syz-executor.6: attempt to access beyond end of device loop6: rw=0, sector=0, nr_sectors = 1 limit=0 FAT-fs (loop6): unable to read boot sector ======================================================== WARNING: possible irq lock inversion dependency detected 6.4.0-rc7-next-20230622 #1 Not tainted -------------------------------------------------------- rcu_preempt/14 just changed the state of lock: ffffffff85814c18 (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 *** 2 locks held by rcu_preempt/14: #0: ffffffff8560b5a0 (rcu_callback){....}-{0:0}, at: rcu_core+0x83e/0x2860 #1: 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 __stack_depot_save+0x126/0x460 kasan_save_stack+0x32/0x50 kasan_set_track+0x25/0x30 __kasan_slab_alloc+0x59/0x70 kmem_cache_alloc+0x16b/0x370 __create_object+0x3c/0xc90 kmem_cache_alloc+0x20b/0x370 security_inode_alloc+0x38/0x160 inode_init_always+0xbb2/0xea0 alloc_inode+0x84/0x240 iget_locked+0x199/0x660 kernfs_get_inode+0x4b/0x520 kernfs_iop_lookup+0x1e9/0x330 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 enqueue_task_fair+0x6a9/0x1ca0 activate_task+0xe7/0x250 ttwu_do_activate+0x10d/0x7a0 sched_ttwu_pending+0x1da/0x3b0 __flush_smp_call_function_queue+0x594/0xea0 __sysvec_call_function_single+0x96/0x2a0 sysvec_call_function_single+0x33/0x90 asm_sysvec_call_function_single+0x1a/0x20 __sanitizer_cov_trace_pc+0x0/0x70 is_module_text_address+0x14/0x1d0 kernel_text_address+0x35/0xc0 __kernel_text_address+0xd/0x40 unwind_get_return_address+0x59/0xa0 arch_stack_walk+0x9d/0xf0 stack_trace_save+0x90/0xd0 kasan_save_stack+0x22/0x50 kasan_set_track+0x25/0x30 kasan_save_free_info+0x2b/0x50 __kasan_slab_free+0x10a/0x190 kmem_cache_free+0x10d/0x4d0 rcu_core+0x8c8/0x2860 __do_softirq+0x1b7/0x7d4 irq_exit_rcu+0x93/0xc0 sysvec_apic_timer_interrupt+0x6e/0x90 asm_sysvec_apic_timer_interrupt+0x1a/0x20 __sanitizer_cov_trace_pc+0xb/0x70 __is_insn_slot_addr+0x12a/0x290 kernel_text_address+0x48/0xc0 __kernel_text_address+0xd/0x40 unwind_get_return_address+0x59/0xa0 arch_stack_walk+0x9d/0xf0 stack_trace_save+0x90/0xd0 kasan_save_stack+0x22/0x50 kasan_set_track+0x25/0x30 kasan_save_free_info+0x2b/0x50 __kasan_slab_free+0x10a/0x190 kmem_cache_free+0x10d/0x4d0 __vm_area_free+0x38/0x50 remove_vma+0x123/0x170 exit_mmap+0x332/0x8d0 mmput+0xd5/0x390 begin_new_exec+0x10b9/0x2fe0 load_elf_binary+0x80b/0x5030 bprm_execve+0x803/0x1940 do_execveat_common+0x734/0x8e0 __x64_sys_execve+0x93/0xc0 do_syscall_64+0x3f/0x90 entry_SYSCALL_64_after_hwframe+0x6e/0xd8 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/0x2bf0 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+0x8c8/0x2860 __do_softirq+0x1b7/0x7d4 irq_exit_rcu+0x93/0xc0 