rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: (detected by 1, t=10502 jiffies, g=6221, q=39) rcu: All QSes seen, last rcu_preempt kthread activity 10503 (4295053756-4295043253), jiffies_till_next_fqs=1, root ->qsmask 0x0 syz-executor551 R running task 22976 8244 8242 0x00004000 Call Trace: sched_show_task+0x3bd/0x490 kernel/sched/core.c:5286 print_other_cpu_stall kernel/rcu/tree_stall.h:410 [inline] check_cpu_stall kernel/rcu/tree_stall.h:536 [inline] rcu_pending kernel/rcu/tree.c:2625 [inline] rcu_sched_clock_irq+0x1607/0x1740 kernel/rcu/tree.c:2161 update_process_times+0x134/0x190 kernel/time/timer.c:1639 tick_sched_handle kernel/time/tick-sched.c:167 [inline] tick_sched_timer+0x257/0x410 kernel/time/tick-sched.c:1298 __run_hrtimer kernel/time/hrtimer.c:1389 [inline] __hrtimer_run_queues+0x471/0x8b0 kernel/time/hrtimer.c:1451 hrtimer_interrupt+0x38c/0xda0 kernel/time/hrtimer.c:1509 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1041 [inline] smp_apic_timer_interrupt+0xee/0x260 arch/x86/kernel/apic/apic.c:1066 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:806 RIP: 0010:__find_get_block+0x235/0x1080 fs/buffer.c:1294 Code: fc ff df 80 3c 08 00 74 0c 48 c7 c7 a0 63 aa 88 e8 a0 a6 e8 ff 48 83 3d 08 2f e4 06 00 0f 84 d9 0d 00 00 fb 66 0f 1f 44 00 00 <48> 85 db 74 50 e8 41 7d af ff 48 89 df e8 d9 d6 ff ff 49 89 de 48 RSP: 0018:ffff888097faedd8 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13 RAX: 1ffffffff1154c74 RBX: ffff88809137abd0 RCX: dffffc0000000000 RDX: dffffc0000000000 RSI: ffff88808ee6ade8 RDI: ffff88808ee6ad68 RBP: ffff888097faee38 R08: ffff88808ee6ad80 R09: ffffed101226f587 R10: ffffed101226f587 R11: 1ffff1101226f586 R12: 0000000000031528 R13: 0000000000000000 R14: 0000000000001000 R15: 0000000000000001 __getblk_gfp+0x30/0x9c0 fs/buffer.c:1318 sb_getblk include/linux/buffer_head.h:325 [inline] __ext4_get_inode_loc+0x37b/0xcb0 fs/ext4/inode.c:4594 ext4_get_inode_loc fs/ext4/inode.c:4707 [inline] ext4_reserve_inode_write+0xe9/0x220 fs/ext4/inode.c:5888 ext4_mark_inode_dirty+0x102/0x790 fs/ext4/inode.c:6040 ext4_dirty_inode+0x8b/0xb0 fs/ext4/inode.c:6079 __mark_inode_dirty+0xbf/0x700 fs/fs-writeback.c:2161 mark_inode_dirty include/linux/fs.h:2137 [inline] __generic_write_end fs/buffer.c:2118 [inline] generic_write_end+0x151/0x320 fs/buffer.c:2162 ext4_da_write_end+0x72e/0x8a0 fs/ext4/inode.c:3201 generic_perform_write+0x3ac/0x550 mm/filemap.c:3217 __generic_file_write_iter+0x24b/0x520 mm/filemap.c:3335 ext4_file_write_iter+0x902/0x12e0 fs/ext4/file.c:266 do_iter_readv_writev+0x6f5/0x9c0 include/linux/fs.h:1866 do_iter_write+0x180/0x590 fs/read_write.c:970 vfs_iter_write+0x7c/0xa0 fs/read_write.c:983 iter_file_splice_write+0x79f/0xf40 fs/splice.c:746 do_splice_from fs/splice.c:848 [inline] direct_splice_actor+0xf7/0x130 fs/splice.c:1020 splice_direct_to_actor+0x4c6/0xb40 fs/splice.c:975 do_splice_direct+0x279/0x3d0 fs/splice.c:1063 do_sendfile+0x8a3/0x1110 fs/read_write.c:1464 __do_sys_sendfile64 fs/read_write.c:1519 [inline] __se_sys_sendfile64 fs/read_write.c:1511 [inline] __x64_sys_sendfile64+0x13b/0x220 fs/read_write.c:1511 do_syscall_64+0xfe/0x140 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4417c9 Code: e8 7c e7 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00 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 0f 83 bb 07 fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffda91c5b38 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007ffda91c5ce0 RCX: 00000000004417c9 RDX: 0000000020000000 RSI: 0000000000000003 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 00008080fffffffe R11: 0000000000000246 R12: 0000000000000000 R13: 00000000004024a0 R14: 0000000000000000 R15: 0000000000000000 rcu: rcu_preempt kthread starved for 10566 jiffies! g6221 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0 rcu: RCU grace-period kthread stack dump: rcu_preempt R running task 26336 10 2 0x80004000 Call Trace: context_switch kernel/sched/core.c:2818 [inline] __schedule+0x658/0x9e0 kernel/sched/core.c:3445 schedule+0x131/0x1d0 kernel/sched/core.c:3509 schedule_timeout+0x19d/0x2b0 kernel/time/timer.c:1807 rcu_gp_fqs_loop kernel/rcu/tree.c:1589 [inline] rcu_gp_kthread+0xfd8/0x1880 kernel/rcu/tree.c:1746 kthread+0x325/0x350 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352