INFO: rcu detected stall in sock_write_iter

Status: auto-obsoleted due to no activity on 2024/07/13 13:13
Reported-by: syzbot+9acc72b77117abad004c@syzkaller.appspotmail.com
First crash: 870d, last: 870d
▶ ▼ 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 12 6d04h 524d 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 69d 353d 0/2 upstream: reported C repro on 2025/09/03 11:54
upstream INFO: rcu detected stall in sock_write_iter mm 1 1 2454d 2454d 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 668d 668d 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 3 13d 88d 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 27d 837d 0/29 upstream: reported C repro on 2024/05/07 12:14
linux-5.15 INFO: rcu detected stall in sock_write_iter 1 1 1037d 1037d 0/3 auto-obsoleted due to no activity on 2024/01/28 05:21
linux-5.15 INFO: rcu detected stall in sock_write_iter (2) 1 1 855d 855d 0/3 auto-obsoleted due to no activity on 2024/07/28 08:46
upstream INFO: rcu detected stall in sock_write_iter (2) netfilter 1 1 1022d 1022d 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 215d 280d 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 528d 528d 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 739d 874d 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: 	1-...!: (0 ticks this GP) idle=8c1c/1/0x4000000000000000 softirq=57419/57419 fqs=0
	(detected by 0, t=10502 jiffies, g=79061, q=184 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 5519 Comm: syz-fuzzer Not tainted 6.1.84-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
RIP: 0010:__kasan_check_read+0x0/0x10 mm/kasan/shadow.c:31
Code: d8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 48 c7 c7 c5 9b 90 8c eb 0a 48 c7 c7 fd 9b 90 8c 4c 89 fe e8 9f 15 a6 08 31 db eb d7 cc cc <89> f6 48 8b 0c 24 31 d2 e9 d3 ec ff ff 0f 1f 00 89 f6 48 8b 0c 24
RSP: 0018:ffffc900001e0d58 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000000002 RCX: ffff8880134e5940
RDX: 0000000000010203 RSI: 0000000000000008 RDI: ffffffff8e736a28
RBP: ffffc900001e0eb0 R08: ffffffff8179b3f4 R09: ffffed1017325499
R10: 0000000000000000 R11: dffffc0000000001 R12: ffffffff88b45460
R13: 0000000000000001 R14: ffff8880b992a4c0 R15: 0000000000000001
FS:  000000c000172090(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4483252d58 CR3: 000000007d73e000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 instrument_atomic_read include/linux/instrumented.h:72 [inline]
 _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
 cpumask_test_cpu include/linux/cpumask.h:444 [inline]
 cpu_online include/linux/cpumask.h:1030 [inline]
 trace_hrtimer_expire_entry include/trace/events/timer.h:239 [inline]
 __run_hrtimer kernel/time/hrtimer.c:1683 [inline]
 __hrtimer_run_queues+0x50e/0xe50 kernel/time/hrtimer.c:1750
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1095 [inline]
 __sysvec_apic_timer_interrupt+0x156/0x580 arch/x86/kernel/apic/apic.c:1112
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1106
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653
RIP: 0010:__orc_find arch/x86/kernel/unwind_orc.c:50 [inline]
RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:178 [inline]
RIP: 0010:unwind_next_frame+0x477/0x2220 arch/x86/kernel/unwind_orc.c:448
Code: 01 c5 48 89 2d da 28 ad 0e 48 bf 00 00 00 00 00 fc ff df 0f 85 d7 00 00 00 e9 ad 00 00 00 4d 89 f4 4d 89 f7 48 89 e8 4c 29 f8 <48> 89 c1 48 c1 f9 02 48 c1 e8 3f 48 01 c8 48 83 e0 fe 49 8d 1c 47
RSP: 0018:ffffc9000493e7e0 EFLAGS: 00000202
RAX: 0000000000000020 RBX: ffffffff8ed4a9e8 RCX: ffffffff8ed4a9ec
RDX: ffffffff8f689744 RSI: ffffffff89095f7c RDI: dffffc0000000000
RBP: ffffffff8ed4a9e4 R08: 0000000000000014 R09: ffffc9000493e9b0
R10: 0000000000000000 R11: dffffc0000000001 R12: ffffffff8ed4a9c4
R13: ffffffff89095f7b R14: ffffffff8ed4a9c4 R15: ffffffff8ed4a9c4
