EXT4-fs (loop8): mounted filesystem without journal. Opts: ,errors=continue. Quota mode: writeback. ====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.8.2372/17046 is trying to acquire lock: ffff888070fcb768 (&dquot->dq_lock){+.+.}-{3:3}, at: dquot_commit+0x5a/0x410 fs/quota/dquot.c:507 but task is already holding lock: ffff88805e6bc840 (&ei->i_data_sem/2){++++}-{3:3}, at: ext4_map_blocks+0x8b2/0x1b30 fs/ext4/inode.c:666 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&ei->i_data_sem/2){++++}-{3:3}: down_write+0x38/0x60 kernel/locking/rwsem.c:1551 ext4_map_blocks+0x8b2/0x1b30 fs/ext4/inode.c:666 ext4_getblk+0x16d/0x630 fs/ext4/inode.c:870 ext4_bread+0x26/0x180 fs/ext4/inode.c:923 ext4_quota_write+0x230/0x570 fs/ext4/super.c:6596 write_blk fs/quota/quota_tree.c:64 [inline] find_free_dqentry fs/quota/quota_tree.c:307 [inline] do_insert_tree+0x115c/0x1970 fs/quota/quota_tree.c:364 do_insert_tree+0x5b1/0x1970 fs/quota/quota_tree.c:366 do_insert_tree+0x5b1/0x1970 fs/quota/quota_tree.c:366 do_insert_tree+0x5b1/0x1970 fs/quota/quota_tree.c:366 dq_insert_tree fs/quota/quota_tree.c:392 [inline] qtree_write_dquot+0x361/0x4b0 fs/quota/quota_tree.c:411 v2_write_dquot+0x108/0x190 fs/quota/quota_v2.c:358 dquot_acquire+0x2d5/0x520 fs/quota/dquot.c:472 ext4_acquire_dquot+0x2d9/0x4a0 fs/ext4/super.c:6205 dqget+0x778/0xeb0 fs/quota/dquot.c:988 __dquot_initialize+0x328/0xcb0 fs/quota/dquot.c:1517 ext4_rmdir+0x104/0x9f0 fs/ext4/namei.c:3201 vfs_rmdir+0x1b2/0x430 fs/namei.c:4149 do_rmdir+0x295/0x710 fs/namei.c:4210 __do_sys_rmdir fs/namei.c:4229 [inline] __se_sys_rmdir fs/namei.c:4227 [inline] __x64_sys_rmdir+0x45/0x50 fs/namei.c:4227 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 -> #1 (&s->s_dquot.dqio_sem){++++}-{3:3}: down_read+0x44/0x2e0 kernel/locking/rwsem.c:1498 v2_read_dquot+0x4a/0x110 fs/quota/quota_v2.c:332 dquot_acquire+0x152/0x520 fs/quota/dquot.c:463 ext4_acquire_dquot+0x2d9/0x4a0 fs/ext4/super.c:6205 dqget+0x778/0xeb0 fs/quota/dquot.c:988 __dquot_initialize+0x328/0xcb0 fs/quota/dquot.c:1517 ext4_rmdir+0x104/0x9f0 fs/ext4/namei.c:3201 vfs_rmdir+0x1b2/0x430 fs/namei.c:4149 do_rmdir+0x295/0x710 fs/namei.c:4210 __do_sys_rmdir fs/namei.c:4229 [inline] __se_sys_rmdir fs/namei.c:4227 [inline] __x64_sys_rmdir+0x45/0x50 fs/namei.c:4227 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 (&dquot->dq_lock){+.+.}-{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 dquot_commit+0x5a/0x410 fs/quota/dquot.c:507 ext4_write_dquot+0x1f0/0x360 fs/ext4/super.c:6185 mark_dquot_dirty fs/quota/dquot.c:372 [inline] mark_all_dquot_dirty+0xf9/0x400 fs/quota/dquot.c:412 __dquot_alloc_space+0x5d0/0xe20 fs/quota/dquot.c:1752 dquot_alloc_space_nodirty include/linux/quotaops.h:297 [inline] dquot_alloc_space include/linux/quotaops.h:310 [inline] dquot_alloc_block include/linux/quotaops.h:334 [inline] ext4_mb_new_blocks+0xf68/0x4940 fs/ext4/mballoc.c:5734 ext4_ext_map_blocks+0x146f/0x64e0 fs/ext4/extents.c:4341 ext4_map_blocks+0x981/0x1b30 fs/ext4/inode.c:673 ext4_iomap_alloc fs/ext4/inode.c:3408 [inline] ext4_iomap_begin+0x807/0xb80 fs/ext4/inode.c:3458 iomap_iter+0x620/0xdb0 fs/iomap/iter.c:74 __iomap_dio_rw+0x1014/0x1a70 fs/iomap/direct-io.c:585 