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INFO: rcu detected stall in generic_file_write_iter (2)

Status: upstream: reported on 2024/03/08 18:29
Reported-by: syzbot+bb21d42787b313521a4c@syzkaller.appspotmail.com
First crash: 55d, last: 2d10h
▶ ▼ Similar bugs (10)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in generic_file_write_iter (3) kernel 1 1611d 1611d 0/26 closed as invalid on 2019/12/04 14:04
upstream INFO: rcu detected stall in generic_file_write_iter (2) exfat 2 1826d 1865d 0/26 auto-closed as invalid on 2019/10/25 09:01
upstream BUG: soft lockup in generic_file_write_iter (2) mm 8 297d 285d 0/26 auto-obsoleted due to no activity on 2023/10/18 13:34
linux-5.15 INFO: rcu detected stall in generic_file_write_iter 1 241d 241d 0/3 auto-obsoleted due to no activity on 2023/12/13 17:16
upstream INFO: rcu detected stall in generic_file_write_iter (4) cgroups 1 1544d 1540d 0/26 auto-closed as invalid on 2020/05/09 11:43
upstream BUG: soft lockup in generic_file_write_iter net 2 483d 518d 0/26 auto-obsoleted due to no activity on 2023/04/05 19:12
upstream INFO: rcu detected stall in generic_file_write_iter mm 58 1890d 2032d 0/26 closed as dup on 2018/10/27 15:28
upstream INFO: rcu detected stall in generic_file_write_iter (5) fs 2 1379d 1386d 0/26 auto-closed as invalid on 2020/10/22 01:02
upstream INFO: rcu detected stall in generic_file_write_iter (6) cgroups mm 2 864d 921d 0/26 closed as invalid on 2022/02/08 09:50
linux-6.1 INFO: rcu detected stall in generic_file_write_iter 2 8d03h 11d 0/3 upstream: reported on 2024/04/21 16:23