 arch_stack_walk+0x10d/0x140 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x113/0x1c0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:516
 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236
 kasan_slab_free include/linux/kasan.h:177 [inline]
 slab_free_hook mm/slub.c:1724 [inline]
 slab_free_freelist_hook mm/slub.c:1750 [inline]
 slab_free mm/slub.c:3661 [inline]
 kmem_cache_free+0x292/0x510 mm/slub.c:3683
 packet_rcv+0x13b/0x12c0 net/packet/af_packet.c:2233
 dev_queue_xmit_nit+0xabc/0xbf0 net/core/dev.c:2322
 xmit_one net/core/dev.c:3623 [inline]
 dev_hard_start_xmit+0x142/0x8c0 net/core/dev.c:3643
 sch_direct_xmit+0x2b2/0x5e0 net/sched/sch_generic.c:342
 __dev_xmit_skb net/core/dev.c:3854 [inline]
 __dev_queue_xmit+0x1ace/0x3cf0 net/core/dev.c:4259
 dev_queue_xmit include/linux/netdevice.h:3021 [inline]
 neigh_hh_output include/net/neighbour.h:528 [inline]
 neigh_output include/net/neighbour.h:542 [inline]
 ip_finish_output2+0xcf2/0x1310 net/ipv4/ip_output.c:228
 dst_output include/net/dst.h:444 [inline]
 ip_local_out net/ipv4/ip_output.c:126 [inline]
 __ip_queue_xmit+0x11b1/0x1b60 net/ipv4/ip_output.c:532
 __tcp_transmit_skb+0x1e33/0x33a0 net/ipv4/tcp_output.c:1403
 tcp_transmit_skb net/ipv4/tcp_output.c:1421 [inline]
 tcp_write_xmit+0x1a60/0x64c0 net/ipv4/tcp_output.c:2709
 __tcp_push_pending_frames+0x97/0x350 net/ipv4/tcp_output.c:2894
 tcp_sendmsg_locked+0x37b2/0x4100 net/ipv4/tcp.c:1461
 tcp_sendmsg+0x2c/0x40 net/ipv4/tcp.c:1489
 sock_sendmsg_nosec net/socket.c:718 [inline]
 __sock_sendmsg net/socket.c:730 [inline]
 sock_write_iter+0x394/0x4e0 net/socket.c:1143
 call_write_iter include/linux/fs.h:2265 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x7ae/0xba0 fs/read_write.c:584
 ksys_write+0x19c/0x2c0 fs/read_write.c:637
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x40720e
Code: 48 83 ec 38 e8 13 00 00 00 48 83 c4 38 5d c3 cc cc cc cc cc cc cc cc cc cc 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:000000c000b915f8 EFLAGS: 00000206 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000040720e
RDX: 0000000000000004 RSI: 000000c0004a2200 RDI: 0000000000000003
RBP: 000000c000b91638 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 000000c000b91778
R13: 0000000000000005 R14: 000000c00011e820 R15: 0000000000000006
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g79061 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=30020
rcu: rcu_preempt kthread starved for 10502 jiffies! g79061 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:27032 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x142d/0x4550 kernel/sched/core.c:6558
 schedule+0xbf/0x180 kernel/sched/core.c:6634
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1965
 rcu_gp_fqs_loop+0x2d2/0x1120 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0xa3/0x3a0 kernel/rcu/tree.c:1905
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:307
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 5519 Comm: syz-fuzzer Not tainted 6.1.84-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
RIP: 0010:__lock_is_held kernel/locking/lockdep.c:5403 [inline]
RIP: 0010:lock_is_held_type+0xa4/0x180 kernel/locking/lockdep.c:5705
Code: 5e 78 75 41 83 bd d8 0a 00 00 00 7e 47 4c 89 ed 48 81 c5 e0 0a 00 00 31 db 48 83 fb 31 73 24 48 89 ef 4c 89 fe e8 1c 02 00 00 <85> c0 75 2a 48 ff c3 49 63 85 d8 0a 00 00 48 83 c5 28 48 39 c3 7c
RSP: 0018:ffffc900001e0c78 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffff8880134e5940
RDX: ffff8880134e5940 RSI: ffff88801ee87300 RDI: ffff8880134e6448
RBP: ffff8880134e6448 R08: ffffffff88b4551e R09: 0000000000000003
R10: ffffffffffffffff R11: dffffc0000000001 R12: 0000000000000046
R13: ffff8880134e5940 R14: 00000000ffffffff R15: ffff88801ee87300
