INFO: rcu detected stall in sock_write_iter

Status: auto-obsoleted due to no activity on 2024/01/28 05:21
Reported-by: syzbot+71975e303a56d5d77b8a@syzkaller.appspotmail.com
First crash: 1023d, last: 1023d
▶ ▼ Similar bugs (12)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 INFO: rcu detected stall in sock_write_iter (4) origin:lts-only 1 syz done 11 19d 510d 0/3 upstream: reported syz repro on 2025/03/16 07:14
linux-6.6 INFO: rcu detected stall in sock_write_iter origin:upstream missing-backport 1 syz, C inconclusive 12 55d 339d 0/2 upstream: reported C repro on 2025/09/03 11:54
upstream INFO: rcu detected stall in sock_write_iter mm 1 1 2439d 2439d 0/29 closed as invalid on 2019/12/04 14:04
linux-5.15 INFO: rcu detected stall in sock_write_iter (3) 1 1 654d 654d 0/3 auto-obsoleted due to no activity on 2025/01/31 00:48
linux-6.1 INFO: rcu detected stall in sock_write_iter (3) 1 2 20d 74d 0/3 upstream: reported on 2026/05/26 07:14
upstream INFO: rcu detected stall in sock_write_iter (3) net prio:low 1 syz, C done error 221 13d 823d 0/29 upstream: reported C repro on 2024/05/07 12:14
linux-5.15 INFO: rcu detected stall in sock_write_iter (2) 1 1 841d 841d 0/3 auto-obsoleted due to no activity on 2024/07/28 08:46
linux-6.1 INFO: rcu detected stall in sock_write_iter 1 1 855d 855d 0/3 auto-obsoleted due to no activity on 2024/07/13 13:13
upstream INFO: rcu detected stall in sock_write_iter (2) netfilter 1 1 1008d 1008d 0/29 auto-obsoleted due to no activity on 2024/01/03 00:51
linux-6.1 INFO: rcu detected stall in sock_write_iter (2) 1 2 201d 265d 0/3 auto-obsoleted due to no activity on 2026/04/29 05:14
android-5-10 BUG: soft lockup in sock_write_iter 1 1 514d 514d 0/2 auto-obsoleted due to no activity on 2025/06/10 11:55
android-5-15 BUG: soft lockup in sock_write_iter 1 24 724d 860d 0/2 auto-obsoleted due to no activity on 2024/11/03 03:04

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (0 ticks this GP) idle=395/1/0x4000000000000000 softirq=84797/84797 fqs=5 
	(detected by 1, t=10504 jiffies, g=139793, q=201)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 3815 Comm: syz-fuzzer Not tainted 5.15.136-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023
RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline]
RIP: 0010:check_kcov_mode kernel/kcov.c:163 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:218 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0xc/0x80 kernel/kcov.c:284
Code: 08 03 00 00 00 48 89 44 0a 10 48 89 74 0a 18 4c 89 44 0a 20 49 ff c1 4c 89 09 c3 0f 1f 00 4c 8b 04 24 65 48 8b 15 04 4a 82 7e <65> 8b 05 05 4a 82 7e a9 00 01 ff 00 74 10 a9 00 01 00 00 74 5b 83
RSP: 0018:ffffc90000007cb8 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 0000000000000001 RCX: ffff888073b1bb80
RDX: ffff888073b1bb80 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffff8880401a02e8 R08: ffffffff886a1c68 R09: 0000000000000003
R10: ffffffffffffffff R11: dffffc0000000001 R12: ffff8880401a0000
R13: ffff8880401a0340 R14: dffffc0000000000 R15: ffff8880401a0328
FS:  000000c0172a4890(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0a19a66038 CR3: 000000007088f000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 advance_sched+0x148/0x940 net/sched/sch_taprio.c:721
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x598/0xcf0 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1811
 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:_compound_head include/linux/page-flags.h:198 [inline]
RIP: 0010:virt_to_head_page include/linux/mm.h:902 [inline]
RIP: 0010:kmem_cache_free+0x4f/0x1f0 mm/slub.c:3515
Code: 85 c0 0f 84 1d 01 00 00 49 89 c7 48 bb 00 00 00 00 00 ea ff ff 4c 89 f7 e8 fe 6b 70 ff 48 c1 e8 0c 48 c1 e0 06 4c 8b 6c 18 08 <41> f6 c5 01 0f 85 10 01 00 00 48 01 c3 49 89 dd 4c 8b 64 24 60 4c
RSP: 0018:ffffc900048df518 EFLAGS: 00000202