iomap_dio_rw+0x38/0x90 fs/iomap/direct-io.c:672 ext4_dio_write_iter fs/ext4/file.c:540 [inline] ext4_file_write_iter+0x132b/0x17b0 fs/ext4/file.c:660 do_iter_readv_writev+0x497/0x600 fs/read_write.c:-1 do_iter_write+0x205/0x7b0 fs/read_write.c:855 vfs_writev fs/read_write.c:928 [inline] do_pwritev+0x204/0x340 fs/read_write.c:1025 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: Chain exists of: &dquot->dq_lock --> &s->s_dquot.dqio_sem --> &ei->i_data_sem/2 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&ei->i_data_sem/2); lock(&s->s_dquot.dqio_sem); lock(&ei->i_data_sem/2); lock(&dquot->dq_lock); *** DEADLOCK *** 4 locks held by syz.8.2372/17046: #0: ffff888064974460 (sb_writers#5){.+.+}-{0:0}, at: vfs_writev fs/read_write.c:927 [inline] #0: ffff888064974460 (sb_writers#5){.+.+}-{0:0}, at: do_pwritev+0x1f2/0x340 fs/read_write.c:1025 #1: ffff88805e6bc9b8 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline] #1: ffff88805e6bc9b8 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: ext4_dio_write_iter fs/ext4/file.c:478 [inline] #1: ffff88805e6bc9b8 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: ext4_file_write_iter+0x6b2/0x17b0 fs/ext4/file.c:660 #2: ffff88805e6bc840 (&ei->i_data_sem/2){++++}-{3:3}, at: ext4_map_blocks+0x8b2/0x1b30 fs/ext4/inode.c:666 #3: ffffffff8c23ef98 (dquot_srcu){....}-{0:0}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:311 stack backtrace: CPU: 1 PID: 17046 Comm: syz.8.2372 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 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 dquot_commit+0x5a/0x410 fs/quota/dquot.c:507 ext4_write_dquot+0x1f0/0x360 fs/ext4/super.c:6185 mark_dquot_dirty fs/quota/dquot.c:372 [inline] mark_all_dquot_dirty+0xf9/0x400 fs/quota/dquot.c:412 __dquot_alloc_space+0x5d0/0xe20 fs/quota/dquot.c:1752 dquot_alloc_space_nodirty include/linux/quotaops.h:297 [inline] dquot_alloc_space include/linux/quotaops.h:310 [inline] dquot_alloc_block include/linux/quotaops.h:334 [inline] ext4_mb_new_blocks+0xf68/0x4940 fs/ext4/mballoc.c:5734 ext4_ext_map_blocks+0x146f/0x64e0 fs/ext4/extents.c:4341 ext4_map_blocks+0x981/0x1b30 fs/ext4/inode.c:673 ext4_iomap_alloc fs/ext4/inode.c:3408 [inline] ext4_iomap_begin+0x807/0xb80 fs/ext4/inode.c:3458 iomap_iter+0x620/0xdb0 fs/iomap/iter.c:74 __iomap_dio_rw+0x1014/0x1a70 fs/iomap/direct-io.c:585 iomap_dio_rw+0x38/0x90 fs/iomap/direct-io.c:672 ext4_dio_write_iter fs/ext4/file.c:540 [inline] ext4_file_write_iter+0x132b/0x17b0 fs/ext4/file.c:660 do_iter_readv_writev+0x497/0x600 fs/read_write.c:-1 do_iter_write+0x205/0x7b0 fs/read_write.c:855 vfs_writev fs/read_write.c:928 [inline] do_pwritev+0x204/0x340 fs/read_write.c:1025 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: 0033:0x7f335788aec9 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:00007f3355af2038 EFLAGS: 00000246 ORIG_RAX: 0000000000000148 RAX: ffffffffffffffda RBX: 00007f3357ae1fa0 RCX: 00007f335788aec9 RDX: 0000000000000001 RSI: 0000200000000240 RDI: 0000000000000004 RBP: 00007f335790df91 R08: 0000000000000000 R09: 0000000000000003 R10: 0000000000007800 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f3357ae2038 R14: 00007f3357ae1fa0 R15: 00007ffdc21da808