FS:  000000c000172090(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4483252d58 CR3: 000000007d73e000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 lock_is_held include/linux/lockdep.h:283 [inline]
 advance_sched+0xd0/0x970 net/sched/sch_taprio.c:703
 __run_hrtimer kernel/time/hrtimer.c:1686 [inline]
 __hrtimer_run_queues+0x5e5/0xe50 kernel/time/hrtimer.c:1750
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1095 [inline]
 __sysvec_apic_timer_interrupt+0x156/0x580 arch/x86/kernel/apic/apic.c:1112
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1106
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653
RIP: 0010:__orc_find arch/x86/kernel/unwind_orc.c:50 [inline]
RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:178 [inline]
RIP: 0010:unwind_next_frame+0x477/0x2220 arch/x86/kernel/unwind_orc.c:448
Code: 01 c5 48 89 2d da 28 ad 0e 48 bf 00 00 00 00 00 fc ff df 0f 85 d7 00 00 00 e9 ad 00 00 00 4d 89 f4 4d 89 f7 48 89 e8 4c 29 f8 <48> 89 c1 48 c1 f9 02 48 c1 e8 3f 48 01 c8 48 83 e0 fe 49 8d 1c 47
RSP: 0018:ffffc9000493e7e0 EFLAGS: 00000202
RAX: 0000000000000020 RBX: ffffffff8ed4a9e8 RCX: ffffffff8ed4a9ec
RDX: ffffffff8f689744 RSI: ffffffff89095f7c RDI: dffffc0000000000
RBP: ffffffff8ed4a9e4 R08: 0000000000000014 R09: ffffc9000493e9b0
R10: 0000000000000000 R11: dffffc0000000001 R12: ffffffff8ed4a9c4
R13: ffffffff89095f7b R14: ffffffff8ed4a9c4 R15: ffffffff8ed4a9c4
 arch_stack_walk+0x10d/0x140 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x113/0x1c0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:516
 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236
 kasan_slab_free include/linux/kasan.h:177 [inline]
 slab_free_hook mm/slub.c:1724 [inline]
 slab_free_freelist_hook mm/slub.c:1750 [inline]
 slab_free mm/slub.c:3661 [inline]
 kmem_cache_free+0x292/0x510 mm/slub.c:3683
 packet_rcv+0x13b/0x12c0 net/packet/af_packet.c:2233
 dev_queue_xmit_nit+0xabc/0xbf0 net/core/dev.c:2322
 xmit_one net/core/dev.c:3623 [inline]
 dev_hard_start_xmit+0x142/0x8c0 net/core/dev.c:3643
 sch_direct_xmit+0x2b2/0x5e0 net/sched/sch_generic.c:342
 __dev_xmit_skb net/core/dev.c:3854 [inline]
 __dev_queue_xmit+0x1ace/0x3cf0 net/core/dev.c:4259
 dev_queue_xmit include/linux/netdevice.h:3021 [inline]
 neigh_hh_output include/net/neighbour.h:528 [inline]
 neigh_output include/net/neighbour.h:542 [inline]
 ip_finish_output2+0xcf2/0x1310 net/ipv4/ip_output.c:228
 dst_output include/net/dst.h:444 [inline]
 ip_local_out net/ipv4/ip_output.c:126 [inline]
 __ip_queue_xmit+0x11b1/0x1b60 net/ipv4/ip_output.c:532
 __tcp_transmit_skb+0x1e33/0x33a0 net/ipv4/tcp_output.c:1403
 tcp_transmit_skb net/ipv4/tcp_output.c:1421 [inline]
 tcp_write_xmit+0x1a60/0x64c0 net/ipv4/tcp_output.c:2709
 __tcp_push_pending_frames+0x97/0x350 net/ipv4/tcp_output.c:2894
 tcp_sendmsg_locked+0x37b2/0x4100 net/ipv4/tcp.c:1461
 tcp_sendmsg+0x2c/0x40 net/ipv4/tcp.c:1489
 sock_sendmsg_nosec net/socket.c:718 [inline]
 __sock_sendmsg net/socket.c:730 [inline]
 sock_write_iter+0x394/0x4e0 net/socket.c:1143
 call_write_iter include/linux/fs.h:2265 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x7ae/0xba0 fs/read_write.c:584
 ksys_write+0x19c/0x2c0 fs/read_write.c:637
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x40720e
Code: 48 83 ec 38 e8 13 00 00 00 48 83 c4 38 5d c3 cc cc cc cc cc cc cc cc cc cc 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:000000c000b915f8 EFLAGS: 00000206 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000040720e
RDX: 0000000000000004 RSI: 000000c0004a2200 RDI: 0000000000000003
RBP: 000000c000b91638 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 000000c000b91778
R13: 0000000000000005 R14: 000000c00011e820 R15: 0000000000000006
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/04/04 13:12 linux-6.1.y 347385861c50 0ee3535e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sock_write_iter
* Struck through repros no longer work on HEAD.