[v6.1] INFO: rcu detected stall in sys_execve

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 75cefdf153f5 Linux 6.1.127
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=13bc0e18580000
kernel config: https://syzkaller.appspot.com/x/.config?x=3dc848f1f9c50685
dashboard link: https://syzkaller.appspot.com/bug?extid=c8f053523131494fd85d
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/9fa70d9fd10a/disk-75cefdf1.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/d01cb9bb9789/vmlinux-75cefdf1.xz
kernel image: https://storage.googleapis.com/syzbot-assets/487423b91d50/bzImage-75cefdf1.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c8f053...@syzkaller.appspotmail.com

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-...!: (0 ticks this GP) idle=fdc4/1/0x4000000000000000 softirq=25907/25907 fqs=0
(detected by 1, t=10505 jiffies, g=36121, q=11 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 8013 Comm: dhcpcd-run-hook Not tainted 6.1.127-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
RIP: 0010:lock_acquire+0x6/0x5a0 kernel/locking/lockdep.c:5630
Code: c7 f8 5b 9b 8e e8 5a 8e 77 00 e9 a2 fd ff ff 0f 1f 44 00 00 65 8b 05 11 ce 97 7e a9 00 ff ff 00 0f 95 c0 c3 55 48 89 e5 41 57 <41> 56 41 55 41 54 53 48 83 e4 e0 48 81 ec 20 01 00 00 4c 89 4c 24
RSP: 0018:ffffc90000007c00 EFLAGS: 00000046
RAX: 0000000000010003 RBX: 1ffff92000000f88 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff975ba258
RBP: ffffc90000007c08 R08: 0000000000000001 R09: 0000000000000000
R10: ffffffffffffffff R11: dffffc0000000001 R12: 0000000000000046
R13: 1ffff92000000f84 R14: ffffffff975ba240 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2d61eff8 CR3: 000000002accd000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<NMI>
</NMI>
<IRQ>
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162
debug_object_activate+0x68/0x4e0 lib/debugobjects.c:698
debug_hrtimer_activate kernel/time/hrtimer.c:421 [inline]
debug_activate kernel/time/hrtimer.c:476 [inline]
enqueue_hrtimer+0x30/0x410 kernel/time/hrtimer.c:1085
__run_hrtimer kernel/time/hrtimer.c:1706 [inline]
__hrtimer_run_queues+0x728/0xe50 kernel/time/hrtimer.c:1753
hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1815
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline]
__sysvec_apic_timer_interrupt+0x158/0x5b0 arch/x86/kernel/apic/apic.c:1124
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1118
</IRQ>
<TASK>
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xd4/0x130 kernel/locking/spinlock.c:194
Code: 9c 8f 44 24 20 42 80 3c 23 00 74 08 4c 89 f7 e8 02 f0 24 f7 f6 44 24 21 02 75 4e 41 f7 c7 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> f7 4f a1 f6 65 8b 05 98 2f 45 75 85 c0 74 3f 48 c7 04 24 0e 36
RSP: 0018:ffffc9000540f5a0 EFLAGS: 00000206
RAX: 4841af421361dd00 RBX: 1ffff92000a81eb8 RCX: ffffffff816b127a
RDX: dffffc0000000000 RSI: ffffffff8b0c0340 RDI: 0000000000000001
RBP: ffffc9000540f638 R08: dffffc0000000000 R09: fffffbfff224a053
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: 1ffff92000a81eb4 R14: ffffc9000540f5c0 R15: 0000000000000246
__debug_check_no_obj_freed lib/debugobjects.c:988 [inline]
debug_check_no_obj_freed+0x455/0x4e0 lib/debugobjects.c:1009
slab_free_hook mm/slub.c:1699 [inline]
slab_free_freelist_hook mm/slub.c:1750 [inline]
slab_free mm/slub.c:3661 [inline]
kmem_cache_free+0x241/0x510 mm/slub.c:3683
remove_vma mm/mmap.c:143 [inline]
exit_mmap+0x4cf/0x980 mm/mmap.c:3260
__mmput+0x115/0x3c0 kernel/fork.c:1200
exec_mmap+0x4fa/0x5b0 fs/exec.c:1040
begin_new_exec+0xaf9/0x1dd0 fs/exec.c:1299
load_elf_binary+0x955/0x2720 fs/binfmt_elf.c:1002
search_binary_handler fs/exec.c:1741 [inline]
exec_binprm fs/exec.c:1782 [inline]
bprm_execve+0x96a/0x18a0 fs/exec.c:1851
do_execveat_common+0x580/0x720 fs/exec.c:1956
do_execve fs/exec.c:2030 [inline]
__do_sys_execve fs/exec.c:2106 [inline]
__se_sys_execve fs/exec.c:2101 [inline]
__x64_sys_execve+0x8e/0xa0 fs/exec.c:2101
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f36e10f7ef7
Code: Unable to access opcode bytes at 0x7f36e10f7ecd.
RSP: 002b:00007ffe8db63998 EFLAGS: 00000246 ORIG_RAX: 000000000000003b
RAX: ffffffffffffffda RBX: 000055912fa51020 RCX: 00007f36e10f7ef7
RDX: 000055912fa51048 RSI: 000055912fa51020 RDI: 000055912fa510d0
RBP: 000055912fa510d0 R08: 000055912fa510d9 R09: 00007ffe8db66ec6
R10: 0000000000000008 R11: 0000000000000246 R12: 000055912fa51048
R13: 00007f36e12a5904 R14: 000055912fa51048 R15: 0000000000000000
</TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10504 jiffies! g36121 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: Possible timer handling issue on cpu=0 timer-softirq=19015
rcu: rcu_preempt kthread starved for 10505 jiffies! g36121 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:26040 pid:16 ppid:2 flags:0x00004000
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5241 [inline]
__schedule+0x143f/0x4570 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+0x2d2/0x1150 kernel/rcu/tree.c:1706
rcu_gp_kthread+0xa3/0x3b0 kernel/rcu/tree.c:1905
kthread+0x28d/0x320 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:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 8013 Comm: dhcpcd-run-hook Not tainted 6.1.127-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
RIP: 0010:variable_test_bit arch/x86/include/asm/bitops.h:228 [inline]
RIP: 0010:arch_test_bit arch/x86/include/asm/bitops.h:240 [inline]
RIP: 0010:_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:142 [inline]
RIP: 0010:hlock_class kernel/locking/lockdep.c:228 [inline]
RIP: 0010:lookup_chain_cache_add kernel/locking/lockdep.c:3737 [inline]
RIP: 0010:validate_chain+0x112/0x5950 kernel/locking/lockdep.c:3793
Code: 3d 00 00 04 00 0f 85 98 04 00 00 81 e3 ff 1f 00 00 48 89 d8 48 c1 e8 06 48 8d 3c c5 60 02 25 91 be 08 00 00 00 e8 6e d2 76 00 <48> 0f a3 1d a6 a3 b9 0f 72 25 48 c7 c0 60 71 35 97 48 c1 e8 03 42
RSP: 0018:ffffc90000007740 EFLAGS: 00000056
RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff816b5eb2
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff91250260
RBP: ffffc900000079f0 R08: dffffc0000000000 R09: fffffbfff224a04d
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: ffff8880276164e0 R14: cf82e703b144b952 R15: 1ffff11004ec2c9c
FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2d61eff8 CR3: 000000002accd000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<NMI>
</NMI>
<IRQ>
__lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5049
lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162
debug_object_deactivate+0x63/0x380 lib/debugobjects.c:753
debug_hrtimer_deactivate kernel/time/hrtimer.c:426 [inline]
debug_deactivate+0x1d/0x280 kernel/time/hrtimer.c:482
__run_hrtimer kernel/time/hrtimer.c:1657 [inline]
__hrtimer_run_queues+0x334/0xe50 kernel/time/hrtimer.c:1753
hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1815
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline]
__sysvec_apic_timer_interrupt+0x158/0x5b0 arch/x86/kernel/apic/apic.c:1124
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1118
</IRQ>
<TASK>
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xd4/0x130 kernel/locking/spinlock.c:194
Code: 9c 8f 44 24 20 42 80 3c 23 00 74 08 4c 89 f7 e8 02 f0 24 f7 f6 44 24 21 02 75 4e 41 f7 c7 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> f7 4f a1 f6 65 8b 05 98 2f 45 75 85 c0 74 3f 48 c7 04 24 0e 36
RSP: 0018:ffffc9000540f5a0 EFLAGS: 00000206
RAX: 4841af421361dd00 RBX: 1ffff92000a81eb8 RCX: ffffffff816b127a
RDX: dffffc0000000000 RSI: ffffffff8b0c0340 RDI: 0000000000000001
RBP: ffffc9000540f638 R08: dffffc0000000000 R09: fffffbfff224a053
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: 1ffff92000a81eb4 R14: ffffc9000540f5c0 R15: 0000000000000246
__debug_check_no_obj_freed lib/debugobjects.c:988 [inline]
debug_check_no_obj_freed+0x455/0x4e0 lib/debugobjects.c:1009
slab_free_hook mm/slub.c:1699 [inline]
slab_free_freelist_hook mm/slub.c:1750 [inline]
slab_free mm/slub.c:3661 [inline]
kmem_cache_free+0x241/0x510 mm/slub.c:3683
remove_vma mm/mmap.c:143 [inline]
exit_mmap+0x4cf/0x980 mm/mmap.c:3260
__mmput+0x115/0x3c0 kernel/fork.c:1200
exec_mmap+0x4fa/0x5b0 fs/exec.c:1040
begin_new_exec+0xaf9/0x1dd0 fs/exec.c:1299
load_elf_binary+0x955/0x2720 fs/binfmt_elf.c:1002
search_binary_handler fs/exec.c:1741 [inline]
exec_binprm fs/exec.c:1782 [inline]
bprm_execve+0x96a/0x18a0 fs/exec.c:1851
do_execveat_common+0x580/0x720 fs/exec.c:1956
do_execve fs/exec.c:2030 [inline]
__do_sys_execve fs/exec.c:2106 [inline]
__se_sys_execve fs/exec.c:2101 [inline]
__x64_sys_execve+0x8e/0xa0 fs/exec.c:2101
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f36e10f7ef7
Code: Unable to access opcode bytes at 0x7f36e10f7ecd.
RSP: 002b:00007ffe8db63998 EFLAGS: 00000246 ORIG_RAX: 000000000000003b
RAX: ffffffffffffffda RBX: 000055912fa51020 RCX: 00007f36e10f7ef7
RDX: 000055912fa51048 RSI: 000055912fa51020 RDI: 000055912fa510d0
RBP: 000055912fa510d0 R08: 000055912fa510d9 R09: 00007ffe8db66ec6
R10: 0000000000000008 R11: 0000000000000246 R12: 000055912fa51048
R13: 00007f36e12a5904 R14: 000055912fa51048 R15: 0000000000000000
</TASK>


---
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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 147338df3487 Linux 6.6.108
git tree: linux-6.6.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1683505b980000
kernel config: https://syzkaller.appspot.com/x/.config?x=12606d4b8832c7e4
dashboard link: https://syzkaller.appspot.com/bug?extid=8920db091008b77f7576
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:

disk image: https://storage.googleapis.com/syzbot-assets/23d0a7436789/disk-147338df.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/5658c8bd0cce/vmlinux-147338df.xz
kernel image: https://storage.googleapis.com/syzbot-assets/be243abccdbe/bzImage-147338df.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:

Reported-by: syzbot+8920db...@syzkaller.appspotmail.com

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:

rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P1327/1:b..l P8140/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=29305, q=378 ncpus=2)
task:dhcpcd-run-hook state:R running task stack:27472 pid:8140 ppid:8137 flags:0x00004002
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5380 [inline]
__schedule+0x14d2/0x44d0 kernel/sched/core.c:6699
preempt_schedule_irq+0xb5/0x140 kernel/sched/core.c:7009
irqentry_exit+0x67/0x70 kernel/entry/common.c:438
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:lock_is_held_type+0x13e/0x190 kernel/locking/lockdep.c:5830
Code: 75 40 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 75 46 41 f7 c5 00 02 00 00 74 01 fb 65 48 8b 04 25 28 00 00 00 <48> 3b 44 24 08 75 3c 89 e8 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f
RSP: 0018:ffffc900038d7618 EFLAGS: 00000206
RAX: e9698132302adb00 RBX: ffff888024153c00 RCX: e9698132302adb00
RDX: 0000000000000000 RSI: ffffffff8aaace20 RDI: ffffffff8afc71c0
RBP: 0000000000000001 R08: dffffc0000000000 R09: 1ffffffff21b4ca0
R10: dffffc0000000000 R11: fffffbfff21b4ca1 R12: 0000000000000003
R13: 0000000000000246 R14: ffffffff8cd2fe20 R15: ffff888024154758
lookup_page_ext mm/page_ext.c:240 [inline]
page_ext_get+0x193/0x2b0 mm/page_ext.c:509
__reset_page_owner+0x2e/0x190 mm/page_owner.c:145
reset_page_owner include/linux/page_owner.h:24 [inline]
free_pages_prepare mm/page_alloc.c:1154 [inline]
free_unref_page_prepare+0x7ce/0x8e0 mm/page_alloc.c:2336
free_unref_page+0x32/0x2e0 mm/page_alloc.c:2429
discard_slab mm/slub.c:2127 [inline]
__unfreeze_partials+0x1cf/0x210 mm/slub.c:2667
put_cpu_partial+0x17c/0x250 mm/slub.c:2743
__slab_free+0x31d/0x410 mm/slub.c:3700
qlink_free mm/kasan/quarantine.c:166 [inline]
qlist_free_all+0x75/0xe0 mm/kasan/quarantine.c:185
kasan_quarantine_reduce+0x143/0x160 mm/kasan/quarantine.c:292
__kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:305
kasan_slab_alloc include/linux/kasan.h:188 [inline]
slab_post_alloc_hook+0x6e/0x4d0 mm/slab.h:767
slab_alloc_node mm/slub.c:3495 [inline]
__kmem_cache_alloc_node+0x13e/0x260 mm/slub.c:3534
__do_kmalloc_node mm/slab_common.c:1006 [inline]
__kmalloc+0xa4/0x240 mm/slab_common.c:1020
kmalloc include/linux/slab.h:604 [inline]
