EXT4-fs (loop5): unmounting filesystem 00000000-0000-0000-0000-000000000000. EXT4-fs (loop6): unmounting filesystem 00000000-0000-0000-0000-000000000000. ======================================================== WARNING: possible irq lock inversion dependency detected 6.4.0-rc7-next-20230623 #1 Not tainted -------------------------------------------------------- syz-executor.0/5401 just changed the state of lock: ffffffff85815818 (blkg_stat_lock){+.-.}-{2:2}, at: __blkcg_rstat_flush.isra.0+0x11f/0x4e0 but this lock was taken by another, HARDIRQ-safe lock in the past: (per_cpu_ptr(&cgroup_rstat_cpu_lock, cpu)){-.-.}-{2:2} and interrupts could create inverse lock ordering between them. other info that might help us debug this: Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(blkg_stat_lock); local_irq_disable(); lock(per_cpu_ptr(&cgroup_rstat_cpu_lock, cpu)); lock(blkg_stat_lock); lock(per_cpu_ptr(&cgroup_rstat_cpu_lock, cpu)); *** DEADLOCK *** 3 locks held by syz-executor.0/5401: #0: ffff8880145c1130 (sk_lock-AF_NETLINK){+.+.}-{0:0}, at: netlink_insert+0xdd/0x1820 #1: ffffffff8560b5a0 (rcu_callback){....}-{0:0}, at: rcu_core+0x83e/0x28b0 #2: ffffffff8560b6c0 (rcu_read_lock){....}-{1:2}, at: __blkcg_rstat_flush.isra.0+0x93/0x4e0 the shortest dependencies between 2nd lock and 1st lock: -> (per_cpu_ptr(&cgroup_rstat_cpu_lock, cpu)){-.-.}-{2:2} { IN-HARDIRQ-W at: lock_acquire+0x19a/0x4c0 _raw_spin_lock_irqsave+0x3a/0x60 cgroup_rstat_updated+0xcb/0x2e0 __cgroup_account_cputime_field+0xa0/0x120 account_system_index_time+0x199/0x2c0 update_process_times+0x26/0x150 tick_sched_handle+0x8e/0x170 tick_sched_timer+0xe6/0x110 __hrtimer_run_queues+0x17f/0xb60 hrtimer_interrupt+0x2ef/0x750 __sysvec_apic_timer_interrupt+0xff/0x380 sysvec_apic_timer_interrupt+0x69/0x90 asm_sysvec_apic_timer_interrupt+0x1a/0x20 strcmp+0x6d/0xb0 __security_genfs_sid+0x240/0x620 security_genfs_sid+0xdc/0x3a0 inode_doinit_with_dentry+0xabf/0x1210 selinux_d_instantiate+0x27/0x30 security_d_instantiate+0x5a/0xf0 d_splice_alias+0x90/0xe30 kernfs_iop_lookup+0x283/0x330 lookup_open.isra.0+0x745/0x1400 path_openat+0x96c/0x2710 do_filp_open+0x1ba/0x410 do_sys_openat2+0x164/0x1d0 __x64_sys_openat+0x143/0x200 do_syscall_64+0x3f/0x90 entry_SYSCALL_64_after_hwframe+0x6e/0xd8 IN-SOFTIRQ-W at: lock_acquire+0x19a/0x4c0 _raw_spin_lock_irqsave+0x3a/0x60 cgroup_rstat_updated+0xcb/0x2e0 __cgroup_account_cputime+0x75/0xc0 update_curr+0x350/0x6d0 dequeue_task_fair+0x20e/0x14a0 load_balance+0xcb4/0x2790 rebalance_domains+0x66c/0xc00 __do_softirq+0x1b7/0x7d4 irq_exit_rcu+0x93/0xc0 sysvec_apic_timer_interrupt+0x6e/0x90 asm_sysvec_apic_timer_interrupt+0x1a/0x20 default_idle+0xf/0x20 default_idle_call+0x67/0xa0 do_idle+0x305/0x3c0 cpu_startup_entry+0x18/0x20 start_secondary+0x1ba/0x210 secondary_startup_64_no_verify+0x179/0x17b INITIAL USE at: lock_acquire+0x19a/0x4c0 _raw_spin_lock_irqsave+0x3a/0x60 cgroup_rstat_flush_locked+0x131/0xd80 cgroup_rstat_flush+0x37/0x50 do_flush_stats+0x97/0xf0 flush_memcg_stats_dwork+0x9/0x50 process_one_work+0xabf/0x1770 worker_thread+0x64f/0x12a0 kthread+0x33f/0x440 ret_from_fork+0x2c/0x50 } ... key at: [] __key.0+0x0/0x40 ... acquired at: _raw_spin_lock+0x2b/0x40 __blkcg_rstat_flush.isra.0+0x11f/0x4e0 blkcg_rstat_flush+0x87/0xb0 cgroup_rstat_flush_locked+0x706/0xd80 cgroup_rstat_flush+0x37/0x50 do_flush_stats+0x97/0xf0 mem_cgroup_wb_stats+0x3d8/0x4b0 wb_over_bg_thresh+0x30e/0x6a0 wb_workfn+0x486/0xed0 process_one_work+0xabf/0x1770 worker_thread+0x64f/0x12a0 kthread+0x33f/0x440 ret_from_fork+0x2c/0x50 -> (blkg_stat_lock){+.