rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5623/1:b..l P4279/1:b..l
(detected by 1, t=10502 jiffies, g=50205, q=19 ncpus=2)
task:syz-executor state:R running task stack:22304 pid:4279 ppid:4261 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x10ec/0x40b0 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_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:696
RIP: 0010:constant_test_bit arch/x86/include/asm/bitops.h:207 [inline]
RIP: 0010:arch_test_bit arch/x86/include/asm/bitops.h:239 [inline]
RIP: 0010:_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:142 [inline]
RIP: 0010:folio_test_swapcache include/linux/page-flags.h:544 [inline]
RIP: 0010:folio_index include/linux/pagemap.h:689 [inline]
RIP: 0010:folio_contains+0x159/0x580 include/linux/pagemap.h:738
Code: 83 e4 01 0f 85 f8 01 00 00 0f 1f 44 00 00 e8 7e 7c d6 ff 48 89 df be 08 00 00 00 e8 51 af 26 00 48 b8 00 00 00 00 00 fc ff df <41> 80 7c 05 00 00 74 08 48 89 df e8 a7 ad 26 00 4c 8b 23 4c 89 e6
RSP: 0018:ffffc900040577a0 EFLAGS: 00000256
RAX: dffffc0000000000 RBX: ffffea0000c3e940 RCX: ffffffff81aa635f
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffea0000c3e940
RBP: 1ffffd4000187d29 R08: dffffc0000000000 R09: fffff94000187d29
R10: fffff94000187d29 R11: 1ffffd4000187d28 R12: 0000000000000000
R13: 1ffffd4000187d28 R14: 0000000000002ae3 R15: ffffea0000c3e948
find_lock_entries+0x5db/0xb90 mm/filemap.c:2134
shmem_undo_range+0x227/0x2050 mm/shmem.c:925
shmem_truncate_range mm/shmem.c:1062 [inline]
shmem_evict_inode+0x248/0xa40 mm/shmem.c:1171
evict+0x485/0x870 fs/inode.c:705
do_unlinkat+0x377/0x560 fs/namei.c:4405
__do_sys_unlink fs/namei.c:4446 [inline]
__se_sys_unlink fs/namei.c:4444 [inline]
__x64_sys_unlink+0x45/0x50 fs/namei.c:4444
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: 0033:0x7fdbb5d8ecf7
RSP: 002b:00007ffc70dc14d8 EFLAGS: 00000206 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fdbb5d8ecf7
RDX: 00007ffc70dc1500 RSI: 00007ffc70dc1590 RDI: 00007ffc70dc1590
RBP: 00007ffc70dc1590 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000100 R11: 0000000000000206 R12: 00007ffc70dc2620
R13: 00007fdbb5e13d7d R14: 0000000000092d83 R15: 00007ffc70dc2660
task:kworker/u4:19 state:R running task stack:20032 pid:5623 ppid:2 flags:0x00004000
Workqueue: bat_events batadv_nc_worker
Call Trace:
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x10ec/0x40b0 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_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:696
RIP: 0010:kasan_check_range+0x1ab/0x290 mm/kasan/generic.c:-1
Code: 4d 89 d6 4d 8d 56 07 4d 85 f6 4d 0f 49 d6 49 83 e2 f8 4d 29 d6 74 12 41 80 39 00 0f 85 a0 00 00 00 49 ff c1 49 ff ce 75 ee 5b <41> 5e 41 5f c3 84 db 75 61 f7 c3 00 ff 00 00 75 5e f7 c3 00 00 ff
RSP: 0018:ffffc90003d9faa8 EFLAGS: 00000256
RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff81630269
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8dff0e28
RBP: ffffc90003d9fbc8 R08: dffffc0000000000 R09: fffffbfff1bfe1c6
R10: fffffbfff1bfe1c6 R11: 1ffffffff1bfe1c5 R12: 0000000000000001
R13: 1ffff920007b3f64 R14: 0000000000000001 R15: dffffc0000000001
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_lock_acquire include/trace/events/lock.h:24 [inline]
lock_acquire+0xd9/0x490 kernel/locking/lockdep.c:5633
rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
rcu_read_lock include/linux/rcupdate.h:791 [inline]
batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline]
batadv_nc_worker+0xeb/0x600 net/batman-adv/network-coding.c:719
process_one_work+0x898/0x1160 kernel/workqueue.c:2292
worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
rcu: rcu_preempt kthread timer wakeup didn't happen for 10562 jiffies! g50205 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: Possible timer handling issue on cpu=1 timer-softirq=31510
rcu: rcu_preempt kthread starved for 10563 jiffies! g50205 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:27200 pid:16 ppid:2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
schedule+0xb9/0x180 kernel/sched/core.c:6637
schedule_timeout+0x15c/0x280 kernel/time/timer.c:2168
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
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 PID: 0 Comm: swapper/1 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:default_idle+0xb/0x10 arch/x86/kernel/process.c:742
Code: 48 89 df e8 a7 b3 b6 f7 e9 4c ff ff ff e8 9d 0e f6 ff 00 00 cc cc 00 00 cc cc 00 00 cc cc 00 66 90 0f 00 2d c7 40 4c 00 fb f4 0f 1f 40 00 41 57 41 56 53 49 be 00 00 00 00 00 fc ff df 65 48
RSP: 0018:ffffc90000177de8 EFLAGS: 000002c6
RAX: 949b2f83b7fdcb00 RBX: ffffffff8a1a6267 RCX: 949b2f83b7fdcb00
RDX: 0000000000000001 RSI: ffffffff8a6c0600 RDI: ffffffff8abef920
RBP: ffffc90000177f20 R08: dffffc0000000000 R09: ffffed10171e6afa
R10: ffffed10171e6afa R11: 1ffff110171e6af9 R12: 0000000000000001
R13: dffffc0000000000 R14: ffff88813fef1dc0 R15: 1ffffffff1bfe206
FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9088fc3e70 CR3: 00000000589e3000 CR4: 00000000003526e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
default_idle_call+0x84/0xc0 kernel/sched/idle.c:109
cpuidle_idle_call kernel/sched/idle.c:191 [inline]
do_idle+0x1fc/0x570 kernel/sched/idle.c:303
cpu_startup_entry+0x3f/0x60 kernel/sched/idle.c:401
start_secondary+0xe4/0xf0 arch/x86/kernel/smpboot.c:281
secondary_startup_64_no_verify+0xcf/0xdb