BTRFS info (device loop7): enabling free space tree BTRFS info (device loop7): enabling auto defrag BTRFS info (device loop7): use lzo compression, level 1 ====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.7.1927/22649 is trying to acquire lock: ffff88802aa52800 (sb_internal#5){.+.+}-{0:0}, at: btrfs_dirty_inode+0x9f/0x190 fs/btrfs/inode.c:6446 but task is already holding lock: ffff88802aa52688 (sb_pagefaults#5){.+.+}-{0:0}, at: do_page_mkwrite+0x14a/0x310 mm/memory.c:3754 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #6 (sb_pagefaults#5){.+.+}-{0:0}: percpu_down_read_internal include/linux/percpu-rwsem.h:53 [inline] percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline] __sb_start_write include/linux/fs/super.h:19 [inline] sb_start_pagefault include/linux/fs/super.h:159 [inline] btrfs_page_mkwrite+0x32b/0x1a50 fs/btrfs/file.c:1837 do_page_mkwrite+0x14a/0x310 mm/memory.c:3754 wp_page_shared mm/memory.c:4155 [inline] do_wp_page+0x20a7/0x3d20 mm/memory.c:4378 handle_pte_fault mm/memory.c:6520 [inline] __handle_mm_fault mm/memory.c:6645 [inline] handle_mm_fault+0xcac/0x2690 mm/memory.c:6814 do_user_addr_fault+0x746/0x1340 arch/x86/mm/fault.c:1394 handle_page_fault arch/x86/mm/fault.c:1483 [inline] exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1536 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595 rep_movs_alternative+0x33/0xa0 arch/x86/lib/copy_user_64.S:60 copy_user_generic arch/x86/include/asm/uaccess_64.h:126 [inline] raw_copy_to_user arch/x86/include/asm/uaccess_64.h:147 [inline] copy_to_user_iter lib/iov_iter.c:25 [inline] iterate_ubuf include/linux/iov_iter.h:30 [inline] iterate_and_advance2 include/linux/iov_iter.h:302 [inline] iterate_and_advance include/linux/iov_iter.h:330 [inline] _copy_to_iter+0x255/0x1810 lib/iov_iter.c:197 copy_page_to_iter+0x23f/0x330 lib/iov_iter.c:374 copy_folio_to_iter include/linux/uio.h:204 [inline] filemap_read+0x7b7/0x11e0 mm/filemap.c:2875 new_sync_read fs/read_write.c:493 [inline] vfs_read+0x59e/0xa90 fs/read_write.c:574 ksys_read+0x156/0x270 fs/read_write.c:716 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #5 (&mm->mmap_lock){++++}-{4:4}: down_read_killable+0xa4/0x220 kernel/locking/rwsem.c:1599 mmap_read_lock_killable+0x1d/0x70 include/linux/mmap_lock.h:609 get_mmap_lock_carefully mm/mmap_lock.c:450 [inline] lock_mm_and_find_vma+0x2d6/0x340 mm/mmap_lock.c:501 do_user_addr_fault+0x343/0x1340 arch/x86/mm/fault.c:1366 handle_page_fault arch/x86/mm/fault.c:1483 [inline] exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1536 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595 stac arch/x86/include/asm/smap.h:-1 [inline] filldir64+0x29e/0x620 fs/readdir.c:365 dir_emit include/linux/fs.h:3608 [inline] kernfs_fop_readdir+0x583/0x960 fs/kernfs/dir.c:1999 iterate_dir+0x2f1/0x4e0 fs/readdir.c:110 __do_sys_getdents64 fs/readdir.c:399 [inline] __se_sys_getdents64+0xf1/0x280 fs/readdir.c:384 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #4 (&root->kernfs_rwsem){++++}-{4:4}: down_write+0x3a/0x50 kernel/locking/rwsem.c:1631 kernfs_add_one+0x41/0x6f0 fs/kernfs/dir.c:825 kernfs_create_dir_ns+0x1a1/0x230 fs/kernfs/dir.c:1130 sysfs_create_dir_ns+0x12f/0x2a0 fs/sysfs/dir.c:59 create_dir lib/kobject.c:73 [inline] kobject_add_internal+0x62c/0xce0 lib/kobject.c:240 kobject_add_varg lib/kobject.c:374 [inline] kobject_init_and_add+0x12b/0x1a0 lib/kobject.c:457 btrfs_sysfs_add_qgroups+0x118/0x2f0 fs/btrfs/sysfs.c:2604 btrfs_quota_enable+0x274/0x1e20 fs/btrfs/qgroup.c:1032 btrfs_ioctl_quota_ctl+0x189/0x1f0 fs/btrfs/ioctl.c:3566 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xff/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #3 (&fs_info->qgroup_ioctl_lock){+.+.