-.}-{2:2} { HARDIRQ-ON-W at: lock_acquire+0x19a/0x4c0 _raw_spin_lock+0x2b/0x40 __blkcg_rstat_flush.isra.0+0x11f/0x4e0 __blkg_release+0xfa/0x3b0 rcu_core+0x8c8/0x28b0 __do_softirq+0x1b7/0x7d4 do_softirq+0x48/0x80 __local_bh_enable_ip+0xed/0x110 netlink_insert+0xdd/0x1820 netlink_autobind.isra.0+0x345/0x600 netlink_sendmsg+0x9ef/0xe40 sock_sendmsg+0x1b6/0x200 __sys_sendto+0x254/0x360 __x64_sys_sendto+0xe1/0x1c0 do_syscall_64+0x3f/0x90 entry_SYSCALL_64_after_hwframe+0x6e/0xd8 IN-SOFTIRQ-W at: lock_acquire+0x19a/0x4c0 _raw_spin_lock+0x2b/0x40 __blkcg_rstat_flush.isra.0+0x11f/0x4e0 __blkg_release+0xfa/0x3b0 rcu_core+0x8c8/0x28b0 __do_softirq+0x1b7/0x7d4 do_softirq+0x48/0x80 __local_bh_enable_ip+0xed/0x110 netlink_insert+0xdd/0x1820 netlink_autobind.isra.0+0x345/0x600 netlink_sendmsg+0x9ef/0xe40 sock_sendmsg+0x1b6/0x200 __sys_sendto+0x254/0x360 __x64_sys_sendto+0xe1/0x1c0 do_syscall_64+0x3f/0x90 entry_SYSCALL_64_after_hwframe+0x6e/0xd8 INITIAL USE at: lock_acquire+0x19a/0x4c0 _raw_spin_lock+0x2b/0x40 __blkcg_rstat_flush.isra.0+0x11f/0x4e0 blkcg_rstat_flush+0x87/0xb0 cgroup_rstat_flush_locked+0x706/0xd80 cgroup_rstat_flush+0x37/0x50 do_flush_stats+0x97/0xf0 mem_cgroup_wb_stats+0x3d8/0x4b0 wb_over_bg_thresh+0x30e/0x6a0 wb_workfn+0x486/0xed0 process_one_work+0xabf/0x1770 worker_thread+0x64f/0x12a0 kthread+0x33f/0x440 ret_from_fork+0x2c/0x50 } ... key at: [] blkg_stat_lock+0x18/0x60 ... acquired at: __lock_acquire+0x8b8/0x6340 lock_acquire+0x19a/0x4c0 _raw_spin_lock+0x2b/0x40 __blkcg_rstat_flush.isra.0+0x11f/0x4e0 __blkg_release+0xfa/0x3b0 rcu_core+0x8c8/0x28b0 __do_softirq+0x1b7/0x7d4 do_softirq+0x48/0x80 __local_bh_enable_ip+0xed/0x110 netlink_insert+0xdd/0x1820 netlink_autobind.isra.0+0x345/0x600 netlink_sendmsg+0x9ef/0xe40 sock_sendmsg+0x1b6/0x200 __sys_sendto+0x254/0x360 __x64_sys_sendto+0xe1/0x1c0 do_syscall_64+0x3f/0x90 entry_SYSCALL_64_after_hwframe+0x6e/0xd8 stack backtrace: CPU: 1 PID: 5401 Comm: syz-executor.0 Not tainted 6.4.0-rc7-next-20230623 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 Call Trace: dump_stack_lvl+0x91/0xf0 print_irq_inversion_bug.part.0+0x3d5/0x570 mark_lock.part.0+0x900/0x2f50 __lock_acquire+0x8b8/0x6340 lock_acquire+0x19a/0x4c0 _raw_spin_lock+0x2b/0x40 __blkcg_rstat_flush.isra.0+0x11f/0x4e0 __blkg_release+0xfa/0x3b0 rcu_core+0x8c8/0x28b0 __do_softirq+0x1b7/0x7d4 do_softirq+0x48/0x80 __local_bh_enable_ip+0xed/0x110 netlink_insert+0xdd/0x1820 netlink_autobind.isra.0+0x345/0x600 netlink_sendmsg+0x9ef/0xe40 sock_sendmsg+0x1b6/0x200 __sys_sendto+0x254/0x360 __x64_sys_sendto+0xe1/0x1c0 do_syscall_64+0x3f/0x90 entry_SYSCALL_64_after_hwframe+0x6e/0xd8 RIP: 0033:0x7f96ebb3c8ac Code: fa fa ff ff 44 8b 4c 24 2c 4c 8b 44 24 20 89 c5 44 8b 54 24 28 48 8b 54 24 18 b8 2c 00 00 00 48 8b 74 24 10 8b 7c 24 08 0f 05 <48> 3d 00 f0 ff ff 77 34 89 ef 48 89 44 24 08 e8 20 fb ff ff 48 8b RSP: 002b:00007f96e90dd020 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f96e90dd110 RCX: 00007f96ebb3c8ac RDX: 0000000000000020 RSI: 00007f96e90dd160 RDI: 0000000000000005 RBP: 0000000000000000 R08: 00007f96e90dd074 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 00007f96e90dd0c8 R13: 00007f96e90dd160 R14: 0000000000000005 R15: 0000000000000000 loop6: detected capacity change from 0 to 512 EXT4-fs (loop6): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: none. EXT4-fs (loop6): unmounting filesystem 00000000-0000-0000-0000-000000000000.