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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: 638d, last: 3d11h
▶ ▼ Similar bugs (13)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in generic_file_write_iter (3) mm 1 1 2194d 2194d 0/29 closed as invalid on 2019/12/04 14:04
upstream INFO: rcu detected stall in generic_file_write_iter (2) exfat 1 2 2409d 2448d 0/29 auto-closed as invalid on 2019/10/25 09:01
upstream BUG: soft lockup in generic_file_write_iter (2) mm 1 8 880d 868d 0/29 auto-obsoleted due to no activity on 2023/10/18 13:34
linux-6.1 INFO: rcu detected stall in generic_file_write_iter (2) 1 12 18h38m 352d 0/3 upstream: reported on 2024/12/19 01:50
linux-5.15 INFO: rcu detected stall in generic_file_write_iter 1 1 824d 824d 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 1 2127d 2123d 0/29 auto-closed as invalid on 2020/05/09 11:43
upstream BUG: soft lockup in generic_file_write_iter net mm fs 1 2 1066d 1100d 0/29 auto-obsoleted due to no activity on 2023/04/05 19:12
upstream INFO: rcu detected stall in generic_file_write_iter mm 1 58 2473d 2615d 0/29 closed as dup on 2018/10/27 15:28
upstream INFO: rcu detected stall in generic_file_write_iter (5) fs 1 2 1961d 1969d 0/29 auto-closed as invalid on 2020/10/22 01:02
upstream INFO: rcu detected stall in generic_file_write_iter (7) block 1 1 146d 146d 0/29 auto-obsoleted due to no activity on 2025/10/11 00:51
upstream INFO: rcu detected stall in generic_file_write_iter (6) cgroups mm 1 2 1447d 1504d 0/29 closed as invalid on 2022/02/08 09:50
linux-6.1 INFO: rcu detected stall in generic_file_write_iter 1 18 481d 594d 0/3 auto-obsoleted due to no activity on 2024/11/12 08:46
android-5-15 BUG: soft lockup in generic_file_write_iter 1 1 573d 573d 0/2 auto-obsoleted due to no activity on 2024/08/10 08:10

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P6956/1:b..l
	(detected by 1, t=10502 jiffies, g=22741, q=22)
task:syz.4.573       state:R  running task     stack:24040 pid: 6956 ppid:  4191 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11bb/0x4390 kernel/sched/core.c:6395
 preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6799
 irqentry_exit+0x63/0x70 kernel/entry/common.c:432
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:lock_acquire+0x1f2/0x3f0 kernel/locking/lockdep.c:5627
Code: 00 9c 8f 84 24 80 00 00 00 f6 84 24 81 00 00 00 02 0f 85 f6 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 44 3d 00 00 00 00 00 66 43 c7 44 3d 09 00 00 43 c6 44 3d 0b
RSP: 0018:ffffc900032a7640 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 33ffb08c1c052e00
RDX: 0000000000000000 RSI: ffffffff8a0b2f00 RDI: ffffffff8a59e580
RBP: ffffc900032a7750 R08: dffffc0000000000 R09: fffffbfff1ff7c19
R10: fffffbfff1ff7c19 R11: 1ffffffff1ff7c18 R12: ffffffff8c11c760
R13: 1ffff92000654ed4 R14: 0000000000000246 R15: dffffc0000000000
 rcu_lock_acquire+0x20/0x30 include/linux/rcupdate.h:313
 rcu_read_lock include/linux/rcupdate.h:740 [inline]
 percpu_ref_put_many include/linux/percpu-refcount.h:317 [inline]
 percpu_ref_put+0x16/0x150 include/linux/percpu-refcount.h:338
 css_put include/linux/cgroup.h:405 [inline]
 __mem_cgroup_charge+0x52/0x80 mm/memcontrol.c:6802
 mem_cgroup_charge include/linux/memcontrol.h:700 [inline]
 shmem_add_to_page_cache+0xa83/0x14b0 mm/shmem.c:718
 shmem_getpage_gfp+0x1793/0x2d40 mm/shmem.c:1940
 shmem_getpage mm/shmem.c:151 [inline]
 shmem_write_begin+0xcd/0x1a0 mm/shmem.c:2474
 generic_perform_write+0x2aa/0x530 mm/filemap.c:3785
 __generic_file_write_iter+0x25f/0x4e0 mm/filemap.c:3912
 generic_file_write_iter+0xa6/0x1b0 mm/filemap.c:3944
 call_write_iter include/linux/fs.h:2173 [inline]
 new_sync_write fs/read_write.c:507 [inline]
 vfs_write+0x712/0xd00 fs/read_write.c:594
 ksys_write+0x14d/0x250 fs/read_write.c:647
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f6b022071ff
RSP: 002b:00007f6b0046edf0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000001000000 RCX: 00007f6b022071ff
RDX: 0000000001000000 RSI: 00007f6af804f000 RDI: 000000000000000a
RBP: 0000000000000000 R08: 0000000000000000 R09: 00000000000097e8
R10: 0000000000000002 R11: 0000000000000293 R12: 000000000000000a
R13: 00007f6b0046eef0 R14: 00007f6b0046eeb0 R15: 00007f6af804f000
 </TASK>
rcu: rcu_preempt kthread starved for 10538 jiffies! g22741 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:27296 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11bb/0x4390 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x29e/0x11b0 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0x98/0x350 kernel/rcu/tree.c:2145
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 1
CPU: 1 PID: 0 Comm: swapper/1 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
 <IRQ>
 dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
 rcu_check_gp_kthread_starvation+0x1cd/0x250 kernel/rcu/tree_stall.h:487
 print_other_cpu_stall+0x10c8/0x1220 kernel/rcu/tree_stall.h:592
 check_cpu_stall kernel/rcu/tree_stall.h:745 [inline]
 rcu_pending kernel/rcu/tree.c:3936 [inline]
 rcu_sched_clock_irq+0x831/0x1110 kernel/rcu/tree.c:2619
 update_process_times+0x193/0x200 kernel/time/timer.c:1818
 tick_sched_handle kernel/time/tick-sched.c:254 [inline]
 tick_sched_timer+0x37d/0x560 kernel/time/tick-sched.c:1473
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x4fe/0xc40 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
 __sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:default_idle+0xb/0x10 arch/x86/kernel/process.c:730
Code: bf 48 89 df e8 66 76 09 f8 eb b5 e8 9f af f6 ff 00 00 cc cc 00 00 cc cc 00 00 cc cc 00 00 cc 66 90 0f 00 2d 37 06 53 00 fb f4 <c3> 0f 1f 40 00 41 57 41 56 53 49 be 00 00 00 00 00 fc ff df 65 48
RSP: 0018:ffffc90000d67d48 EFLAGS: 000002c2
RAX: 7ea2ef4c05242200 RBX: ffff88813fe48000 RCX: 7ea2ef4c05242200
RDX: 0000000000000001 RSI: ffffffff8a0b1c60 RDI: ffffffff8a59e580
RBP: ffffc90000d67e80 R08: dffffc0000000000 R09: ffffed1017227662
R10: ffffed1017227662 R11: 1ffff11017227661 R12: ffffffff8d699d28
R13: 0000000000000001 R14: 0000000000000001 R15: 1ffff11027fc9000
 default_idle_call+0x81/0xc0 kernel/sched/idle.c:112
 cpuidle_idle_call kernel/sched/idle.c:194 [inline]
 do_idle+0x21b/0x5b0 kernel/sched/idle.c:306
 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:403
 start_secondary+0x31f/0x430 arch/x86/kernel/smpboot.c:281
 secondary_startup_64_no_verify+0xb1/0xbb
 </TASK>

Crashes (32):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/12/03 13:08 linux-5.15.y cc5ec8769306 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2025/11/10 14:27 linux-5.15.y cc5ec8769306 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2025/11/03 17:59 linux-5.15.y cc5ec8769306 2c50b6a9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2025/11/02 05:02 linux-5.15.y cc5ec8769306 2c50b6a9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2025/08/17 10:48 linux-5.15.y c79648372d02 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in generic_file_write_iter
2025/08/14 23:36 linux-5.15.y c79648372d02 5d8c2ac2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2025/08/12 10:31 linux-5.15.y c79648372d02 c06e8995 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in generic_file_write_iter
2025/07/17 15:48 linux-5.15.y 89950c454265 0d1223f1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2025/04/21 19:41 linux-5.15.y f7347f400572 2a20f901 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2025/03/19 01:25 linux-5.15.y 0c935c049b5c 22a6c2b1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2025/02/07 09:54 linux-5.15.y c16c81c81336 53657d1b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2025/01/05 20:37 linux-5.15.y 91786f140358 f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2024/11/25 11:35 linux-5.15.y 0a51d2d4527b 68da6d95 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2024/10/04 02:05 linux-5.15.y 3a5928702e71 d7906eff .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2024/10/01 02:03 linux-5.15.y 3a5928702e71 bbd4e0a4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2024/09/25 05:30 linux-5.15.y 3a5928702e71 5643e0e9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2024/09/25 05:25 linux-5.15.y 3a5928702e71 5643e0e9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2024/08/25 12:46 linux-5.15.y fa93fa65db6e d7d32352 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2024/08/23 15:54 linux-5.15.y fa93fa65db6e d7d32352 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2024/08/14 05:45 linux-5.15.y 7e89efd3ae1c bde81f6f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2024/08/11 14:11 linux-5.15.y 7e89efd3ae1c 6f4edef4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2024/08/06 05:48 linux-5.15.y 7e89efd3ae1c e1bdb00a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2024/07/02 15:21 linux-5.15.y 4878aadf2d15 07f0a0a0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2024/06/26 23:11 linux-5.15.y 4878aadf2d15 c6d33a01 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2024/06/20 01:11 linux-5.15.y 4878aadf2d15 41b7e219 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2024/06/19 05:21 linux-5.15.y 4878aadf2d15 41b7e219 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2024/06/19 01:58 linux-5.15.y 4878aadf2d15 639d6cdf .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2024/05/24 04:21 linux-5.15.y 83655231580b 8f98448e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in generic_file_write_iter
2024/04/30 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
2024/08/29 09:14 linux-5.15.y fa93fa65db6e ef3de9e8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 INFO: rcu detected stall in generic_file_write_iter
* Struck through repros no longer work on HEAD.