Hello, syzbot found the following issue on: HEAD commit: 47ac09b91bef Linux 6.11-rc4 git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=11770de5980000 kernel config: https://syzkaller.appspot.com/x/.config?x=df2f0ed7e30a639d dashboard link: https://syzkaller.appspot.com/bug?extid=1116a7b7b96b9c426a1a compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7bc7510fe41f/non_bootable_disk-47ac09b9.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/6db2a1c6b666/vmlinux-47ac09b9.xz kernel image: https://storage.googleapis.com/syzbot-assets/b1c782255526/bzImage-47ac09b9.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+1116a7b7b96b9c426a1a@xxxxxxxxxxxxxxxxxxxxxxxxx ====================================================== WARNING: possible circular locking dependency detected 6.11.0-rc4-syzkaller #0 Not tainted ------------------------------------------------------ kswapd0/80 is trying to acquire lock: ffff888038052610 (sb_internal#2){.+.+}-{0:0}, at: xfs_fs_dirty_inode+0x158/0x250 fs/xfs/xfs_super.c:691 but task is already holding lock: ffffffff8ea2fd20 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat mm/vmscan.c:6841 [inline] ffffffff8ea2fd20 (fs_reclaim){+.+.}-{0:0}, at: kswapd+0xbb4/0x35a0 mm/vmscan.c:7223 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (fs_reclaim){+.+.}-{0:0}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759 __fs_reclaim_acquire mm/page_alloc.c:3818 [inline] fs_reclaim_acquire+0x88/0x140 mm/page_alloc.c:3832 might_alloc include/linux/sched/mm.h:334 [inline] slab_pre_alloc_hook mm/slub.c:3939 [inline] slab_alloc_node mm/slub.c:4017 [inline] __do_kmalloc_node mm/slub.c:4157 [inline] __kmalloc_noprof+0xa9/0x400 mm/slub.c:4170 kmalloc_noprof include/linux/slab.h:685 [inline] xfs_attr_shortform_list+0x753/0x1900 fs/xfs/xfs_attr_list.c:117 xfs_attr_list+0x1d0/0x270 fs/xfs/xfs_attr_list.c:595 xfs_vn_listxattr+0x1d2/0x2c0 fs/xfs/xfs_xattr.c:341 vfs_listxattr fs/xattr.c:493 [inline] listxattr+0x107/0x290 fs/xattr.c:841 path_listxattr fs/xattr.c:865 [inline] __do_sys_listxattr fs/xattr.c:877 [inline] __se_sys_listxattr fs/xattr.c:874 [inline] __x64_sys_listxattr+0x173/0x230 fs/xattr.c:874 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #1 (&xfs_nondir_ilock_class#3){++++}-{3:3}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759 down_write_nested+0xa2/0x220 kernel/locking/rwsem.c:1695 xfs_fs_dirty_inode+0x18d/0x250 fs/xfs/xfs_super.c:693 __mark_inode_dirty+0x325/0xe20 fs/fs-writeback.c:2486 generic_update_time+0xb0/0xc0 fs/inode.c:2004 xfs_vn_update_time+0x2a5/0x600 fs/xfs/xfs_iops.c:1085 inode_update_time fs/inode.c:2016 [inline] __file_update_time fs/inode.c:2206 [inline] file_modified_flags+0x38a/0x4e0 fs/inode.c:2277 xfs_file_write_checks+0x7f2/0x9b0 fs/xfs/xfs_file.c:461 xfs_file_buffered_write+0x215/0xad0 fs/xfs/xfs_file.c:757 __kernel_write_iter+0x40d/0x900 fs/read_write.c:523 __kernel_write+0x120/0x180 fs/read_write.c:543 __dump_emit+0x237/0x360 fs/coredump.c:816 elf_core_dump+0x31d0/0x4720 fs/binfmt_elf.c:2068 do_coredump+0x1b04/0x2a30 fs/coredump.c:767 get_signal+0x13fa/0x1740 kernel/signal.c:2902 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] irqentry_exit_to_user_mode+0x79/0x280 kernel/entry/common.c:231 exc_page_fault+0x590/0x8c0 arch/x86/mm/fault.c:1542 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 -> #0 (sb_internal#2){.+.