gfs2: fsid=syz:syz.0: first mount done, others may mount ====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.1.252/5312 is trying to acquire lock: ffff0000f97a0ae0 (&sdp->sd_quota_mutex){+.+.}-{3:3}, at: do_qc+0xb8/0x648 fs/gfs2/quota.c:682 but task is already holding lock: ffff0000f5ae20c8 (&ip->i_rw_mutex){++++}-{3:3}, at: sweep_bh_for_rgrps fs/gfs2/bmap.c:1512 [inline] ffff0000f5ae20c8 (&ip->i_rw_mutex){++++}-{3:3}, at: punch_hole+0x2058/0x2d40 fs/gfs2/bmap.c:1837 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+0x64/0x304 kernel/locking/rwsem.c:1520 __gfs2_iomap_get+0x10c/0x100c fs/gfs2/bmap.c:856 gfs2_iomap_get+0xc0/0x120 fs/gfs2/bmap.c:1396 bh_get+0x1d8/0x5e4 fs/gfs2/quota.c:385 qdsb_get+0x1d4/0x37c fs/gfs2/quota.c:522 gfs2_quota_hold+0x16c/0x558 fs/gfs2/quota.c:608 punch_hole+0xae4/0x2d40 fs/gfs2/bmap.c:1798 __gfs2_punch_hole+0x66c/0x874 fs/gfs2/bmap.c:2452 gfs2_fallocate+0x378/0x478 fs/gfs2/file.c:1393 vfs_fallocate+0x4a4/0x5f4 fs/open.c:323 madvise_remove mm/madvise.c:1000 [inline] madvise_vma_behavior mm/madvise.c:1024 [inline] madvise_walk_vmas mm/madvise.c:1259 [inline] do_madvise+0x1374/0x2920 mm/madvise.c:1438 __do_sys_madvise mm/madvise.c:1451 [inline] __se_sys_madvise mm/madvise.c:1449 [inline] __arm64_sys_madvise+0xa4/0xc0 mm/madvise.c:1449 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x138 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 -> #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+0x293c/0x6544 kernel/locking/lockdep.c:5049 lock_acquire+0x20c/0x644 kernel/locking/lockdep.c:5662 __mutex_lock_common+0x190/0x1f38 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799 do_qc+0xb8/0x648 fs/gfs2/quota.c:682 gfs2_quota_change+0x238/0x718 fs/gfs2/quota.c:1295 punch_hole+0x2874/0x2d40 fs/gfs2/bmap.c:1938 __gfs2_punch_hole+0x66c/0x874 fs/gfs2/bmap.c:2452 gfs2_fallocate+0x378/0x478 fs/gfs2/file.c:1393 vfs_fallocate+0x4a4/0x5f4 fs/open.c:323 madvise_remove mm/madvise.c:1000 [inline] madvise_vma_behavior mm/madvise.c:1024 [inline] madvise_walk_vmas mm/madvise.c:1259 [inline] do_madvise+0x1374/0x2920 mm/madvise.c:1438 __do_sys_madvise mm/madvise.c:1451 [inline] __se_sys_madvise mm/madvise.c:1449 [inline] __arm64_sys_madvise+0xa4/0xc0 mm/madvise.c:1449 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x138 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 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.1.252/5312: #0: ffff0000f3b58460 (sb_writers#21){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3015 [inline] #0: ffff0000f3b58460 (sb_writers#21){.+.+}-{0:0}, at: vfs_fallocate+0x434/0x5f4 fs/open.c:322 #1: ffff0000f5ae1c30 (&sb->s_type->i_mutex_key#26){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline] #1: ffff0000f5ae1c30 (&sb->s_type->i_mutex_key#26){+.+.}-{3:3}, at: gfs2_fallocate+0x180/0x478 fs/gfs2/file.c:1374 #2: ffff0000f3b58650 (sb_internal#4){.+.+}-{0:0}, at: gfs2_trans_begin+0xa8/0x114 fs/gfs2/trans.c:118 #3: ffff0000f97a1058 (&sdp->sd_log_flush_lock){.+.+}-{3:3}, at: __gfs2_trans_begin+0x4f0/0x85c fs/gfs2/trans.c:87 #4: ffff0000f5ae20c8 (&ip->i_rw_mutex){++++}-{3:3}, at: sweep_bh_for_rgrps fs/gfs2/bmap.c:1512 [inline] #4: ffff0000f5ae20c8 (&ip->i_rw_mutex){++++}-{3:3}, at: punch_hole+0x2058/0x2d40 fs/gfs2/bmap.c:1837 stack backtrace: CPU: 0 PID: 5312 Comm: syz.1.252 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/30/2025 Call trace: dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165 __dump_stack+0x30/0x40 lib/dump_stack.c:88 dump_stack_lvl+0xf8/0x160 lib/dump_stack.c:106 dump_stack+0x1c/0x5c lib/dump_stack.c:113 print_circular_bug+0x148/0x1b0 kernel/locking/lockdep.c:2048 check_noncircular+0x240/0x2d4 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+0x293c/0x6544 kernel/locking/lockdep.c:5049 lock_acquire+0x20c/0x644 kernel/locking/lockdep.c:5662 __mutex_lock_common+0x190/0x1f38 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799 do_qc+0xb8/0x648 fs/gfs2/quota.c:682 gfs2_quota_change+0x238/0x718 fs/gfs2/quota.c:1295 punch_hole+0x2874/0x2d40 fs/gfs2/bmap.c:1938 __gfs2_punch_hole+0x66c/0x874 fs/gfs2/bmap.c:2452 gfs2_fallocate+0x378/0x478 fs/gfs2/file.c:1393 vfs_fallocate+0x4a4/0x5f4 fs/open.c:323 madvise_remove mm/madvise.c:1000 [inline] madvise_vma_behavior mm/madvise.c:1024 [inline] madvise_walk_vmas mm/madvise.c:1259 [inline] do_madvise+0x1374/0x2920 mm/madvise.c:1438 __do_sys_madvise mm/madvise.c:1451 [inline] __se_sys_madvise mm/madvise.c:1449 [inline] __arm64_sys_madvise+0xa4/0xc0 mm/madvise.c:1449 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x138 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585