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WARNING in rcu_check_gp_start_stall

Status: upstream: reported C repro on 2019/02/22 17:10
Subsystems: net
[Documentation on labels]
Reported-by: syzbot+111bc509cd9740d7e4aa@syzkaller.appspotmail.com
First crash: 2448d, last: 9h41m
Cause bisection: introduced by (bisect log) :
commit f1e3e92135202ff3d95195393ee62808c109208c
Author: Malcolm Priestley <tvboxspy@gmail.com>
Date: Wed Jul 22 18:16:42 2015 +0000

  staging: vt6655: fix tagSRxDesc -> next_desc type

Crash: INFO: rcu detected stall in corrupted (log)
Repro: C syz .config
  
Fix bisection: failed (error log, bisect log)
  
▶ ▼ Discussions (12)
Title Replies (including bot) Last reply
[syzbot] Monthly net report (Oct 2025) 0 (1) 2025/10/16 08:36
[syzbot] Monthly net report (Sep 2025) 0 (1) 2025/09/15 06:54
[syzbot] Monthly net report (Aug 2025) 0 (1) 2025/08/14 12:42
[syzbot] Monthly net report (Jul 2025) 0 (1) 2025/07/14 07:23
[syzbot] Monthly net report (Jun 2025) 0 (1) 2025/06/13 12:25
[syzbot] Monthly net report (Nov 2024) 0 (1) 2024/11/04 08:49
[syzbot] Monthly net report (Oct 2024) 0 (1) 2024/10/03 09:02
[syzbot] Monthly net report (Sep 2024) 0 (1) 2024/09/02 08:21
[syzbot] Monthly net report (Aug 2024) 0 (1) 2024/08/02 07:26
[syzbot] Monthly net report (Jul 2024) 0 (1) 2024/07/01 10:28
[syzbot] Monthly mm report (May 2023) 0 (1) 2023/05/03 07:26
WARNING in rcu_check_gp_start_stall 7 (9) 2019/03/18 12:18
▶ ▼ Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 WARNING in rcu_check_gp_start_stall (3) -1 5 6d07h 125d 0/3 upstream: reported on 2025/07/02 22:12
linux-6.6 WARNING in rcu_check_gp_start_stall origin:lts-only -1 C done 87 4h44m 141d 0/2 upstream: reported C repro on 2025/06/17 13:49
linux-5.15 WARNING in rcu_check_gp_start_stall (2) -1 7 415d 559d 0/3 auto-obsoleted due to no activity on 2024/12/25 11:45
linux-5.15 WARNING in rcu_check_gp_start_stall -1 1 698d 698d 0/3 auto-obsoleted due to no activity on 2024/03/17 09:39
linux-6.1 WARNING in rcu_check_gp_start_stall origin:upstream missing-backport -1 C done 19 35d 780d 0/3 upstream: reported C repro on 2023/09/17 20:24
▶ ▼ Last patch testing requests (10)
Created Duration User Patch Repo Result
2025/08/20 15:53 24m retest repro net OK log
2025/08/20 15:53 25m retest repro net OK log
2025/08/20 15:53 21m retest repro net report log
2025/08/20 15:53 22m retest repro net report log
2025/08/20 15:53 19m retest repro net report log
2025/08/20 12:53 23m retest repro upstream OK log
2025/08/20 12:53 39m retest repro upstream OK log
2025/08/20 12:53 26m retest repro upstream OK log
2025/08/20 11:24 24m retest repro upstream report log
2025/08/20 09:53 41m retest repro net-next report log
▶ ▼ Fix bisection attempts (5)
Created Duration User Patch Repo Result
2020/05/17 02:11 0m bisect fix upstream error job log
2020/04/16 22:09 21m bisect fix upstream OK (0) job log log
2020/03/17 16:07 23m bisect fix upstream OK (0) job log log
2020/02/16 08:59 23m bisect fix upstream OK (0) job log log
2019/12/16 21:03 22m bisect fix upstream OK (0) job log log

Sample crash report:
bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0)
bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
------------[ cut here ]------------
WARNING: CPU: 1 PID: 24 at kernel/rcu/tree_stall.h:1010 rcu_check_gp_start_stall+0x2cf/0x460 kernel/rcu/tree_stall.h:1010
Modules linked in:
CPU: 1 UID: 0 PID: 24 Comm: ksoftirqd/1 Not tainted 6.12.0-rc2-syzkaller-00320-gba01565ced22 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:rcu_check_gp_start_stall+0x2cf/0x460 kernel/rcu/tree_stall.h:1010
Code: c7 c0 1a 41 9a be 04 00 00 00 e8 8c 13 83 00 b8 01 00 00 00 87 05 d1 93 c5 18 85 c0 0f 85 1a ff ff ff 48 c7 c0 00 cc 93 8e 90 <0f> 0b 90 49 39 c7 74 47 48 c7 c0 bc 25 1d 90 48 c1 e8 03 42 0f b6
RSP: 0018:ffffc900001e7a18 EFLAGS: 00010046
RAX: ffffffff8e93cc00 RBX: 00000000ffffee26 RCX: ffffffff817b86e4
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff9a411ac0
RBP: ffffc900001e7c70 R08: 0000000000000003 R09: fffffbfff3482358
R10: dffffc0000000000 R11: fffffbfff3482358 R12: dffffc0000000000
R13: dffffc0000000000 R14: 0000000000000246 R15: ffffffff8e93cc00
FS:  0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7e6a9f7f18 CR3: 0000000027932000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 rcu_core+0x650/0x17a0 kernel/rcu/tree.c:2818
 handle_softirqs+0x2c5/0x980 kernel/softirq.c:554
 run_ksoftirqd+0xca/0x130 kernel/softirq.c:927
 smpboot_thread_fn+0x544/0xa30 kernel/smpboot.c:164
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