+}-{0:0}: check_prev_add kernel/locking/lockdep.c:3133 [inline] check_prevs_add kernel/locking/lockdep.c:3252 [inline] validate_chain+0x18e0/0x5900 kernel/locking/lockdep.c:3868 __lock_acquire+0x137a/0x2040 kernel/locking/lockdep.c:5142 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759 percpu_down_read include/linux/percpu-rwsem.h:51 [inline] __sb_start_write include/linux/fs.h:1675 [inline] sb_start_intwrite include/linux/fs.h:1858 [inline] xfs_trans_alloc+0xe5/0x830 fs/xfs/xfs_trans.c:264 xfs_fs_dirty_inode+0x158/0x250 fs/xfs/xfs_super.c:691 __mark_inode_dirty+0x325/0xe20 fs/fs-writeback.c:2486 mark_inode_dirty_sync include/linux/fs.h:2436 [inline] iput+0x1fe/0x930 fs/inode.c:1861 __dentry_kill+0x20d/0x630 fs/dcache.c:610 shrink_kill+0xa9/0x2c0 fs/dcache.c:1055 shrink_dentry_list+0x2c0/0x5b0 fs/dcache.c:1082 prune_dcache_sb+0x10f/0x180 fs/dcache.c:1163 super_cache_scan+0x34f/0x4b0 fs/super.c:221 do_shrink_slab+0x701/0x1160 mm/shrinker.c:435 shrink_slab+0x1093/0x14d0 mm/shrinker.c:662 shrink_one+0x43b/0x850 mm/vmscan.c:4815 shrink_many mm/vmscan.c:4876 [inline] lru_gen_shrink_node mm/vmscan.c:4954 [inline] shrink_node+0x3799/0x3de0 mm/vmscan.c:5934 kswapd_shrink_node mm/vmscan.c:6762 [inline] balance_pgdat mm/vmscan.c:6954 [inline] kswapd+0x1bcd/0x35a0 mm/vmscan.c:7223 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 other info that might help us debug this: Chain exists of: sb_internal#2 --> &xfs_nondir_ilock_class#3 --> fs_reclaim Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(fs_reclaim); lock(&xfs_nondir_ilock_class#3); lock(fs_reclaim); rlock(sb_internal#2); *** DEADLOCK *** 2 locks held by kswapd0/80: #0: ffffffff8ea2fd20 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat mm/vmscan.c:6841 [inline] #0: ffffffff8ea2fd20 (fs_reclaim){+.+.}-{0:0}, at: kswapd+0xbb4/0x35a0 mm/vmscan.c:7223 #1: ffff8880380520e0 (&type->s_umount_key#48){.+.+}-{3:3}, at: super_trylock_shared fs/super.c:562 [inline] #1: ffff8880380520e0 (&type->s_umount_key#48){.+.+}-{3:3}, at: super_cache_scan+0x94/0x4b0 fs/super.c:196 stack backtrace: CPU: 0 UID: 0 PID: 80 Comm: kswapd0 Not tainted 6.11.0-rc4-syzkaller #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Call Trace: <TASK> __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2186 check_prev_add kernel/locking/lockdep.c:3133 [inline] check_prevs_add kernel/locking/lockdep.c:3252 [inline] validate_chain+0x18e0/0x5900 kernel/locking/lockdep.c:3868 __lock_acquire+0x137a/0x2040 kernel/locking/lockdep.c:5142 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759 percpu_down_read include/linux/percpu-rwsem.h:51 [inline] __sb_start_write include/linux/fs.h:1675 [inline] sb_start_intwrite include/linux/fs.h:1858 [inline] xfs_trans_alloc+0xe5/0x830 fs/xfs/xfs_trans.c:264 xfs_fs_dirty_inode+0x158/0x250 fs/xfs/xfs_super.c:691 __mark_inode_dirty+0x325/0xe20 fs/fs-writeback.c:2486 mark_inode_dirty_sync include/linux/fs.h:2436 [inline] iput+0x1fe/0x930 fs/inode.c:1861 __dentry_kill+0x20d/0x630 fs/dcache.c:610 shrink_kill+0xa9/0x2c0 fs/dcache.c:1055 shrink_dentry_list+0x2c0/0x5b0 fs/dcache.c:1082 prune_dcache_sb+0x10f/0x180 fs/dcache.c:1163 super_cache_scan+0x34f/0x4b0 fs/super.c:221 do_shrink_slab+0x701/0x1160 mm/shrinker.c:435 shrink_slab+0x1093/0x14d0 mm/shrinker.c:662 shrink_one+0x43b/0x850 mm/vmscan.c:4815 shrink_many mm/vmscan.c:4876 [inline] lru_gen_shrink_node mm/vmscan.c:4954 [inline] shrink_node+0x3799/0x3de0 mm/vmscan.c:5934 kswapd_shrink_node mm/vmscan.c:6762 [inline] balance_pgdat mm/vmscan.c:6954 [inline] kswapd+0x1bcd/0x35a0 mm/vmscan.c:7223 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 </TASK> --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup
