===================================== WARNING: bad unlock balance detected! 5.6.0-rc7-syzkaller #0 Not tainted ------------------------------------- syz-executor.2/13764 is trying to release lock (rcu_callback) at: [] rcu_lock_release+0x0/0x20 include/linux/rcupdate.h:209 but there are no more locks to release! other info that might help us debug this: 1 lock held by syz-executor.2/13764: #0: ffff88808d89a0d8 (&type->s_umount_key#54/1){+.+.}, at: alloc_super+0x160/0x760 fs/super.c:229 stack backtrace: CPU: 0 PID: 13764 Comm: syz-executor.2 Not tainted 5.6.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1e9/0x30e lib/dump_stack.c:118 print_unlock_imbalance_bug+0x20b/0x240 kernel/locking/lockdep.c:4007 __lock_release kernel/locking/lockdep.c:4241 [inline] lock_release+0x37c/0x720 kernel/locking/lockdep.c:4502 rcu_do_batch kernel/rcu/tree.c:2188 [inline] rcu_core+0x7f0/0x1080 kernel/rcu/tree.c:2410 __do_softirq+0x268/0x7c5 kernel/softirq.c:292 invoke_softirq kernel/softirq.c:373 [inline] irq_exit+0x223/0x230 kernel/softirq.c:413 exiting_irq arch/x86/include/asm/apic.h:546 [inline] smp_apic_timer_interrupt+0x113/0x280 arch/x86/kernel/apic/apic.c:1146 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829 RIP: 0010:preempt_count_add+0x42/0x150 kernel/sched/core.c:3786 Code: 03 49 bf 00 00 00 00 00 fc ff df 42 8a 04 38 84 c0 0f 85 b5 00 00 00 83 3d 6a 30 dd 09 00 75 11 65 8b 05 0d 9d b0 7e 0f b6 c0 <3d> f5 00 00 00 73 5a 65 8b 05 fc 9c b0 7e 25 ff ff ff 7f 39 d8 75 RSP: 0018:ffffc900174b7538 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000001 RBX: 0000000000000001 RCX: ffffffff8a632000 RDX: ffffc900174b7e48 RSI: ffffffff81c32485 RDI: 0000000000000001 RBP: 1ffff92002e96ec4 R08: 000000000000000b R09: ffffc900174b76c8 R10: fffff52002e96ecf R11: 0000000000000000 R12: ffffc900174b7658 R13: ffffc900174b7620 R14: ffffffff81c32485 R15: dffffc0000000000 unwind_next_frame+0xbc/0x1cf0 arch/x86/kernel/unwind_orc.c:395 arch_stack_walk+0xb4/0xe0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xad/0x150 kernel/stacktrace.c:123 save_stack mm/kasan/common.c:72 [inline] set_track mm/kasan/common.c:80 [inline] __kasan_kmalloc+0x118/0x1c0 mm/kasan/common.c:515 slab_post_alloc_hook mm/slab.h:584 [inline] slab_alloc mm/slab.c:3320 [inline] kmem_cache_alloc+0x1f5/0x2d0 mm/slab.c:3484 mempool_alloc_slab+0x49/0x70 mm/mempool.c:513 mempool_alloc+0xf1/0x5a0 mm/mempool.c:393 bio_alloc_bioset+0x1af/0x5d0 block/bio.c:480 bio_alloc include/linux/bio.h:400 [inline] submit_bh_wbc+0x1c7/0x6d0 fs/buffer.c:3086 submit_bh fs/buffer.c:3118 [inline] __bread_slow fs/buffer.c:1217 [inline] __bread_gfp+0x1a7/0x350 fs/buffer.c:1399 sb_bread include/linux/buffer_head.h:307 [inline] read_ntfs_boot_sector fs/ntfs/super.c:687 [inline] ntfs_fill_super+0x7f6/0x89f0 fs/ntfs/super.c:2784 mount_bdev+0x232/0x340 fs/super.c:1417 legacy_get_tree+0xea/0x180 fs/fs_context.c:622 vfs_get_tree+0x88/0x270 fs/super.c:1547 do_new_mount fs/namespace.c:2822 [inline] do_mount+0x17d5/0x2440 fs/namespace.c:3107 __do_sys_mount fs/namespace.c:3316 [inline] __se_sys_mount+0xd3/0x100 fs/namespace.c:3293 do_syscall_64+0xf3/0x1b0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45f29a Code: b8 a6 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 4d 8c fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 2a 8c fb ff c3 66 0f 1f 84 00 00 00 00 00 RSP: 002b:00007f5dc4eb4a68 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f5dc4eb56d4 RCX: 000000000045f29a RDX: 00007f5dc4eb4ae0 RSI: 0000000020000080 RDI: 00007f5dc4eb4b00 RBP: 000000000076bf00 R08: 00007f5dc4eb4b40 R09: 00007f5dc4eb4ae0 R10: 0000000000000000 R11: 0000000000000206 R12: 00000000ffffffff R13: 0000000000000be7 R14: 00000000004ce08e R15: 000000000076bf0c