R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 ====================================================== WARNING: possible circular locking dependency detected 6.8.0-rc2-syzkaller-00199-g021533194476 #0 Not tainted ------------------------------------------------------ syz-executor.0/19154 is trying to acquire lock: ffffffff8d7202a0 ( fs_reclaim ){+.+.}-{0:0} , at: might_alloc include/linux/sched/mm.h:303 [inline] , at: slab_pre_alloc_hook mm/slub.c:3761 [inline] , at: slab_alloc_node mm/slub.c:3842 [inline] , at: kmem_cache_alloc+0x4f/0x320 mm/slub.c:3867 but task is already holding lock: ffff888029843e88 (&ei->i_data_sem ){++++}-{3:3} , at: ext4_da_map_blocks fs/ext4/inode.c:1745 [inline] , at: ext4_da_get_block_prep+0x6cd/0x1340 fs/ext4/inode.c:1823 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 ( &ei->i_data_sem ){++++}-{3:3} : down_write+0x3a/0x50 kernel/locking/rwsem.c:1579 ext4_map_blocks+0x5ab/0x1770 fs/ext4/inode.c:614 mpage_map_one_extent fs/ext4/inode.c:2169 [inline] mpage_map_and_submit_extent fs/ext4/inode.c:2222 [inline] ext4_do_writepages+0x1852/0x3360 fs/ext4/inode.c:2685 ext4_writepages+0x30c/0x780 fs/ext4/inode.c:2774 do_writepages+0x1b4/0x690 mm/page-writeback.c:2553 __writeback_single_inode+0x158/0xe90 fs/fs-writeback.c:1625 writeback_sb_inodes+0x59d/0x1080 fs/fs-writeback.c:1916 __writeback_inodes_wb+0xff/0x2e0 fs/fs-writeback.c:1987 wb_writeback+0x7f8/0xaa0 fs/fs-writeback.c:2094 wb_check_background_flush fs/fs-writeback.c:2164 [inline] wb_do_writeback fs/fs-writeback.c:2252 [inline] wb_workfn+0x880/0xfe0 fs/fs-writeback.c:2279 process_one_work+0x835/0x1570 kernel/workqueue.c:2633 process_scheduled_works kernel/workqueue.c:2706 [inline] worker_thread+0x8b9/0x12a0 kernel/workqueue.c:2787 kthread+0x2c6/0x3b0 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:242 -> #2 ( jbd2_handle){++++}-{0:0}: start_this_handle+0x1103/0x15e0 fs/jbd2/transaction.c:463 jbd2__journal_start+0x395/0x850 fs/jbd2/transaction.c:520 __ext4_journal_start_sb+0x347/0x5e0 fs/ext4/ext4_jbd2.c:112 ext4_sample_last_mounted fs/ext4/file.c:837 [inline] ext4_file_open+0x636/0xc80 fs/ext4/file.c:866 do_dentry_open+0x8da/0x18c0 fs/open.c:953 do_open fs/namei.c:3641 [inline] path_openat+0x1e00/0x29a0 fs/namei.c:3798 do_filp_open+0x1de/0x440 fs/namei.c:3825 do_sys_openat2+0x17a/0x1e0 fs/open.c:1404 do_sys_open fs/open.c:1419 [inline] __do_sys_openat fs/open.c:1435 [inline] __se_sys_openat fs/open.c:1430 [inline] __x64_sys_openat+0x175/0x210 fs/open.c:1430 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd5/0x270 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6f/0x77 -> #1 (sb_internal){.+.