gfs2: fsid=syz:syz.0: first mount done, others may mount gfs2: fsid=syz:syz.0: found 1 quota changes ====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.4.370/5482 is trying to acquire lock: ffff888019ddcae0 (&sdp->sd_quota_mutex){+.+.}-{3:3}, at: do_qc+0xca/0x730 fs/gfs2/quota.c:678 but task is already holding lock: ffff88805f3ed080 (&ip->i_rw_mutex){++++}-{3:3}, at: sweep_bh_for_rgrps fs/gfs2/bmap.c:1514 [inline] ffff88805f3ed080 (&ip->i_rw_mutex){++++}-{3:3}, at: punch_hole+0x23a1/0x3520 fs/gfs2/bmap.c:1839 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+0x155/0x13e0 fs/gfs2/bmap.c:858 gfs2_iomap_get fs/gfs2/bmap.c:1398 [inline] gfs2_block_map+0x229/0x670 fs/gfs2/bmap.c:1213 bh_get+0x227/0x5f0 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+0xd81/0x3520 fs/gfs2/bmap.c:1800 do_shrink+0x7a1/0x910 fs/gfs2/bmap.c:2020 gfs2_setattr_size+0x150/0x810 fs/gfs2/bmap.c:2144 gfs2_setattr+0x252/0x400 fs/gfs2/inode.c:2006 notify_change+0xbcd/0xee0 fs/attr.c:505 do_truncate+0x197/0x220 fs/open.c:65 handle_truncate fs/namei.c:3273 [inline] do_open fs/namei.c:3620 [inline] path_openat+0x28af/0x2f30 fs/namei.c:3750 do_filp_open+0x1b3/0x3e0 fs/namei.c:3777 do_sys_openat2+0x142/0x4a0 fs/open.c:1255 do_sys_open fs/open.c:1271 [inline] __do_sys_open fs/open.c:1279 [inline] __se_sys_open fs/open.c:1275 [inline] __x64_sys_open+0x11b/0x140 fs/open.c:1275 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+0x2c33/0x7c60 kernel/locking/lockdep.c:5012 lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623 __mutex_lock_common+0x1eb/0x2390 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+0x2f8b/0x3520 fs/gfs2/bmap.c:1940 do_shrink+0x7a1/0x910 fs/gfs2/bmap.c:2020 gfs2_setattr_size+0x150/0x810 fs/gfs2/bmap.c:2144 gfs2_setattr+0x252/0x400 fs/gfs2/inode.c:2006 notify_change+0xbcd/0xee0 fs/attr.c:505 do_truncate+0x197/0x220 fs/open.c:65 handle_truncate fs/namei.c:3273 [inline] do_open fs/namei.c:3620 [inline] path_openat+0x28af/0x2f30 fs/namei.c:3750 do_filp_open+0x1b3/0x3e0 fs/namei.c:3777 do_sys_openat2+0x142/0x4a0 fs/open.c:1255 do_sys_open fs/open.c:1271 [inline] __do_sys_open fs/open.c:1279 [inline] __se_sys_open fs/open.c:1275 [inline] __x64_sys_open+0x11b/0x140 fs/open.c:1275 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 *** 5 locks held by syz.4.370/5482: #0: ffff88807955c460 (sb_writers#22){.+.+}-{0:0}, at: mnt_want_write+0x3d/0x90 fs/namespace.c:386 #1: ffff88805f3ecbe8 (&sb->s_type->i_mutex_key#25){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline] #1: ffff88805f3ecbe8 (&sb->s_type->i_mutex_key#25){+.+.}-{3:3}, at: do_truncate+0x183/0x220 fs/open.c:63 #2: ffff88807955c650 (sb_internal#3){.+.+}-{0:0}, at: gfs2_trans_begin+0x6b/0xe0 fs/gfs2/trans.c:118 #3: ffff888019ddd0a8 (&sdp->sd_log_flush_lock){.+.+}-{3:3}, at: __gfs2_trans_begin+0x50f/0x880 fs/gfs2/trans.c:87 #4: ffff88805f3ed080 (&ip->i_rw_mutex){++++}-{3:3}, at: sweep_bh_for_rgrps fs/gfs2/bmap.c:1514 [inline] #4: ffff88805f3ed080 (&ip->i_rw_mutex){++++}-{3:3}, at: punch_hole+0x23a1/0x3520 fs/gfs2/bmap.c:1839 stack backtrace: CPU: 0 PID: 5482 Comm: syz.4.370 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106 check_noncircular+0x274/0x310 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+0x2c33/0x7c60 kernel/locking/lockdep.c:5012 lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623 __mutex_lock_common+0x1eb/0x2390 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+0x2f8b/0x3520 fs/gfs2/bmap.c:1940 do_shrink+0x7a1/0x910 fs/gfs2/bmap.c:2020 gfs2_setattr_size+0x150/0x810 fs/gfs2/bmap.c:2144 gfs2_setattr+0x252/0x400 fs/gfs2/inode.c:2006 notify_change+0xbcd/0xee0 fs/attr.c:505 do_truncate+0x197/0x220 fs/open.c:65 handle_truncate fs/namei.c:3273 [inline] do_open fs/namei.c:3620 [inline] path_openat+0x28af/0x2f30 fs/namei.c:3750 do_filp_open+0x1b3/0x3e0 fs/namei.c:3777 do_sys_openat2+0x142/0x4a0 fs/open.c:1255 do_sys_open fs/open.c:1271 [inline] __do_sys_open fs/open.c:1279 [inline] __se_sys_open fs/open.c:1275 [inline] __x64_sys_open+0x11b/0x140 fs/open.c:1275 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: 0033:0x7f49882bf749 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:00007f4986526038 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 00007f4988515fa0 RCX: 00007f49882bf749 RDX: 1df2a23c5997fa1f RSI: 0000000000084242 RDI: 0000200000000100 RBP: 00007f4988343f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f4988516038 R14: 00007f4988515fa0 R15: 00007ffc8b5d0f08