Hello, syzbot found the following issue on: HEAD commit: e8b0ccb2a787 Merge tag '9p-for-6.9-rc3' of https://github... git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=12f9ee15180000 kernel config: https://syzkaller.appspot.com/x/.config?x=8c2c72b264636e25 dashboard link: https://syzkaller.appspot.com/bug?extid=88a60d3f927e2460d4ac compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 userspace arch: i386 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-e8b0ccb2.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/36cfb6ee2b7e/vmlinux-e8b0ccb2.xz kernel image: https://storage.googleapis.com/syzbot-assets/86b45977fab6/bzImage-e8b0ccb2.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+88a60d3f927e2460d4ac@xxxxxxxxxxxxxxxxxxxxxxxxx ====================================================== WARNING: possible circular locking dependency detected 6.9.0-rc2-syzkaller-00207-ge8b0ccb2a787 #0 Not tainted ------------------------------------------------------ kswapd1/112 is trying to acquire lock: ffff888064068640 (&f->sem){+.+.}-{3:3}, at: jffs2_do_clear_inode+0x5a/0x470 fs/jffs2/readinode.c:1419 but task is already holding lock: ffffffff8d939440 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat+0x166/0x1a10 mm/vmscan.c:6782 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (fs_reclaim){+.+.}-{0:0}: __fs_reclaim_acquire mm/page_alloc.c:3698 [inline] fs_reclaim_acquire+0x102/0x160 mm/page_alloc.c:3712 might_alloc include/linux/sched/mm.h:312 [inline] slab_pre_alloc_hook mm/slub.c:3746 [inline] slab_alloc_node mm/slub.c:3827 [inline] kmem_cache_alloc+0x4f/0x320 mm/slub.c:3852 jffs2_do_read_inode+0x3e8/0x670 fs/jffs2/readinode.c:1372 jffs2_iget+0x2c3/0xed0 fs/jffs2/fs.c:277 jffs2_do_fill_super+0x44b/0xa60 fs/jffs2/fs.c:577 jffs2_fill_super+0x283/0x370 fs/jffs2/super.c:289 mtd_get_sb+0x2ce/0x490 drivers/mtd/mtdsuper.c:57 mtd_get_sb_by_nr drivers/mtd/mtdsuper.c:88 [inline] get_tree_mtd+0x6ce/0x860 drivers/mtd/mtdsuper.c:141 vfs_get_tree+0x8f/0x380 fs/super.c:1779 do_new_mount fs/namespace.c:3352 [inline] path_mount+0x6e1/0x1f10 fs/namespace.c:3679 do_mount fs/namespace.c:3692 [inline] __do_sys_mount fs/namespace.c:3898 [inline] __se_sys_mount fs/namespace.c:3875 [inline] __ia32_sys_mount+0x295/0x320 fs/namespace.c:3875 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x7a/0x120 arch/x86/entry/common.c:321 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:346 entry_SYSENTER_compat_after_hwframe+0x7f/0x89 -> #0 (&f->sem){+.+.}-{3:3}: 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+0x2478/0x3b30 kernel/locking/lockdep.c:5137 lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719 __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752 jffs2_do_clear_inode+0x5a/0x470 fs/jffs2/readinode.c:1419 evict+0x2ed/0x6c0 fs/inode.c:667 dispose_list+0x117/0x1e0 fs/inode.c:700 prune_icache_sb+0xeb/0x150 fs/inode.c:885 super_cache_scan+0x375/0x550 fs/super.c:223 do_shrink_slab+0x44f/0x11c0 mm/shrinker.c:435 shrink_slab_memcg mm/shrinker.c:548 [inline] shrink_slab+0xa87/0x1310 mm/shrinker.c:626 shrink_one+0x493/0x7c0 mm/vmscan.c:4774 shrink_many mm/vmscan.c:4835 [inline] lru_gen_shrink_node+0x89f/0x1750 mm/vmscan.c:4935 shrink_node mm/vmscan.c:5894 [inline] kswapd_shrink_node mm/vmscan.c:6704 [inline] balance_pgdat+0x10d1/0x1a10 mm/vmscan.c:6895 kswapd+0x5ea/0xbf0 mm/vmscan.c:7164 kthread+0x2c1/0x3a0 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(fs_reclaim); lock(&f->sem); lock(fs_reclaim); lock(&f->sem); *** DEADLOCK *** 2 locks held by kswapd1/112: #0: ffffffff8d939440 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat+0x166/0x1a10 mm/vmscan.c:6782 #1: ffff88805e1aa0e0 (&type->s_umount_key#88){++++}-{3:3}, at: super_trylock_shared fs/super.c:561 [inline] #1: ffff88805e1aa0e0 (&type->s_umount_key#88){++++}-{3:3}, at: super_cache_scan+0x96/0x550 fs/super.c:196 stack backtrace: CPU: 1 PID: 112 Comm: kswapd1 Not tainted 6.9.0-rc2-syzkaller-00207-ge8b0ccb2a787 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114 check_noncircular+0x31a/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+0x2478/0x3b30 kernel/locking/lockdep.c:5137 lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719 __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752 jffs2_do_clear_inode+0x5a/0x470 fs/jffs2/readinode.c:1419 evict+0x2ed/0x6c0 fs/inode.c:667 dispose_list+0x117/0x1e0 fs/inode.c:700 prune_icache_sb+0xeb/0x150 fs/inode.c:885 super_cache_scan+0x375/0x550 fs/super.c:223 do_shrink_slab+0x44f/0x11c0 mm/shrinker.c:435 shrink_slab_memcg mm/shrinker.c:548 [inline] shrink_slab+0xa87/0x1310 mm/shrinker.c:626 shrink_one+0x493/0x7c0 mm/vmscan.c:4774 shrink_many mm/vmscan.c:4835 [inline] lru_gen_shrink_node+0x89f/0x1750 mm/vmscan.c:4935 shrink_node mm/vmscan.c:5894 [inline] kswapd_shrink_node mm/vmscan.c:6704 [inline] balance_pgdat+0x10d1/0x1a10 mm/vmscan.c:6895 kswapd+0x5ea/0xbf0 mm/vmscan.c:7164 kthread+0x2c1/0x3a0 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243 </TASK> --- This report is generated by a bot. 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