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INFO: rcu detected stall in call_usermodehelper_exec_async (2)

Status: upstream: reported on 2025/06/23 17:46
Reported-by: syzbot+765f575d185d7060da41@syzkaller.appspotmail.com
First crash: 22d, last: 22d
▶ ▼ Similar bugs (6)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 INFO: rcu detected stall in call_usermodehelper_exec_async 1 1 403d 403d 0/3 auto-obsoleted due to no activity on 2024/09/16 03:00
upstream INFO: rcu detected stall in call_usermodehelper_exec_async kernel 1 1 2052d 2052d 0/29 closed as invalid on 2019/12/04 14:14
linux-5.15 INFO: rcu detected stall in call_usermodehelper_exec_async 1 1 745d 745d 0/3 auto-obsoleted due to no activity on 2023/10/09 16:55
upstream INFO: rcu detected stall in call_usermodehelper_exec_async (3) mm 1 23 152d 649d 0/29 auto-obsoleted due to no activity on 2025/05/14 21:52
upstream INFO: rcu detected stall in call_usermodehelper_exec_async (2) cgroups mm 1 1 1142d 1142d 0/29 auto-closed as invalid on 2022/08/28 20:38
upstream BUG: soft lockup in call_usermodehelper_exec_async mm 1 2 1348d 1398d 0/29 closed as dup on 2021/09/17 07:37

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P3623/1:b..l P4983/1:b..l
	(detected by 0, t=10502 jiffies, g=12961, q=114 ncpus=2)
task:modprobe        state:R  running task     stack:25456 pid:4983  ppid:4407   flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10e9/0x40d0 kernel/sched/core.c:6561
 preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6873
 irqentry_exit+0x63/0x70 kernel/entry/common.c:439
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:__sanitizer_cov_trace_cmp8+0x7a/0x80 kernel/kcov.c:294
Code: c1 e1 05 4c 8d 51 28 4d 39 ca 77 1e 49 ff c0 4c 89 02 48 c7 44 0a 08 06 00 00 00 48 89 7c 0a 10 48 89 74 0a 18 48 89 44 0a 20 <c3> 0f 1f 44 00 00 48 8b 04 24 65 48 8b 15 64 96 81 7e 65 8b 0d 65
RSP: 0018:ffffc900039a7738 EFLAGS: 00000293
RAX: ffffffff89fd6d26 RBX: dffffc0000000000 RCX: ffff888054d59dc0
RDX: 0000000000000000 RSI: ffff88801746f800 RDI: ffff88807bcd4a00
RBP: ffffc900039a7910 R08: ffff888054d59dc0 R09: 0000000000000003
R10: 0000000000000003 R11: 0000000000000000 R12: ffff88801746f800
R13: ffff88807bcd4a80 R14: ffff88807bcd4a00 R15: 0000000000000001
 ma_dead_node lib/maple_tree.c:537 [inline]
 mas_data_end lib/maple_tree.c:1487 [inline]
 mt_validate_nulls lib/maple_tree.c:7195 [inline]
 mt_validate+0x4516/0x4c90 lib/maple_tree.c:7244
 validate_mm_mt+0xcd/0x420 mm/mmap.c:294
 __install_special_mapping+0x2f/0x2f0 mm/mmap.c:3538
 map_vdso+0x161/0x2e0 arch/x86/entry/vdso/vma.c:268
 load_elf_binary+0x1c2e/0x26d0 fs/binfmt_elf.c:1309
 search_binary_handler fs/exec.c:1764 [inline]
 exec_binprm fs/exec.c:1805 [inline]
 bprm_execve+0xb10/0x18a0 fs/exec.c:1874
 kernel_execve+0x8b9/0x9c0 fs/exec.c:2039
 call_usermodehelper_exec_async+0x207/0x350 kernel/umh.c:113
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
task:udevd           state:R  running task     stack:23040 pid:3623  ppid:1      flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10e9/0x40d0 kernel/sched/core.c:6561
 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:6730
 preempt_schedule+0xa7/0xb0 kernel/sched/core.c:6754
 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
 _raw_spin_unlock_irqrestore+0xf6/0x100 kernel/locking/spinlock.c:194
 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
 __wake_up_common_lock kernel/sched/wait.c:140 [inline]
 __wake_up_sync_key+0x11b/0x180 kernel/sched/wait.c:208
 sock_def_readable+0x15b/0x280 net/core/sock.c:3308
 __netlink_sendskb net/netlink/af_netlink.c:1258 [inline]
 netlink_sendskb+0x97/0x130 net/netlink/af_netlink.c:1264
 netlink_sendmsg+0x89e/0xbc0 net/netlink/af_netlink.c:1859
 sock_sendmsg_nosec net/socket.c:718 [inline]
 __sock_sendmsg net/socket.c:730 [inline]
 ____sys_sendmsg+0x59b/0x970 net/socket.c:2519
 ___sys_sendmsg+0x21c/0x290 net/socket.c:2573
 __sys_sendmsg net/socket.c:2602 [inline]
 __do_sys_sendmsg net/socket.c:2611 [inline]
 __se_sys_sendmsg+0x19e/0x270 net/socket.c:2609
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f5f538a7407
RSP: 002b:00007ffcd96bcbd0 EFLAGS: 00000202 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f5f54027880 RCX: 00007f5f538a7407
RDX: 0000000000000000 RSI: 00007ffcd96bcc30 RDI: 0000000000000004
RBP: 000056045f7cc250 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000072
R13: 000056045f7329e0 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10556 jiffies! g12961 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=5033
rcu: rcu_preempt kthread starved for 10557 jiffies! g12961 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0
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:27464 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10e9/0x40d0 kernel/sched/core.c:6561
 schedule+0xb9/0x180 kernel/sched/core.c:6637
 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1965
 rcu_gp_fqs_loop+0x2f2/0x1310 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0x95/0x380 kernel/rcu/tree.c:1905
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 PID: 4943 Comm: syz.1.138 Not tainted 6.1.141-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0033:0x7ff4037b7060
Code: 83 c0 16 83 e0 f7 74 12 50 48 8d 3d ca 27 08 00 e8 15 90 f8 ff 0f 1f 44 00 00 c3 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 <83> ff 21 74 0b c3 66 2e 0f 1f 84 00 00 00 00 00 55 53 48 89 f3 48
RSP: 002b:00007ff4045deb38 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 00007ff4039b5fa8 RCX: 00007ff40378e929
RDX: 00007ff4045deb40 RSI: 00007ff4045dec70 RDI: 0000000000000021
RBP: 00007ff4039b5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ff4039b5fac
R13: 0000000000000000 R14: 00007ffe5cc6fea0 R15: 00007ffe5cc6ff88
FS:  00007ff4045df6c0 GS:  0000000000000000
sched: RT throttling activated

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/06/23 17:45 linux-6.1.y 58485ff1a74f d6cdfb8a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in call_usermodehelper_exec_async
* Struck through repros no longer work on HEAD.