tomoyo_realpath_from_path+0xe3/0x5d0 security/tomoyo/realpath.c:251
tomoyo_realpath_nofollow+0xbc/0x100 security/tomoyo/realpath.c:304
tomoyo_find_next_domain+0x253/0x1a60 security/tomoyo/domain.c:726
tomoyo_bprm_check_security+0x116/0x170 security/tomoyo/tomoyo.c:101
security_bprm_check+0x62/0xa0 security/security.c:1103
search_binary_handler fs/exec.c:1763 [inline]
exec_binprm fs/exec.c:1817 [inline]
bprm_execve+0xa51/0x16f0 fs/exec.c:1892
do_execveat_common+0x51b/0x6c0 fs/exec.c:1998
do_execve fs/exec.c:2072 [inline]
__do_sys_execve fs/exec.c:2148 [inline]
__se_sys_execve fs/exec.c:2143 [inline]
__x64_sys_execve+0x92/0xa0 fs/exec.c:2143
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fc944c4a107
RSP: 002b:00007ffc6bdac408 EFLAGS: 00000246 ORIG_RAX: 000000000000003b
RAX: ffffffffffffffda RBX: 000055ecd117d078 RCX: 00007fc944c4a107
RDX: 000055ecd117d0a0 RSI: 000055ecd117d078 RDI: 000055ecd117d130
RBP: 000055ecd117d130 R08: 00007ffc6bdb1e6d R09: 0000000000000000
R10: 0000000000000008 R11: 0000000000000246 R12: 000055ecd117d0a0
R13: 00007fc944e0fe8b R14: 000055ecd117d0a0 R15: 0000000000000000
</TASK>
task:kworker/u4:7 state:R running task stack:22728 pid:1327 ppid:2 flags:0x00004000
Workqueue: bat_events batadv_nc_worker
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5380 [inline]
__schedule+0x14d2/0x44d0 kernel/sched/core.c:6699
preempt_schedule_irq+0xb5/0x140 kernel/sched/core.c:7009
irqentry_exit+0x67/0x70 kernel/entry/common.c:438
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:lock_acquire+0x1f2/0x410 kernel/locking/lockdep.c:5758
Code: 00 9c 8f 84 24 80 00 00 00 f6 84 24 81 00 00 00 02 0f 85 f5 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 04 3c 00 00 00 00 66 43 c7 44 3c 09 00 00 43 c6 44 3c 0b 00
RSP: 0018:ffffc90004b17a40 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 978b318831f68800
RDX: 0000000000000000 RSI: ffffffff8aaace20 RDI: ffffffff8afc71c0
RBP: ffffc90004b17b48 R08: dffffc0000000000 R09: 1ffffffff21b4ca0
R10: dffffc0000000000 R11: fffffbfff21b4ca1 R12: 1ffff92000962f54
R13: ffffffff8cd2fe20 R14: 0000000000000246 R15: dffffc0000000000
rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
rcu_read_lock include/linux/rcupdate.h:786 [inline]
batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline]
batadv_nc_worker+0xef/0x610 net/batman-adv/network-coding.c:719
process_one_work kernel/workqueue.c:2634 [inline]
process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
</TASK>
rcu: rcu_preempt kthread starved for 10378 jiffies! g29305 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:26568 pid:17 ppid:2 flags:0x00004000
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5380 [inline]
__schedule+0x14d2/0x44d0 kernel/sched/core.c:6699
schedule+0xbd/0x170 kernel/sched/core.c:6773
schedule_timeout+0x160/0x280 kernel/time/timer.c:2167
rcu_gp_fqs_loop+0x302/0x1560 kernel/rcu/tree.c:1667
rcu_gp_kthread+0x99/0x380 kernel/rcu/tree.c:1866
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293