sysvec_apic_timer_interrupt+0x6e/0x90 asm_sysvec_apic_timer_interrupt+0x1a/0x20 _raw_spin_unlock_irqrestore+0x34/0x50 force_qs_rnp+0x1f8/0x6b0 rcu_gp_fqs_loop+0x45f/0xd50 rcu_gp_kthread+0x3d5/0x550 kthread+0x33f/0x440 ret_from_fork+0x2c/0x50 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+0x8c8/0x2860 __do_softirq+0x1b7/0x7d4 irq_exit_rcu+0x93/0xc0 sysvec_apic_timer_interrupt+0x6e/0x90 asm_sysvec_apic_timer_interrupt+0x1a/0x20 _raw_spin_unlock_irqrestore+0x34/0x50 force_qs_rnp+0x1f8/0x6b0 rcu_gp_fqs_loop+0x45f/0xd50 rcu_gp_kthread+0x3d5/0x550 kthread+0x33f/0x440 ret_from_fork+0x2c/0x50 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/0x2bf0 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+0x8c8/0x2860 __do_softirq+0x1b7/0x7d4 irq_exit_rcu+0x93/0xc0 sysvec_apic_timer_interrupt+0x6e/0x90 asm_sysvec_apic_timer_interrupt+0x1a/0x20 _raw_spin_unlock_irqrestore+0x34/0x50 force_qs_rnp+0x1f8/0x6b0 rcu_gp_fqs_loop+0x45f/0xd50 rcu_gp_kthread+0x3d5/0x550 kthread+0x33f/0x440 ret_from_fork+0x2c/0x50 stack backtrace: CPU: 0 PID: 14 Comm: rcu_preempt Not tainted 6.4.0-rc7-next-20230622 #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+0x8c8/0x2860 __do_softirq+0x1b7/0x7d4 irq_exit_rcu+0x93/0xc0 sysvec_apic_timer_interrupt+0x6e/0x90 asm_sysvec_apic_timer_interrupt+0x1a/0x20 RIP: 0010:_raw_spin_unlock_irqrestore+0x34/0x50 Code: c7 18 53 48 89 f3 48 8b 74 24 10 e8 56 16 da fc 48 89 ef e8 1e 94 da fc 80 e7 02 74 06 e8 44 e9 ff fc fb 65 ff 0d 14 03 b0 7b <74> 07 5b 5d e9 03 2a 00 00 0f 1f 44 00 00 5b 5d e9 f7 29 00 00 0f RSP: 0018:ffff888008da7cd0 EFLAGS: 00000286 RAX: 00000000002e5313 RBX: 0000000000000246 RCX: 1ffffffff0ba76e1 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff845387ac RBP: ffffffff856165c0 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff85d3e0d7 R11: 0000000000000001 R12: 0000000000000000 R13: ffffffff85616618 R14: dffffc0000000000 R15: ffffffff856165c0 force_qs_rnp+0x1f8/0x6b0 rcu_gp_fqs_loop+0x45f/0xd50 rcu_gp_kthread+0x3d5/0x550 kthread+0x33f/0x440 ret_from_fork+0x2c/0x50 ---------------- Code disassembly (best guess), 1 bytes skipped: 0: 18 53 48 sbb %dl,0x48(%rbx) 3: 89 f3 mov %esi,%ebx 5: 48 8b 74 24 10 mov 0x10(%rsp),%rsi a: e8 56 16 da fc callq 0xfcda1665 f: 48 89 ef mov %rbp,%rdi 12: e8 1e 94 da fc callq 0xfcda9435 17: 80 e7 02 and $0x2,%bh 1a: 74 06 je 0x22 1c: e8 44 e9 ff fc callq 0xfcffe965 21: fb sti 22: 65 ff 0d 14 03 b0 7b decl %gs:0x7bb00314(%rip) # 0x7bb0033d * 29: 74 07 je 0x32 <-- trapping instruction 2b: 5b pop %rbx 2c: 5d pop %rbp 2d: e9 03 2a 00 00 jmpq 0x2a35 32: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 37: 5b pop %rbx 38: 5d pop %rbp 39: e9 f7 29 00 00 jmpq 0x2a35 3e: 0f .byte 0xf