Crashes (2742):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/10/14 06:28 upstream ba01565ced22 084d8178 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in rcu_check_gp_start_stall
2024/11/26 16:34 net 5d066766c5f1 11dbc254 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING in rcu_check_gp_start_stall
2024/10/15 02:49 net 0b84db5d8f25 b01b6661 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING in rcu_check_gp_start_stall
2024/02/04 06:52 net b09b58e31b0f a67b2c42 .config console log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING in rcu_check_gp_start_stall
2025/01/13 00:32 net-next 7d0da8f86234 6dbc6a9b .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce WARNING in rcu_check_gp_start_stall
2024/12/05 20:56 net-next da4fa00abe56 6e50d07b .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce WARNING in rcu_check_gp_start_stall
2023/08/30 09:13 net-next bd6c11bc43c4 b42ca3a7 .config console log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce WARNING in rcu_check_gp_start_stall
2023/09/16 19:19 net-next c123e0d30bdb 0b6a67ac .config console log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce WARNING in rcu_check_gp_start_stall
2025/10/31 14:53 upstream d127176862a9 2c50b6a9 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in rcu_check_gp_start_stall
2025/10/22 11:59 upstream 552c50713f27 252fbbad .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in rcu_check_gp_start_stall
2025/10/17 15:40 upstream 98ac9cc4b445 7adf5298 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in rcu_check_gp_start_stall
2025/10/17 13:47 upstream 98ac9cc4b445 7adf5298 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in rcu_check_gp_start_stall
2025/10/12 12:31 upstream 67029a49db6c ff1712fe .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in rcu_check_gp_start_stall
2025/08/23 14:20 upstream 038d61fd6422 bf27483f .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in rcu_check_gp_start_stall
2025/03/03 03:25 upstream 7eb172143d55 c3901742 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in rcu_check_gp_start_stall
2024/12/09 18:07 upstream fac04efc5c79 9ac0fdc6 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in rcu_check_gp_start_stall
2024/05/28 02:49 upstream 2bfcfd584ff5 f550015e .config console log report syz / log [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in rcu_check_gp_start_stall
2024/03/31 09:12 upstream fe46a7dd189e 6baf5069 .config console log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in rcu_check_gp_start_stall
2023/06/02 12:09 upstream 1874a42a7d74 a4ae4f42 .config console log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in rcu_check_gp_start_stall
2024/12/25 16:16 upstream 9b2ffa6148b1 444551c4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 WARNING in rcu_check_gp_start_stall
2025/07/23 04:34 upstream 89be9a83ccf1 e1dd4f22 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in rcu_check_gp_start_stall
2025/09/11 16:10 upstream 7aac71907bde e2beed91 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in rcu_check_gp_start_stall
2025/11/01 23:05 bpf ba36dd5ee6fd 2c50b6a9 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce WARNING in rcu_check_gp_start_stall
2025/10/30 01:13 bpf 2cbb259ec4f8 fd2207e7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce WARNING in rcu_check_gp_start_stall
2025/10/27 17:14 bpf 8ce93aabbf75 fd2207e7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce WARNING in rcu_check_gp_start_stall
2025/10/27 01:05 bpf 8ce93aabbf75 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce WARNING in rcu_check_gp_start_stall
2025/10/24 06:50 bpf 7221b9caf84b c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce WARNING in rcu_check_gp_start_stall
2025/10/24 01:23 bpf 7221b9caf84b c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce WARNING in rcu_check_gp_start_stall
2025/10/22 09:46 bpf 881a9c9cb785 252fbbad .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce WARNING in rcu_check_gp_start_stall
2025/10/21 12:37 bpf 1c64efcb083c 9832ed61 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce WARNING in rcu_check_gp_start_stall
2025/10/20 14:38 bpf 1c64efcb083c 1c8c8cd8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce WARNING in rcu_check_gp_start_stall
2025/10/13 20:58 bpf 3a8660878839 b6605ba8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce WARNING in rcu_check_gp_start_stall
2025/10/13 14:47 bpf 3a8660878839 ff1712fe .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce WARNING in rcu_check_gp_start_stall
2025/10/12 22:43 bpf 67029a49db6c ff1712fe .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce WARNING in rcu_check_gp_start_stall
2025/10/11 05:22 bpf ffce84bccb4d ff1712fe .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce WARNING in rcu_check_gp_start_stall
2025/10/06 01:25 bpf de7342228b73 49379ee0 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce WARNING in rcu_check_gp_start_stall
