/gfs2/file.c:1158 call_write_iter include/linux/fs.h:2018 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x43b/0x940 fs/read_write.c:584 ksys_write+0x147/0x250 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&ip->i_rw_mutex); lock(&sdp->sd_quota_mutex); lock(&ip->i_rw_mutex); lock(&sdp->sd_quota_mutex); *** DEADLOCK *** 6 locks held by syz.1.673/9024: #0: ffff88802ea68fc8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2a3/0x330 fs/file.c:1042 #1: ffff888020bde418 (sb_writers#30){.+.+}-{0:0}, at: vfs_write+0x20e/0x940 fs/read_write.c:580 #2: ffff8880584a0160 (&sb->s_type->i_mutex_key#35){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline] #2: ffff8880584a0160 (&sb->s_type->i_mutex_key#35){+.+.}-{3:3}, at: gfs2_file_write_iter+0x304/0xe10 fs/gfs2/file.c:1115 #3: ffff888020bde608 (sb_internal#7){.+.+}-{0:0}, at: gfs2_trans_begin+0x6f/0xe0 fs/gfs2/trans.c:118 #4: ffff88807b86d060 (&sdp->sd_log_flush_lock){++++}-{3:3}, at: __gfs2_trans_begin+0x511/0x880 fs/gfs2/trans.c:87 #5: ffff8880584a05e8 (&ip->i_rw_mutex){++++}-{3:3}, at: sweep_bh_for_rgrps fs/gfs2/bmap.c:1526 [inline] #5: ffff8880584a05e8 (&ip->i_rw_mutex){++++}-{3:3}, at: punch_hole+0x1c7d/0x2d70 fs/gfs2/bmap.c:1850 stack backtrace: CPU: 0 PID: 9024 Comm: syz.1.673 Not tainted 6.6.102-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106 check_noncircular+0x2bd/0x3c0 kernel/locking/lockdep.c:2187 check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3869 [inline] __lock_acquire+0x2ddb/0x7c80 kernel/locking/lockdep.c:5137 lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x129/0xcc0 kernel/locking/mutex.c:747 do_qc+0xaf/0x670 fs/gfs2/quota.c:689 gfs2_quota_change+0x2b9/0x800 fs/gfs2/quota.c:1289 punch_hole+0x280c/0x2d70 fs/gfs2/bmap.c:1951 gfs2_iomap_end+0x4f6/0x6b0 fs/gfs2/bmap.c:1171 iomap_iter+0x21e/0xec0 fs/iomap/iter.c:79 iomap_file_buffered_write+0xb8b/0xd10 fs/iomap/buffered-io.c:974 gfs2_file_buffered_write+0x4bd/0x820 fs/gfs2/file.c:1060 gfs2_file_write_iter+0x427/0xe10 fs/gfs2/file.c:1158 call_write_iter include/linux/fs.h:2018 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x43b/0x940 fs/read_write.c:584 ksys_write+0x147/0x250 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f1be8d8ebe9 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:00007f1be9bdc038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f1be8fb6090 RCX: 00007f1be8d8ebe9 RDX: 000000000208e24b RSI: 0000200000000040 RDI: 0000000000000008 RBP: 00007f1be8e11e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f1be8fb6128 R14: 00007f1be8fb6090 R15: 00007fff3979fbb8