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P5956/1:b..l
	(detected by 1, t=10503 jiffies, g=22073, q=13)
task:syz-executor.3  state:R  running task     stack:25432 pid: 5956 ppid:  5168 flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6780
 irqentry_exit+0x53/0x80 kernel/entry/common.c:432
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:lock_is_held_type+0x137/0x180
Code: 75 40 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 75 46 41 f7 c4 00 02 00 00 74 01 fb 65 48 8b 04 25 28 00 00 00 <48> 3b 44 24 08 75 3c 89 e8 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f
RSP: 0018:ffffc900032b7688 EFLAGS: 00000206
RAX: d65638cc96e8fb00 RBX: 0000000000000002 RCX: 0000000080000000
RDX: ffff888076df8000 RSI: ffffffff8a8b3c20 RDI: ffffffff8ad8f500
RBP: 0000000000000001 R08: ffffffff842f952d R09: fffffbfff1f7ee19
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000246
R13: ffff888076df8000 R14: 00000000ffffffff R15: ffffffff8c91fb20
 xa_entry include/linux/xarray.h:1182 [inline]
 xas_descend+0x118/0x3a0 lib/xarray.c:204
 xas_load+0xba/0x140 lib/xarray.c:240
 mapping_get_entry mm/filemap.c:1826 [inline]
 pagecache_get_page+0x20f/0x1010 mm/filemap.c:1894
 shmem_getpage_gfp+0x36c/0x3190 mm/shmem.c:1841
 shmem_getpage mm/shmem.c:151 [inline]
 shmem_write_begin+0xce/0x1a0 mm/shmem.c:2477
 generic_perform_write+0x2bf/0x5b0 mm/filemap.c:3785
 __generic_file_write_iter+0x243/0x4f0 mm/filemap.c:3912
 generic_file_write_iter+0xa7/0x1b0 mm/filemap.c:3944
 call_write_iter include/linux/fs.h:2172 [inline]
 new_sync_write fs/read_write.c:507 [inline]
 vfs_write+0xacf/0xe50 fs/read_write.c:594
 ksys_write+0x1a2/0x2c0 fs/read_write.c:647
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f5b377fcbef
RSP: 002b:00007f5b35d6fe80 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000001000000 RCX: 00007f5b377fcbef
RDX: 0000000001000000 RSI: 00007f5b2d950000 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000006125
R10: 0000000000000772 R11: 0000000000000293 R12: 0000000000000003
R13: 00007f5b35d6ff80 R14: 00007f5b35d6ff40 R15: 00007f5b2d950000
 </TASK>
rcu: rcu_preempt kthread starved for 10503 jiffies! g22073 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:R  running task     stack:27000 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
 schedule+0x11b/0x1f0 kernel/sched/core.c:6459
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x2bf/0x1080 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2145
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:300
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 1
CPU: 1 PID: 5966 Comm: syz-executor.4 Not tainted 5.15.157-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
 rcu_check_gp_kthread_starvation+0x1d2/0x240 kernel/rcu/tree_stall.h:487
 print_other_cpu_stall+0x137a/0x14d0 kernel/rcu/tree_stall.h:592
 check_cpu_stall kernel/rcu/tree_stall.h:745 [inline]
 rcu_pending kernel/rcu/tree.c:3932 [inline]
 rcu_sched_clock_irq+0xa38/0x1150 kernel/rcu/tree.c:2619
 update_process_times+0x196/0x200 kernel/time/timer.c:1818
 tick_sched_handle kernel/time/tick-sched.c:254 [inline]
 tick_sched_timer+0x386/0x550 kernel/time/tick-sched.c:1473
 __run_hrtimer kernel/time/hrtimer.c:1686 [inline]
 __hrtimer_run_queues+0x55b/0xcf0 kernel/time/hrtimer.c:1750
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline]
 __sysvec_apic_timer_interrupt+0x139/0x470 arch/x86/kernel/apic/apic.c:1102
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1096
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:csd_lock_wait kernel/smp.c:440 [inline]
RIP: 0010:smp_call_function_many_cond+0xa93/0xd90 kernel/smp.c:969
Code: 04 03 84 c0 0f 85 84 00 00 00 45 8b 7d 00 44 89 fe 83 e6 01 31 ff e8 4c cf 0b 00 41 83 e7 01 75 07 e8 e1 cb 0b 00 eb 41 f3 90 <48> b8 00 00 00 00 00 fc ff df 0f b6 04 03 84 c0 75 11 41 f7 45 00
RSP: 0018:ffffc90003307ac0 EFLAGS: 00000246
RAX: ffffffff81749124 RBX: 1ffff11017348509 RCX: 0000000000040000
RDX: ffffc9000c459000 RSI: 000000000003ffff RDI: 0000000000040000
RBP: ffffc90003307bf0 R08: ffffffff817490f4 R09: ffffed101736767b
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000000
R13: ffff8880b9a42848 R14: ffff8880b9b3b3c0 R15: 0000000000000001
 clock_was_set+0x7b6/0x880 kernel/time/hrtimer.c:974
 do_settimeofday64+0x673/0x7e0 kernel/time/timekeeping.c:1328
 __do_sys_clock_settime kernel/time/posix-timers.c:1124 [inline]
 __se_sys_clock_settime kernel/time/posix-timers.c:1112 [inline]
 __x64_sys_clock_settime+0x232/0x270 kernel/time/posix-timers.c:1112
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fd73d812ea9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 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 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fd73bd850c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e3
RAX: ffffffffffffffda RBX: 00007fd73d940f80 RCX: 00007fd73d812ea9
RDX: 0000000000000000 RSI: 0000000020000500 RDI: 0000000000000000
RBP: 00007fd73d85f4a4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007fd73d940f80 R15: 00007fff613886d8
 </TASK>

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/04/30 16:34 linux-5.15.y b925f60c6ee7 3ce4924c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2024/04/26 10:25 linux-5.15.y c52b9710c83d 8bdc0f22 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2024/03/08 18:28 linux-5.15.y 574362648507 8e75c913 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
* Struck through repros no longer work on HEAD.