}-{4:4}: __mutex_lock_common kernel/locking/rtmutex_api.c:559 [inline] mutex_lock_nested+0x5a/0x1d0 kernel/locking/rtmutex_api.c:578 btrfs_quota_enable+0x2b1/0x1e20 fs/btrfs/qgroup.c:1061 btrfs_ioctl_quota_ctl+0x189/0x1f0 fs/btrfs/ioctl.c:3566 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xff/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #2 (btrfs_trans_num_extwriters){++++}-{0:0}: join_transaction+0x18a/0xc60 fs/btrfs/transaction.c:324 start_transaction+0x6ed/0x17d0 fs/btrfs/transaction.c:718 btrfs_create_common+0x15c/0x310 fs/btrfs/inode.c:6984 vfs_mknod+0x443/0x610 fs/namei.c:5269 filename_mknodat+0x3cf/0x670 fs/namei.c:-1 __do_sys_mknod fs/namei.c:5356 [inline] __se_sys_mknod+0x3a/0x150 fs/namei.c:5353 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #1 (btrfs_trans_num_writers){++++}-{0:0}: join_transaction+0x169/0xc60 fs/btrfs/transaction.c:323 start_transaction+0x6ed/0x17d0 fs/btrfs/transaction.c:718 btrfs_create_common+0x15c/0x310 fs/btrfs/inode.c:6984 vfs_mknod+0x443/0x610 fs/namei.c:5269 filename_mknodat+0x3cf/0x670 fs/namei.c:-1 __do_sys_mknod fs/namei.c:5356 [inline] __se_sys_mknod+0x3a/0x150 fs/namei.c:5353 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (sb_internal#5){.+.+}-{0:0}: check_prev_add kernel/locking/lockdep.c:3181 [inline] check_prevs_add kernel/locking/lockdep.c:3300 [inline] validate_chain kernel/locking/lockdep.c:3924 [inline] __lock_acquire+0x1520/0x2ce0 kernel/locking/lockdep.c:5253 lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5886 percpu_down_read_internal include/linux/percpu-rwsem.h:53 [inline] percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline] __sb_start_write include/linux/fs/super.h:19 [inline] sb_start_intwrite include/linux/fs/super.h:177 [inline] start_transaction+0x575/0x17d0 fs/btrfs/transaction.c:712 btrfs_dirty_inode+0x9f/0x190 fs/btrfs/inode.c:6446 file_update_time_flags+0x28b/0x450 fs/inode.c:2481 btrfs_page_mkwrite+0x60b/0x1a50 fs/btrfs/file.c:1878 do_page_mkwrite+0x14a/0x310 mm/memory.c:3754 wp_page_shared mm/memory.c:4155 [inline] do_wp_page+0x20a7/0x3d20 mm/memory.c:4378 handle_pte_fault mm/memory.c:6520 [inline] __handle_mm_fault mm/memory.c:6645 [inline] handle_mm_fault+0xcac/0x2690 mm/memory.c:6814 do_user_addr_fault+0x746/0x1340 arch/x86/mm/fault.c:1394 handle_page_fault arch/x86/mm/fault.c:1483 [inline] exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1536 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595 rep_movs_alternative+0x33/0xa0 arch/x86/lib/copy_user_64.S:60 copy_user_generic arch/x86/include/asm/uaccess_64.h:126 [inline] raw_copy_to_user arch/x86/include/asm/uaccess_64.h:147 [inline] copy_to_user_iter lib/iov_iter.c:25 [inline] iterate_ubuf include/linux/iov_iter.h:30 [inline] iterate_and_advance2 include/linux/iov_iter.h:302 [inline] iterate_and_advance include/linux/iov_iter.h:330 [inline] _copy_to_iter+0x255/0x1810 lib/iov_iter.c:197 copy_page_to_iter+0x23f/0x330 lib/iov_iter.c:374 copy_folio_to_iter include/linux/uio.h:204 [inline] filemap_read+0x7b7/0x11e0 mm/filemap.c:2875 new_sync_read fs/read_write.c:493 [inline] vfs_read+0x59e/0xa90 fs/read_write.c:574 ksys_read+0x156/0x270 fs/read_write.c:716 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f other info that might help us debug this: Chain exists of: sb_internal#5 --> &mm->mmap_lock --> sb_pagefaults#5 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- rlock(sb_pagefaults#5); lock(&mm->mmap_lock); lock(sb_pagefaults#5); rlock(sb_internal#5); *** DEADLOCK *** locks held by syz.7.1927/22649: 3, last CPU#0: #0: ffff88806015e128 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x252/0x320 fs/file.c:1259 #1: ffff88805abd11b0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_trylock include/linux/mmap_lock.h:619 [inline] #1: ffff88805abd11b0 (&mm->mmap_lock){++++}-{4:4}, at: get_mmap_lock_carefully mm/mmap_lock.c:441 [inline] #1: ffff88805abd11b0 (&mm->mmap_lock){++++}-{4:4}, at: lock_mm_and_find_vma+0x36/0x340 mm/mmap_lock.c:501 #2: ffff88802aa52688 (sb_pagefaults#5){.