RAX: 0000000001d55140 RBX: ffffea0000000000 RCX: ffff888073b1bb80
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900048df8d0 R08: ffffffff81396b08 R09: ffffed100eaa8bab
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: ffffea0001d55101 R14: ffff888075545b80 R15: ffff8880169a7640
 tcp_clean_rtx_queue net/ipv4/tcp_input.c:3341 [inline]
 tcp_ack+0x22ea/0x6a80 net/ipv4/tcp_input.c:3894
 tcp_rcv_established+0xf2d/0x1e20 net/ipv4/tcp_input.c:5897
 tcp_v4_do_rcv+0x423/0x960 net/ipv4/tcp_ipv4.c:1727
 sk_backlog_rcv include/net/sock.h:1059 [inline]
 __release_sock+0x198/0x4b0 net/core/sock.c:2705
 release_sock+0x5d/0x1c0 net/core/sock.c:3246
 tcp_sendmsg+0x36/0x40 net/ipv4/tcp.c:1463
 sock_sendmsg_nosec net/socket.c:704 [inline]
 __sock_sendmsg net/socket.c:716 [inline]
 sock_write_iter+0x39b/0x530 net/socket.c:1077
 call_write_iter include/linux/fs.h:2103 [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+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x403ace
Code: 48 89 6c 24 38 48 8d 6c 24 38 e8 0d 00 00 00 48 8b 6c 24 38 48 83 c4 40 c3 cc cc cc 49 89 f2 48 89 fa 48 89 ce 48 89 df 0f 05 <48> 3d 01 f0 ff ff 76 15 48 f7 d8 48 89 c1 48 c7 c0 ff ff ff ff 48
RSP: 002b:000000c0008cf120 EFLAGS: 00000206 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000403ace
RDX: 00000000000000f0 RSI: 000000c000220200 RDI: 0000000000000003
RBP: 000000c0008cf160 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 000000c0008cf2a0
R13: 0000000000000000 R14: 000000c00f3fc340 R15: 000000c0000a6900
 </TASK>
rcu: rcu_preempt kthread starved for 10475 jiffies! g139793 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:26712 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5026 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6372
 schedule+0x11b/0x1f0 kernel/sched/core.c:6455
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1884
 rcu_gp_fqs_loop+0x2af/0xf70 kernel/rcu/tree.c:1959
 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2132
 kthread+0x3f6/0x4f0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 1
CPU: 1 PID: 25825 Comm: kworker/1:25 Not tainted 5.15.136-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023
Workqueue: events bpf_prog_free_deferred
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb 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:481
 print_other_cpu_stall+0x137a/0x14d0 kernel/rcu/tree_stall.h:586
 check_cpu_stall kernel/rcu/tree_stall.h:729 [inline]
 rcu_pending kernel/rcu/tree.c:3911 [inline]
 rcu_sched_clock_irq+0x94f/0x1770 kernel/rcu/tree.c:2606
 update_process_times+0x196/0x200 kernel/time/timer.c:1788
 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:1685 [inline]
 __hrtimer_run_queues+0x55b/0xcf0 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1811
 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 3c c6 0b 00 41 83 e7 01 75 07 e8 d1 c2 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:ffffc90004d278a0 EFLAGS: 00000293
RAX: ffffffff81745fa4 RBX: 1ffff110173483c1 RCX: ffff888027e38000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90004d279e0 R08: ffffffff81745f74 R09: fffffbfff1f79a22
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000000
R13: ffff8880b9a41e08 R14: ffff8880b9b3a780 R15: 0000000000000001
 on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1135
 __purge_vmap_area_lazy+0x294/0x1740 mm/vmalloc.c:1683
 _vm_unmap_aliases+0x453/0x4e0 mm/vmalloc.c:2107
 vm_remove_mappings mm/vmalloc.c:2584 [inline]
 __vunmap+0x72e/0xa20 mm/vmalloc.c:2611
 bpf_jit_binary_free kernel/bpf/core.c:910 [inline]
 bpf_jit_free+0x92/0x180 kernel/bpf/core.c:923
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/10/20 05:20 linux-5.15.y 00c03985402e a42250d2 .config console log report info ci2-linux-5-15-kasan INFO: rcu detected stall in sock_write_iter
* Struck through repros no longer work on HEAD.