2025/01/18 12:14 net 70d81f25cc92 f2cb035c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING in rcu_check_gp_start_stall
2024/04/30 22:13 net ba1cb99b559e 9e0e6af1 .config console log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING in rcu_check_gp_start_stall
2024/04/12 02:19 net f99c5f563c17 478efa7f .config console log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING in rcu_check_gp_start_stall
2025/11/05 11:25 bpf-next b3387b312226 a6c9c731 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in rcu_check_gp_start_stall
2025/11/04 12:12 bpf-next e6e10c51fb17 686bf657 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in rcu_check_gp_start_stall
2025/11/04 11:42 bpf-next e6e10c51fb17 686bf657 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in rcu_check_gp_start_stall
2025/11/04 06:34 bpf-next e6e10c51fb17 686bf657 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in rcu_check_gp_start_stall
2025/11/03 07:59 bpf-next ab01bfad61b0 2c50b6a9 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in rcu_check_gp_start_stall
2025/11/02 19:20 bpf-next ab01bfad61b0 2c50b6a9 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in rcu_check_gp_start_stall
2025/11/02 11:04 bpf-next ab01bfad61b0 2c50b6a9 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in rcu_check_gp_start_stall
2025/11/02 08:28 bpf-next ab01bfad61b0 2c50b6a9 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in rcu_check_gp_start_stall
2025/10/30 08:34 bpf-next e2e668bd8106 fd2207e7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in rcu_check_gp_start_stall
2025/10/28 13:02 bpf-next f9db3a38224e fd2207e7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in rcu_check_gp_start_stall
2025/10/28 01:19 bpf-next ff880798de39 fd2207e7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in rcu_check_gp_start_stall
2025/10/24 23:37 bpf-next e7586577b75f c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in rcu_check_gp_start_stall
2025/10/24 08:43 bpf-next e7586577b75f c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in rcu_check_gp_start_stall
2025/10/23 13:57 bpf-next e7586577b75f c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in rcu_check_gp_start_stall
2025/10/21 21:36 bpf-next 04a899573fb8 9832ed61 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in rcu_check_gp_start_stall
2025/10/19 22:00 bpf-next 7361c864852f 1c8c8cd8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in rcu_check_gp_start_stall
2025/10/18 12:02 bpf-next 48a97ffc6c82 1c8c8cd8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in rcu_check_gp_start_stall
2025/10/18 05:37 bpf-next 48a97ffc6c82 1c8c8cd8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in rcu_check_gp_start_stall
2025/10/16 19:35 bpf-next 48a97ffc6c82 19568248 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in rcu_check_gp_start_stall
2025/10/16 13:38 bpf-next 48a97ffc6c82 19568248 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in rcu_check_gp_start_stall
2025/10/15 01:10 bpf-next 39e9d5f63075 b6605ba8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in rcu_check_gp_start_stall
2025/10/14 19:47 bpf-next 39e9d5f63075 b6605ba8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in rcu_check_gp_start_stall
2025/10/11 06:39 bpf-next 2e36338df42d ff1712fe .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in rcu_check_gp_start_stall
2025/10/09 17:07 bpf-next 56b4d162392d 7e2882b3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in rcu_check_gp_start_stall
2025/10/09 07:25 bpf-next 56b4d162392d 7e2882b3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in rcu_check_gp_start_stall
2025/10/09 01:05 bpf-next 56b4d162392d 7e2882b3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in rcu_check_gp_start_stall
2025/10/08 00:46 bpf-next 0db4941d9dae 7e2882b3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in rcu_check_gp_start_stall
2025/10/07 17:43 bpf-next de7342228b73 8ef35d49 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in rcu_check_gp_start_stall
2025/01/22 12:59 net-next b1754a69e7be da72ac06 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce WARNING in rcu_check_gp_start_stall
2025/09/28 17:14 linux-next 262858079afd 001c9061 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in rcu_check_gp_start_stall
2024/04/26 06:01 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing a160e1202ca3 8bdc0f22 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb WARNING in rcu_check_gp_start_stall
2019/02/22 16:31 upstream 8a61716ff2ab 6a5fcca4 .config console log report syz C ci-upstream-kasan-gce-smack-root
2019/02/22 08:04 upstream 8a61716ff2ab 7ff74a98 .config console log report syz C ci-upstream-kasan-gce-root
2020/12/29 06:01 upstream dea8dcf2a9fa 8259d56c .config console log report info ci-qemu-upstream-386
* Struck through repros no longer work on HEAD.