+}-{0:0}: percpu_down_read include/linux/percpu-rwsem.h:51 [inline] __sb_start_write include/linux/fs.h:1639 [inline] sb_start_intwrite include/linux/fs.h:1822 [inline] ext4_evict_inode+0xe5f/0x1a40 fs/ext4/inode.c:212 evict+0x2ed/0x6c0 fs/inode.c:665 iput_final fs/inode.c:1739 [inline] iput.part.0+0x563/0x7b0 fs/inode.c:1765 iput+0x5c/0x80 fs/inode.c:1755 dentry_unlink_inode+0x295/0x440 fs/dcache.c:400 __dentry_kill+0x1d0/0x600 fs/dcache.c:603 shrink_kill fs/dcache.c:1048 [inline] shrink_dentry_list+0x140/0x5d0 fs/dcache.c:1075 prune_dcache_sb+0xeb/0x150 fs/dcache.c:1156 super_cache_scan+0x32a/0x550 fs/super.c:221 do_shrink_slab+0x426/0x1120 mm/shrinker.c:435 shrink_slab_memcg mm/shrinker.c:548 [inline] shrink_slab+0xa87/0x1310 mm/shrinker.c:626 shrink_one+0x493/0x7b0 mm/vmscan.c:4767 shrink_many mm/vmscan.c:4828 [inline] lru_gen_shrink_node mm/vmscan.c:4929 [inline] shrink_node+0x21d0/0x3790 mm/vmscan.c:5888 kswapd_shrink_node mm/vmscan.c:6693 [inline] balance_pgdat+0x9d2/0x1a90 mm/vmscan.c:6883 kswapd+0x5be/0xc00 mm/vmscan.c:7143 kthread+0x2c6/0x3b0 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:242 -> #0 (fs_reclaim){+.+.}-{0:0}: check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3869 [inline] __lock_acquire+0x244f/0x3b40 kernel/locking/lockdep.c:5137 lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1ae/0x520 kernel/locking/lockdep.c:5719 __fs_reclaim_acquire mm/page_alloc.c:3692 [inline] fs_reclaim_acquire+0x104/0x150 mm/page_alloc.c:3706 might_alloc include/linux/sched/mm.h:303 [inline] slab_pre_alloc_hook mm/slub.c:3761 [inline] slab_alloc_node mm/slub.c:3842 [inline] kmem_cache_alloc+0x4f/0x320 mm/slub.c:3867 kmem_cache_zalloc include/linux/slab.h:701 [inline] __es_alloc_extent fs/ext4/extents_status.c:483 [inline] ext4_es_insert_delayed_block+0x546/0x760 fs/ext4/extents_status.c:2090 ext4_insert_delayed_block fs/ext4/inode.c:1674 [inline] ext4_da_map_blocks fs/ext4/inode.c:1762 [inline] ext4_da_get_block_prep+0x854/0x1340 fs/ext4/inode.c:1823 ext4_block_write_begin+0x3da/0xef0 fs/ext4/inode.c:1053 ext4_da_write_begin+0x40e/0x8c0 fs/ext4/inode.c:2900 generic_perform_write+0x273/0x620 mm/filemap.c:3930 ext4_buffered_write_iter+0x11f/0x3d0 fs/ext4/file.c:299 ext4_file_write_iter+0x819/0x1960 fs/ext4/file.c:698 call_write_iter include/linux/fs.h:2085 [inline] new_sync_write fs/read_write.c:497 [inline] vfs_write+0x6de/0x1110 fs/read_write.c:590 ksys_write+0x12f/0x260 fs/read_write.c:643 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x7c/0x120 arch/x86/entry/common.c:321 do_fast_syscall_32+0x33/0x80 arch/x86/entry/common.c:346 entry_SYSENTER_compat_after_hwframe+0x7c/0x86 other info that might help us debug this: Chain exists of: fs_reclaim --> jbd2_handle --> &ei->i_data_sem Possible unsafe locking scenario: CPU0 CPU1 ---- ---- rlock(&ei->i_data_sem); lock(jbd2_handle); lock(&ei->i_data_sem); lock(fs_reclaim); *** DEADLOCK *** 4 locks held by syz-executor.0/19154: #0: ffff888021d0f2c8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xeb/0x180 fs/file.c:1191 #1: ffff88801dbc8420 (sb_writers#4){.+.