+.+}-{0:0}, at: do_page_mkwrite+0x14a/0x310 mm/memory.c:3754 stack backtrace: CPU: 0 UID: 0 PID: 22649 Comm: syz.7.1927 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_circular_bug+0x2e1/0x300 kernel/locking/lockdep.c:2059 check_noncircular+0x12e/0x150 kernel/locking/lockdep.c:2191 check_prev_add kernel/locking/lockdep.c:3181 [inline] check_prevs_add kernel/locking/lockdep.c:3300 [inline] validate_chain kernel/locking/lockdep.c:3924 [inline] __lock_acquire+0x1520/0x2ce0 kernel/locking/lockdep.c:5253 lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5886 percpu_down_read_internal include/linux/percpu-rwsem.h:53 [inline] percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline] __sb_start_write include/linux/fs/super.h:19 [inline] sb_start_intwrite include/linux/fs/super.h:177 [inline] start_transaction+0x575/0x17d0 fs/btrfs/transaction.c:712 btrfs_dirty_inode+0x9f/0x190 fs/btrfs/inode.c:6446 file_update_time_flags+0x28b/0x450 fs/inode.c:2481 btrfs_page_mkwrite+0x60b/0x1a50 fs/btrfs/file.c:1878 do_page_mkwrite+0x14a/0x310 mm/memory.c:3754 wp_page_shared mm/memory.c:4155 [inline] do_wp_page+0x20a7/0x3d20 mm/memory.c:4378 handle_pte_fault mm/memory.c:6520 [inline] __handle_mm_fault mm/memory.c:6645 [inline] handle_mm_fault+0xcac/0x2690 mm/memory.c:6814 do_user_addr_fault+0x746/0x1340 arch/x86/mm/fault.c:1394 handle_page_fault arch/x86/mm/fault.c:1483 [inline] exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1536 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595 RIP: 0010:rep_movs_alternative+0x33/0xa0 arch/x86/lib/copy_user_64.S:61 Code: 73 25 85 c9 74 0f 8a 06 88 07 48 ff c7 48 ff c6 48 ff c9 75 f1 e9 fd 2f 05 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 8b 06 <48> 89 07 48 83 c6 08 48 83 c7 08 83 e9 08 74 db 83 f9 08 73 e8 eb RSP: 0018:ffffc90005a7f838 EFLAGS: 00050202 RAX: 656c6c616b7a7973 RBX: ffff88804c2df000 RCX: 000000000000000a RDX: 0000000000000000 RSI: ffff88804c2df000 RDI: 0000200000000ec0 RBP: ffffc90005a7f9a8 R08: ffff88804c2df009 R09: 1ffff1100985be01 R10: dffffc0000000000 R11: ffffed100985be02 R12: 1ffff92000b4ffaf R13: 0000200000000ec0 R14: ffffc90005a7fd88 R15: 000000000000000a copy_user_generic arch/x86/include/asm/uaccess_64.h:126 [inline] raw_copy_to_user arch/x86/include/asm/uaccess_64.h:147 [inline] copy_to_user_iter lib/iov_iter.c:25 [inline] iterate_ubuf include/linux/iov_iter.h:30 [inline] iterate_and_advance2 include/linux/iov_iter.h:302 [inline] iterate_and_advance include/linux/iov_iter.h:330 [inline] _copy_to_iter+0x255/0x1810 lib/iov_iter.c:197 copy_page_to_iter+0x23f/0x330 lib/iov_iter.c:374 copy_folio_to_iter include/linux/uio.h:204 [inline] filemap_read+0x7b7/0x11e0 mm/filemap.c:2875 new_sync_read fs/read_write.c:493 [inline] vfs_read+0x59e/0xa90 fs/read_write.c:574 ksys_read+0x156/0x270 fs/read_write.c:716 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa180d0e0d9 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:00007fa17ef66028 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007fa180f95fa0 RCX: 00007fa180d0e0d9 RDX: 0000000000002020 RSI: 0000200000000ec0 RDI: 0000000000000004 RBP: 00007fa180da5024 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fa180f96038 R14: 00007fa180f95fa0 R15: 00007ffc84b81818 ---------------- Code disassembly (best guess): 0: 73 25 jae 0x27 2: 85 c9 test %ecx,%ecx 4: 74 0f je 0x15 6: 8a 06 mov (%rsi),%al 8: 88 07 mov %al,(%rdi) a: 48 ff c7 inc %rdi d: 48 ff c6 inc %rsi 10: 48 ff c9 dec %rcx 13: 75 f1 jne 0x6 15: e9 fd 2f 05 00 jmp 0x53017 1a: 66 2e 0f 1f 84 00 00 cs nopw 0x0(%rax,%rax,1) 21: 00 00 00 24: 0f 1f 00 nopl (%rax) 27: 48 8b 06 mov (%rsi),%rax * 2a: 48 89 07 mov %rax,(%rdi) <-- trapping instruction 2d: 48 83 c6 08 add $0x8,%rsi 31: 48 83 c7 08 add $0x8,%rdi 35: 83 e9 08 sub $0x8,%ecx 38: 74 db je 0x15 3a: 83 f9 08 cmp $0x8,%ecx 3d: 73 e8 jae 0x27 3f: eb .byte 0xeb