audit: type=1804 audit(1555761973.955:354): pid=15997 uid=0 auid=4294967295 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 op=invalid_pcr cause=open_writers comm="syz-executor.3" name="/root/syzkaller-testdir720252269/syzkaller.nVEy86/3628/bus" dev="sda1" ino=16810 res=1 Enabling of bearer rejected, failed to enable media rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: (detected by 1, t=10502 jiffies, g=237509, q=88) rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4295097465-4295086963), jiffies_till_next_fqs=1, root ->qsmask 0x0 syz-executor.1 R running task 25984 15998 7798 0x00000000 Call Trace: sched_show_task kernel/sched/core.c:5297 [inline] sched_show_task.cold+0x292/0x30b kernel/sched/core.c:5272 print_other_cpu_stall kernel/rcu/tree.c:1430 [inline] check_cpu_stall kernel/rcu/tree.c:1557 [inline] __rcu_pending kernel/rcu/tree.c:3293 [inline] rcu_pending kernel/rcu/tree.c:3336 [inline] rcu_check_callbacks.cold+0xaa1/0xd93 kernel/rcu/tree.c:2682 update_process_times+0x32/0x80 kernel/time/timer.c:1636 tick_sched_handle+0xa2/0x190 kernel/time/tick-sched.c:164 tick_sched_timer+0x47/0x130 kernel/time/tick-sched.c:1274 __run_hrtimer kernel/time/hrtimer.c:1398 [inline] __hrtimer_run_queues+0x33e/0xde0 kernel/time/hrtimer.c:1460 hrtimer_interrupt+0x314/0x770 kernel/time/hrtimer.c:1518 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1029 [inline] smp_apic_timer_interrupt+0x120/0x570 arch/x86/kernel/apic/apic.c:1054 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:867 RIP: 0010:arch_local_save_flags arch/x86/include/asm/paravirt.h:783 [inline] RIP: 0010:arch_local_irq_save arch/x86/include/asm/paravirt.h:805 [inline] RIP: 0010:lock_acquire+0x85/0x3f0 kernel/locking/lockdep.c:3898 Code: 02 00 00 8b b3 7c 08 00 00 85 f6 0f 85 83 01 00 00 48 c7 c0 00 33 72 88 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 <0f> 85 f9 02 00 00 48 83 3d dd 8d 1f 07 00 0f 84 82 02 00 00 9c 58 RSP: 0018:ffff8880a8657378 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: 1ffffffff10e4660 RBX: ffff8880602ce640 RCX: 0000000000000002 RDX: dffffc0000000000 RSI: 0000000000000000 RDI: ffff8880602ceebc RBP: ffff8880a86573c0 R08: 0000000000000000 R09: 0000000000000000 R10: ffffed1015d24732 R11: 0000000000000000 R12: ffffffff8879d3e0 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000002 rcu_lock_acquire include/linux/rcupdate.h:244 [inline] rcu_read_lock include/linux/rcupdate.h:629 [inline] wb_get_create_current include/linux/backing-dev.h:300 [inline] balance_dirty_pages_ratelimited+0x73c/0x1f50 mm/page-writeback.c:1873 generic_perform_write+0x35a/0x530 mm/filemap.c:3175 __generic_file_write_iter+0x25e/0x630 mm/filemap.c:3264 ext4_file_write_iter+0x33f/0x11a0 fs/ext4/file.c:266 call_write_iter include/linux/fs.h:1811 [inline] do_iter_readv_writev+0x55d/0x830 fs/read_write.c:680 do_iter_write fs/read_write.c:959 [inline] do_iter_write+0x184/0x600 fs/read_write.c:940 vfs_iter_write+0x77/0xb0 fs/read_write.c:972 iter_file_splice_write+0x667/0xbe0 fs/splice.c:750 do_splice_from fs/splice.c:852 [inline] direct_splice_actor+0x126/0x1a0 fs/splice.c:1019 splice_direct_to_actor+0x2ea/0x890 fs/splice.c:974 do_splice_direct+0x1da/0x2a0 fs/splice.c:1062 do_sendfile+0x597/0xce0 fs/read_write.c:1446 __do_sys_sendfile64 fs/read_write.c:1507 [inline] __se_sys_sendfile64 fs/read_write.c:1493 [inline] __x64_sys_sendfile64+0x1dd/0x220 fs/read_write.c:1493 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x458c29 Code: ad b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f6668809c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000458c29 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 0000000000000007 RBP: 000000000073bfa0 R08: 0000000000000000 R09: 0000000000000000 R10: 00008000fffffffe R11: 0000000000000246 R12: 00007f666880a6d4 R13: 00000000004c5e10 R14: 00000000004da5c8 R15: 00000000ffffffff rcu: rcu_preempt kthread starved for 10502 jiffies! g237509 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0 rcu: RCU grace-period kthread stack dump: rcu_preempt R running task 29104 10 2 0x80000000 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x813/0x1d00 kernel/sched/core.c:3474 schedule+0x92/0x1c0 kernel/sched/core.c:3518 schedule_timeout+0x4db/0xfd0 kernel/time/timer.c:1804 rcu_gp_kthread+0xd5c/0x2190 kernel/rcu/tree.c:2202 kthread+0x357/0x430 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:413