</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: 0 Comm: swapper/1 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:148
Code: cc cc cc cc cc cc cc f3 0f 1e fa 0f 0b 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 66 90 0f 00 2d a3 e8 39 00 f3 0f 1e fa fb f4 <c3> cc cc cc cc cc cc cc cc cc cc cc cc 66 0f 1f 00 55 41 57 41 56
RSP: 0018:ffffc90000187de0 EFLAGS: 000002c2
RAX: b30bf8424d263400 RBX: ffffffff8161925b RCX: b30bf8424d263400
RDX: 0000000000000001 RSI: ffffffff8aaabca0 RDI: ffffffff8afc71c0
RBP: ffffc90000187f20 R08: ffff8880b8f36b2b R09: 1ffff110171e6d65
R10: dffffc0000000000 R11: ffffed10171e6d66 R12: ffffffff8e4a7fe8
R13: 0000000000000001 R14: 0000000000000001 R15: 1ffff110037cd780
FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000

CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 00007f403b413db9 CR3: 000000007de54000 CR4: 00000000003506e0
Call Trace:
<TASK>
arch_safe_halt arch/x86/include/asm/paravirt.h:108 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:753
default_idle_call+0x6c/0xa0 kernel/sched/idle.c:97
cpuidle_idle_call kernel/sched/idle.c:170 [inline]
do_idle+0x1eb/0x510 kernel/sched/idle.c:282
cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:380
start_secondary+0xee/0xf0 arch/x86/kernel/smpboot.c:323
secondary_startup_64_no_verify+0x179/0x17b