====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.3.437/6145 is trying to acquire lock: ffff888029d40ae0 (&sdp->sd_quota_mutex){+.+.}-{3:3}, at: do_qc+0xca/0x730 fs/gfs2/quota.c:682 but task is already holding lock: ffff888056294fd0 (&ip->i_rw_mutex){++++}-{3:3}, at: sweep_bh_for_rgrps fs/gfs2/bmap.c:1529 [inline] ffff888056294fd0 (&ip->i_rw_mutex){++++}-{3:3}, at: punch_hole+0x24b8/0x3760 fs/gfs2/bmap.c:1854 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+0x42/0x2d0 kernel/locking/rwsem.c:1520 __gfs2_iomap_get+0x15b/0x1400 fs/gfs2/bmap.c:862 gfs2_iomap_get+0xeb/0x170 fs/gfs2/bmap.c:1413 bh_get+0x26d/0x780 fs/gfs2/quota.c:385 qdsb_get+0x21c/0x3c0 fs/gfs2/quota.c:522 gfs2_quota_hold+0x194/0x5d0 fs/gfs2/quota.c:608 punch_hole+0xda8/0x3760 fs/gfs2/bmap.c:1815 gfs2_iomap_end+0x5e1/0x7a0 fs/gfs2/bmap.c:1174 iomap_iter+0x21a/0x1040 fs/iomap/iter.c:79 iomap_file_buffered_write+0x78b/0x8f0 fs/iomap/buffered-io.c:846 gfs2_file_buffered_write+0x4fe/0x880 fs/gfs2/file.c:1057 gfs2_file_write_iter+0x486/0xe90 fs/gfs2/file.c:1158 call_write_iter include/linux/fs.h:2265 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x4b1/0xa30 fs/read_write.c:584 ksys_write+0x14c/0x250 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 -> #0 (&sdp->sd_quota_mutex){+.+.}-{3:3}: check_prev_add kernel/locking/lockdep.c:3090 [inline] check_prevs_add kernel/locking/lockdep.c:3209 [inline] validate_chain kernel/locking/lockdep.c:3825 [inline] __lock_acquire+0x2d07/0x7d10 kernel/locking/lockdep.c:5049 lock_acquire+0x1bb/0x4a0 kernel/locking/lockdep.c:5662 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x12d/0xaf0 kernel/locking/mutex.c:747 do_qc+0xca/0x730 fs/gfs2/quota.c:682 gfs2_quota_change+0x2f5/0x8e0 fs/gfs2/quota.c:1295 punch_hole+0x3155/0x3760 fs/gfs2/bmap.c:1955 gfs2_iomap_end+0x5e1/0x7a0 fs/gfs2/bmap.c:1174 iomap_iter+0x21a/0x1040 fs/iomap/iter.c:79 iomap_file_buffered_write+0x78b/0x8f0 fs/iomap/buffered-io.c:846 gfs2_file_buffered_write+0x4fe/0x880 fs/gfs2/file.c:1057 gfs2_file_write_iter+0x486/0xe90 fs/gfs2/file.c:1158 call_write_iter include/linux/fs.h:2265 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x4b1/0xa30 fs/read_write.c:584 ksys_write+0x14c/0x250 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 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.3.437/6145: #0: ffff88807d731268 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2ae/0x360 fs/file.c:1038 #1: ffff888074330460 (sb_writers#21){.+.+}-{0:0}, at: vfs_write+0x26b/0xa30 fs/read_write.c:580 #2: ffff888056294b38 (&sb->s_type->i_mutex_key#29){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline] #2: ffff888056294b38 (&sb->s_type->i_mutex_key#29){+.+.}-{3:3}, at: gfs2_file_write_iter+0x34b/0xe90 fs/gfs2/file.c:1115 #3: ffff888074330650 (sb_internal#3){.+.+}-{0:0}, at: gfs2_trans_begin+0x6b/0xe0 fs/gfs2/trans.c:118 #4: ffff888029d41058 (&sdp->sd_log_flush_lock){.+.+}-{3:3}, at: __gfs2_trans_begin+0x513/0x890 fs/gfs2/trans.c:87 #5: ffff888056294fd0 (&ip->i_rw_mutex){++++}-{3:3}, at: sweep_bh_for_rgrps fs/gfs2/bmap.c:1529 [inline] #5: ffff888056294fd0 (&ip->i_rw_mutex){++++}-{3:3}, at: punch_hole+0x24b8/0x3760 fs/gfs2/bmap.c:1854 stack backtrace: CPU: 0 PID: 6145 Comm: syz.3.437 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106 check_noncircular+0x296/0x330 kernel/locking/lockdep.c:2170 check_prev_add kernel/locking/lockdep.c:3090 [inline] check_prevs_add kernel/locking/lockdep.c:3209 [inline] validate_chain kernel/locking/lockdep.c:3825 [inline] __lock_acquire+0x2d07/0x7d10 kernel/locking/lockdep.c:5049 lock_acquire+0x1bb/0x4a0 kernel/locking/lockdep.c:5662 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x12d/0xaf0 kernel/locking/mutex.c:747 do_qc+0xca/0x730 fs/gfs2/quota.c:682 gfs2_quota_change+0x2f5/0x8e0 fs/gfs2/quota.c:1295 punch_hole+0x3155/0x3760 fs/gfs2/bmap.c:1955 gfs2_iomap_end+0x5e1/0x7a0 fs/gfs2/bmap.c:1174 iomap_iter+0x21a/0x1040 fs/iomap/iter.c:79 iomap_file_buffered_write+0x78b/0x8f0 fs/iomap/buffered-io.c:846 gfs2_file_buffered_write+0x4fe/0x880 fs/gfs2/file.c:1057 gfs2_file_write_iter+0x486/0xe90 fs/gfs2/file.c:1158 call_write_iter include/linux/fs.h:2265 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x4b1/0xa30 fs/read_write.c:584 ksys_write+0x14c/0x250 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fd56fd9c819 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fd570bef028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fd570015fa0 RCX: 00007fd56fd9c819 RDX: 000000000208e24b RSI: 00002000000004c0 RDI: 000000000000000a RBP: 00007fd56fe32c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fd570016038 R14: 00007fd570015fa0 R15: 00007ffd4ad4f278