======================================================== WARNING: possible irq lock inversion dependency detected 6.4.0-rc7-next-20230623 #1 Not tainted -------------------------------------------------------- syz-executor.1/33139 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 *** 4 locks held by syz-executor.1/33139: #0: ffff888006a33520 (&sig->exec_update_lock){++++}-{3:3}, at: __do_sys_perf_event_open+0x681/0x2a60 #1: ffff888042997ca8 (&ctx->mutex){+.+.}-{3:3}, at: __do_sys_perf_event_open+0xb79/0x2a60 #2: ffffffff8560b5a0 (rcu_callback){....}-{0:0}, at: rcu_core+0x83e/0x28b0 #3: 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 lock_acquire+0x1c7/0x4c0 __mutex_lock+0x12a/0x1a30 __flush_workqueue+0x137/0x1110 cgroup_procs_write_finish+0xeb/0x170 __cgroup_procs_write+0x371/0x6b0 cgroup_procs_write+0x26/0x60 cgroup_file_write+0x1e5/0x7c0 kernfs_fop_write_iter+0x3f7/0x610 vfs_write+0x97d/0xda0 ksys_write+0x122/0x250 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 __mod_memcg_lruvec_state+0x18d/0x2b0 mod_objcg_mlstate+0x119/0x230 drain_obj_stock+0x23e/0x580 refill_obj_stock+0x12d/0x5c0 kmem_cache_free+0x444/0x4d0 file_free_rcu+0xb5/0x100 rcu_core+0x8c8/0x28b0 __do_softirq+0x1b7/0x7d4 run_ksoftirqd+0x29/0x50 smpboot_thread_fn+0x40b/0x930 kthread+0x33f/0x440 ret_from_fork+0x2c/0x50 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 balance_dirty_pages+0x339/0x2640 balance_dirty_pages_ratelimited_flags+0xbce/0x1130 fault_dirty_shared_page+0x2b3/0x500 do_wp_page+0x3c8/0x3b00 __handle_mm_fault+0xcbc/0x2d20 handle_mm_fault+0x1af/0xba0 do_user_addr_fault+0x58e/0x12f0 exc_page_fault+0x9c/0x1a0 asm_exc_page_fault+0x26/0x30 -> (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 irq_exit_rcu+0x93/0xc0 sysvec_apic_timer_interrupt+0x6e/0x90 asm_sysvec_apic_timer_interrupt+0x1a/0x20 generic_exec_single+0x90/0x540 smp_call_function_single+0x327/0x410 task_function_call+0xe5/0x180 perf_install_in_context+0x2cb/0x570 __do_sys_perf_event_open+0x18bf/0x2a60 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 irq_exit_rcu+0x93/0xc0 sysvec_apic_timer_interrupt+0x6e/0x90 asm_sysvec_apic_timer_interrupt+0x1a/0x20 generic_exec_single+0x90/0x540 smp_call_function_single+0x327/0x410 task_function_call+0xe5/0x180 perf_install_in_context+0x2cb/0x570 __do_sys_perf_event_open+0x18bf/0x2a60 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 balance_dirty_pages+0x339/0x2640 balance_dirty_pages_ratelimited_flags+0xbce/0x1130 fault_dirty_shared_page+0x2b3/0x500 do_wp_page+0x3c8/0x3b00 __handle_mm_fault+0xcbc/0x2d20 handle_mm_fault+0x1af/0xba0 do_user_addr_fault+0x58e/0x12f0 exc_page_fault+0x9c/0x1a0 asm_exc_page_fault+0x26/0x30 } ... 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 irq_exit_rcu+0x93/0xc0 sysvec_apic_timer_interrupt+0x6e/0x90 asm_sysvec_apic_timer_interrupt+0x1a/0x20 generic_exec_single+0x90/0x540 smp_call_function_single+0x327/0x410 task_function_call+0xe5/0x180 perf_install_in_context+0x2cb/0x570 __do_sys_perf_event_open+0x18bf/0x2a60 do_syscall_64+0x3f/0x90 entry_SYSCALL_64_after_hwframe+0x6e/0xd8 stack backtrace: CPU: 0 PID: 33139 Comm: syz-executor.1 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 irq_exit_rcu+0x93/0xc0 sysvec_apic_timer_interrupt+0x6e/0x90 asm_sysvec_apic_timer_interrupt+0x1a/0x20 RIP: 0010:generic_exec_single+0x90/0x540 Code: f6 87 92 04 0f 92 c3 31 ff 89 de e8 5a d9 0a 00 84 db 0f 84 f4 03 00 00 e8 0d de 0a 00 4c 89 e6 89 ef 45 31 e4 e8 10 fb ff ff fb dd 0a 00 44 89 e0 5b 5d 41 5c 41 5d 41 5e e9 6b 8f 13 03 e8 RSP: 0018:ffff888049c4fb10 EFLAGS: 00000206 RAX: 0000000000000bdd RBX: 0000000000000200 RCX: ffffffff812d1fbf RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff81418307 RBP: 0000000000000001 R08: 0000000000000001 R09: fffffbfff0ef9b76 R10: ffffffff877cdbb7 R11: 0000000000000001 R12: 0000000000000000 R13: ffff888049c4fc38 R14: ffff888049c4fb88 R15: ffff888042de0014 smp_call_function_single+0x327/0x410 task_function_call+0xe5/0x180 perf_install_in_context+0x2cb/0x570 __do_sys_perf_event_open+0x18bf/0x2a60 do_syscall_64+0x3f/0x90 entry_SYSCALL_64_after_hwframe+0x6e/0xd8 RIP: 0033:0x7fe35e935b19 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fe35beab188 EFLAGS: 00000246 ORIG_RAX: 000000000000012a RAX: ffffffffffffffda RBX: 00007fe35ea48f60 RCX: 00007fe35e935b19 RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000000020000280 RBP: 00007fe35e98ff6d R08: 0000000000000000 R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffe1db35def R14: 00007fe35beab300 R15: 0000000000022000 ---------------- Code disassembly (best guess): 0: f6 87 92 04 0f 92 c3 testb $0xc3,-0x6df0fb6e(%rdi) 7: 31 ff xor %edi,%edi 9: 89 de mov %ebx,%esi b: e8 5a d9 0a 00 callq 0xad96a 10: 84 db test %bl,%bl 12: 0f 84 f4 03 00 00 je 0x40c 18: e8 0d de 0a 00 callq 0xade2a 1d: 4c 89 e6 mov %r12,%rsi 20: 89 ef mov %ebp,%edi 22: 45 31 e4 xor %r12d,%r12d 25: e8 10 fb ff ff callq 0xfffffb3a * 2a: e8 fb dd 0a 00 callq 0xade2a <-- trapping instruction 2f: 44 89 e0 mov %r12d,%eax 32: 5b pop %rbx 33: 5d pop %rbp 34: 41 5c pop %r12 36: 41 5d pop %r13 38: 41 5e pop %r14 3a: e9 6b 8f 13 03 jmpq 0x3138faa 3f: e8 .byte 0xe8