gfs2: fsid=syz:syz.0: first mount done, others may mount ====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.5.399/6595 is trying to acquire lock: ffff8880204e4ae0 (&sdp->sd_quota_mutex){+.+.}-{3:3}, at: do_qc+0xca/0x730 fs/gfs2/quota.c:678 but task is already holding lock: ffff88805ebe05e8 (&ip->i_rw_mutex){++++}-{3:3}, at: sweep_bh_for_rgrps fs/gfs2/bmap.c:1531 [inline] ffff88805ebe05e8 (&ip->i_rw_mutex){++++}-{3:3}, at: punch_hole+0x24ed/0x37a0 fs/gfs2/bmap.c:1856 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+0x44/0x2e0 kernel/locking/rwsem.c:1498 __gfs2_iomap_get+0x15b/0x1400 fs/gfs2/bmap.c:864 gfs2_iomap_get fs/gfs2/bmap.c:1415 [inline] gfs2_block_map+0x2a0/0x740 fs/gfs2/bmap.c:1230 bh_get+0x275/0x650 fs/gfs2/quota.c:385 qdsb_get+0x21c/0x3c0 fs/gfs2/quota.c:518 gfs2_quota_hold+0x194/0x5d0 fs/gfs2/quota.c:604 punch_hole+0xddb/0x37a0 fs/gfs2/bmap.c:1817 gfs2_iomap_end+0x5e1/0x7a0 fs/gfs2/bmap.c:1176 iomap_iter+0x22a/0xdb0 fs/iomap/iter.c:62 iomap_file_buffered_write+0x520/0x630 fs/iomap/buffered-io.c:814 gfs2_file_buffered_write+0x470/0x900 fs/gfs2/file.c:1058 gfs2_file_write_iter+0x497/0x1240 fs/gfs2/file.c:1166 call_write_iter include/linux/fs.h:2173 [inline] aio_write+0x54a/0x780 fs/aio.c:1594 __io_submit_one fs/aio.c:-1 [inline] io_submit_one+0x6cd/0x1380 fs/aio.c:2013 __do_sys_io_submit fs/aio.c:2072 [inline] __se_sys_io_submit+0x19d/0x310 fs/aio.c:2042 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 -> #0 (&sdp->sd_quota_mutex){+.+.}-{3:3}: check_prev_add kernel/locking/lockdep.c:3053 [inline] check_prevs_add kernel/locking/lockdep.c:3172 [inline] validate_chain kernel/locking/lockdep.c:3788 [inline] __lock_acquire+0x2c42/0x7d10 kernel/locking/lockdep.c:5012 lock_acquire+0x19e/0x400 kernel/locking/lockdep.c:5623 __mutex_lock_common+0x1e3/0x2400 kernel/locking/mutex.c:596 __mutex_lock kernel/locking/mutex.c:729 [inline] mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743 do_qc+0xca/0x730 fs/gfs2/quota.c:678 gfs2_quota_change+0x2f5/0x8e0 fs/gfs2/quota.c:1295 punch_hole+0x31d2/0x37a0 fs/gfs2/bmap.c:1957 gfs2_iomap_end+0x5e1/0x7a0 fs/gfs2/bmap.c:1176 iomap_iter+0x22a/0xdb0 fs/iomap/iter.c:62 iomap_file_buffered_write+0x520/0x630 fs/iomap/buffered-io.c:814 gfs2_file_buffered_write+0x470/0x900 fs/gfs2/file.c:1058 gfs2_file_write_iter+0x497/0x1240 fs/gfs2/file.c:1166 call_write_iter include/linux/fs.h:2173 [inline] aio_write+0x54a/0x780 fs/aio.c:1594 __io_submit_one fs/aio.c:-1 [inline] io_submit_one+0x6cd/0x1380 fs/aio.c:2013 __do_sys_io_submit fs/aio.c:2072 [inline] __se_sys_io_submit+0x19d/0x310 fs/aio.c:2042 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 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 *** 4 locks held by syz.5.399/6595: #0: ffff88805ebe0150 (&sb->s_type->i_mutex_key#34){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline] #0: ffff88805ebe0150 (&sb->s_type->i_mutex_key#34){+.+.}-{3:3}, at: gfs2_file_write_iter+0x35e/0x1240 fs/gfs2/file.c:1123 #1: ffff88805ef20650 (sb_internal#7){.+.+}-{0:0}, at: gfs2_trans_begin+0x6b/0xe0 fs/gfs2/trans.c:118 #2: ffff8880204e50a8 (&sdp->sd_log_flush_lock){.+.+}-{3:3}, at: __gfs2_trans_begin+0x515/0x890 fs/gfs2/trans.c:87 #3: ffff88805ebe05e8 (&ip->i_rw_mutex){++++}-{3:3}, at: sweep_bh_for_rgrps fs/gfs2/bmap.c:1531 [inline] #3: ffff88805ebe05e8 (&ip->i_rw_mutex){++++}-{3:3}, at: punch_hole+0x24ed/0x37a0 fs/gfs2/bmap.c:1856 stack backtrace: CPU: 1 PID: 6595 Comm: syz.5.399 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106 check_noncircular+0x296/0x330 kernel/locking/lockdep.c:2133 check_prev_add kernel/locking/lockdep.c:3053 [inline] check_prevs_add kernel/locking/lockdep.c:3172 [inline] validate_chain kernel/locking/lockdep.c:3788 [inline] __lock_acquire+0x2c42/0x7d10 kernel/locking/lockdep.c:5012 lock_acquire+0x19e/0x400 kernel/locking/lockdep.c:5623 __mutex_lock_common+0x1e3/0x2400 kernel/locking/mutex.c:596 __mutex_lock kernel/locking/mutex.c:729 [inline] mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743 do_qc+0xca/0x730 fs/gfs2/quota.c:678 gfs2_quota_change+0x2f5/0x8e0 fs/gfs2/quota.c:1295 punch_hole+0x31d2/0x37a0 fs/gfs2/bmap.c:1957 gfs2_iomap_end+0x5e1/0x7a0 fs/gfs2/bmap.c:1176 iomap_iter+0x22a/0xdb0 fs/iomap/iter.c:62 iomap_file_buffered_write+0x520/0x630 fs/iomap/buffered-io.c:814 gfs2_file_buffered_write+0x470/0x900 fs/gfs2/file.c:1058 gfs2_file_write_iter+0x497/0x1240 fs/gfs2/file.c:1166 call_write_iter include/linux/fs.h:2173 [inline] aio_write+0x54a/0x780 fs/aio.c:1594 __io_submit_one fs/aio.c:-1 [inline] io_submit_one+0x6cd/0x1380 fs/aio.c:2013 __do_sys_io_submit fs/aio.c:2072 [inline] __se_sys_io_submit+0x19d/0x310 fs/aio.c:2042 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f2a7d4ed799 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:00007f2a7b747028 EFLAGS: 00000246 ORIG_RAX: 00000000000000d1 RAX: ffffffffffffffda RBX: 00007f2a7d766fa0 RCX: 00007f2a7d4ed799 RDX: 0000200000000540 RSI: 000000000000003b RDI: 00007f2a7b71e000 RBP: 00007f2a7d583c99 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f2a7d767038 R14: 00007f2a7d766fa0 R15: 00007ffc6cd059d8