loop0: detected capacity change from 0 to 32768 XFS (loop0): Mounting V5 Filesystem c496e05e-540d-4c72-b591-04d79d8b4eeb XFS (loop0): Ending clean mount XFS (loop0): Quotacheck needed: Please wait. XFS (loop0): Quotacheck: Done. ============================================ WARNING: possible recursive locking detected syzkaller #0 Not tainted -------------------------------------------- syz.0.0/5329 is trying to acquire lock: ffff888047baa698 (&xfs_nondir_ilock_class){++++}-{4:4}, at: xfs_reclaim_inode fs/xfs/xfs_icache.c:1044 [inline] ffff888047baa698 (&xfs_nondir_ilock_class){++++}-{4:4}, at: xfs_icwalk_process_inode fs/xfs/xfs_icache.c:1736 [inline] ffff888047baa698 (&xfs_nondir_ilock_class){++++}-{4:4}, at: xfs_icwalk_ag+0x125f/0x1970 fs/xfs/xfs_icache.c:1818 but task is already holding lock: ffff888047ba9798 (&xfs_nondir_ilock_class){++++}-{4:4}, at: xfs_ilock_for_iomap fs/xfs/xfs_iomap.c:789 [inline] ffff888047ba9798 (&xfs_nondir_ilock_class){++++}-{4:4}, at: xfs_buffered_write_iomap_begin+0x53a/0x1ca0 fs/xfs/xfs_iomap.c:1793 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&xfs_nondir_ilock_class); lock(&xfs_nondir_ilock_class); *** DEADLOCK *** May be due to missing lock nesting notation 5 locks held by syz.0.0/5329: #0: ffff8880122cd2b8 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x246/0x320 fs/file.c:1261 #1: ffff8880426ec420 (sb_writers#12){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2710 [inline] #1: ffff8880426ec420 (sb_writers#12){.+.+}-{0:0}, at: vfs_write+0x227/0xb90 fs/read_write.c:684 #2: ffff888047ba99b0 (&sb->s_type->i_mutex_key#25){++++}-{4:4}, at: xfs_ilock+0xee/0x3b0 fs/xfs/xfs_inode.c:149 #3: ffff888047ba9798 (&xfs_nondir_ilock_class){++++}-{4:4}, at: xfs_ilock_for_iomap fs/xfs/xfs_iomap.c:789 [inline] #3: ffff888047ba9798 (&xfs_nondir_ilock_class){++++}-{4:4}, at: xfs_buffered_write_iomap_begin+0x53a/0x1ca0 fs/xfs/xfs_iomap.c:1793 #4: ffff8880426ec0e0 (&type->s_umount_key#52){.+.+}-{4:4}, at: super_trylock_shared fs/super.c:565 [inline] #4: ffff8880426ec0e0 (&type->s_umount_key#52){.+.+}-{4:4}, at: super_cache_scan+0x91/0x4b0 fs/super.c:198 stack backtrace: CPU: 0 UID: 0 PID: 5329 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_deadlock_bug+0x279/0x290 kernel/locking/lockdep.c:3041 check_deadlock kernel/locking/lockdep.c:3093 [inline] validate_chain kernel/locking/lockdep.c:3895 [inline] __lock_acquire+0x253f/0x2cf0 kernel/locking/lockdep.c:5237 lock_acquire+0xf0/0x2e0 kernel/locking/lockdep.c:5868 down_write_nested+0x9d/0x210 kernel/locking/rwsem.c:1706 xfs_reclaim_inode fs/xfs/xfs_icache.c:1044 [inline] xfs_icwalk_process_inode fs/xfs/xfs_icache.c:1736 [inline] xfs_icwalk_ag+0x125f/0x1970 fs/xfs/xfs_icache.c:1818 xfs_icwalk fs/xfs/xfs_icache.c:1866 [inline] xfs_reclaim_inodes_nr+0x1e5/0x260 fs/xfs/xfs_icache.c:1110 super_cache_scan+0x41b/0x4b0 fs/super.c:229 do_shrink_slab+0x6df/0x1170 mm/shrinker.c:437 shrink_slab+0xdf2/0x1150 mm/shrinker.c:664 shrink_one+0x2d9/0x710 mm/vmscan.c:4928 shrink_many mm/vmscan.c:4989 [inline] lru_gen_shrink_node mm/vmscan.c:5067 [inline] shrink_node+0x3197/0x3a90 mm/vmscan.c:6047 shrink_zones mm/vmscan.c:6300 [inline] do_try_to_free_pages+0x6a2/0x1980 mm/vmscan.c:6362 try_to_free_pages+0x8f2/0xe90 mm/vmscan.c:6601 __perform_reclaim mm/page_alloc.c:4424 [inline] __alloc_pages_direct_reclaim+0x148/0x310 mm/page_alloc.c:4446 __alloc_pages_slowpath+0x57d/0xd40 mm/page_alloc.c:4846 __alloc_frozen_pages_noprof+0x322/0x380 mm/page_alloc.c:5263 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2490 alloc_frozen_pages_noprof mm/mempolicy.c:2561 [inline] alloc_pages_noprof+0xa8/0x1a0 mm/mempolicy.c:2581 stack_depot_save_flags+0x73c/0x810 lib/stackdepot.c:685 kasan_save_stack mm/kasan/common.c:58 [inline] kasan_save_track+0x4f/0x80 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_krealloc+0xeb/0x110 mm/kasan/common.c:485 kasan_krealloc include/linux/kasan.h:283 [inline] __do_krealloc mm/slub.c:6626 [inline] krealloc_node_align_noprof+0x238/0x390 mm/slub.c:6689 xfs_iext_realloc_root fs/xfs/libxfs/xfs_iext_tree.c:613 [inline] xfs_iext_insert_raw+0x13c/0x3270 fs/xfs/libxfs/xfs_iext_tree.c:647 xfs_iext_insert+0x36/0x260 fs/xfs/libxfs/xfs_iext_tree.c:684 xfs_bmap_add_extent_hole_delay+0x4e8/0x850 fs/xfs/xfs_iomap.c:1429 xfs_bmapi_reserve_delalloc+0xc98/0xde0 fs/xfs/xfs_iomap.c:1548 xfs_buffered_write_iomap_begin+0x1362/0x1ca0 fs/xfs/xfs_iomap.c:1986 iomap_iter+0x600/0x1020 fs/iomap/iter.c:110 iomap_file_buffered_write+0x92f/0xb30 fs/iomap/buffered-io.c:1224 xfs_file_buffered_write+0x212/0x8c0 fs/xfs/xfs_file.c:1013 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x61d/0xb90 fs/read_write.c:688 ksys_write+0x150/0x270 fs/read_write.c:740 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fcdba99c819 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:00007fcdbb918fe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fcdbac15fa0 RCX: 00007fcdba99c819 RDX: 00000000fffffdab RSI: 0000200000000000 RDI: 0000000000000005 RBP: 00007fcdbaa32c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fcdbac16038 R14: 00007fcdbac15fa0 R15: 00007fff292a0ad8