+}-{0:0}, at: ksys_write+0x12f/0x260 fs/read_write.c:643 #2: ffff888029844000 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:802 [inline] #2: ffff888029844000 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x3d0 fs/ext4/file.c:294 #3: ffff888029843e88 (&ei->i_data_sem){++++}-{3:3}, at: ext4_da_map_blocks fs/ext4/inode.c:1745 [inline] #3: ffff888029843e88 (&ei->i_data_sem){++++}-{3:3}, at: ext4_da_get_block_prep+0x6cd/0x1340 fs/ext4/inode.c:1823 stack backtrace: CPU: 0 PID: 19154 Comm: syz-executor.0 Not tainted 6.8.0-rc2-syzkaller-00199-g021533194476 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106 check_noncircular+0x31b/0x400 kernel/locking/lockdep.c:2187 check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3869 [inline] __lock_acquire+0x244f/0x3b40 kernel/locking/lockdep.c:5137 lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1ae/0x520 kernel/locking/lockdep.c:5719 __fs_reclaim_acquire mm/page_alloc.c:3692 [inline] fs_reclaim_acquire+0x104/0x150 mm/page_alloc.c:3706 might_alloc include/linux/sched/mm.h:303 [inline] slab_pre_alloc_hook mm/slub.c:3761 [inline] slab_alloc_node mm/slub.c:3842 [inline] kmem_cache_alloc+0x4f/0x320 mm/slub.c:3867 kmem_cache_zalloc include/linux/slab.h:701 [inline] __es_alloc_extent fs/ext4/extents_status.c:483 [inline] ext4_es_insert_delayed_block+0x546/0x760 fs/ext4/extents_status.c:2090 ext4_insert_delayed_block fs/ext4/inode.c:1674 [inline] ext4_da_map_blocks fs/ext4/inode.c:1762 [inline] ext4_da_get_block_prep+0x854/0x1340 fs/ext4/inode.c:1823 ext4_block_write_begin+0x3da/0xef0 fs/ext4/inode.c:1053 ext4_da_write_begin+0x40e/0x8c0 fs/ext4/inode.c:2900 generic_perform_write+0x273/0x620 mm/filemap.c:3930 ext4_buffered_write_iter+0x11f/0x3d0 fs/ext4/file.c:299 ext4_file_write_iter+0x819/0x1960 fs/ext4/file.c:698 call_write_iter include/linux/fs.h:2085 [inline] new_sync_write fs/read_write.c:497 [inline] vfs_write+0x6de/0x1110 fs/read_write.c:590 ksys_write+0x12f/0x260 fs/read_write.c:643 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x7c/0x120 arch/x86/entry/common.c:321 do_fast_syscall_32+0x33/0x80 arch/x86/entry/common.c:346 entry_SYSENTER_compat_after_hwframe+0x7c/0x86 RIP: 0023:0xf7339579 Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 RSP: 002b:00000000f5f335ac EFLAGS: 00000292 ORIG_RAX: 0000000000000004 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000020000000 RDX: 000000000000003f RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 ---------------- Code disassembly (best guess), 2 bytes skipped: 0: 10 06 adc %al,(%rsi) 2: 03 74 b4 01 add 0x1(%rsp,%rsi,4),%esi 6: 10 07 adc %al,(%rdi) 8: 03 74 b0 01 add 0x1(%rax,%rsi,4),%esi c: 10 08 adc %cl,(%rax) e: 03 74 d8 01 add 0x1(%rax,%rbx,8),%esi 1e: 00 51 52 add %dl,0x52(%rcx) 21: 55 push %rbp 22: 89 e5 mov %esp,%ebp 24: 0f 34 sysenter 26: cd 80 int $0x80 * 28: 5d pop %rbp <-- trapping instruction 29: 5a pop %rdx 2a: 59 pop %rcx 2b: c3 ret 2c: 90 nop 2d: 90 nop 2e: 90 nop 2f: 90 nop 30: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi 37: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi