rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P14936/1:b..l P72/1:b..l P10202/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=72249, q=641 ncpus=2)
task:kworker/u8:18 state:R running task stack:21768 pid:10202 tgid:10202 ppid:2 task_flags:0x4208060 flags:0x00004000
Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7288
irqentry_exit+0x6f/0x90 kernel/entry/common.c:197
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:__kasan_check_byte+0x14/0x40 mm/kasan/common.c:567
Code: ff ff 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 0f 1f 00 41 56 53 48 89 f3 49 89 fe e8 5e 14 00 00 84 c0 <75> 16 be 01 00 00 00 4c 89 f7 31 d2 48 89 d9 89 c3 e8 c6 03 00 00
RSP: 0018:ffffc900141577c8 EFLAGS: 00000202
RAX: 0000000000000001 RBX: ffffffff8b42c644 RCX: aa92f93fd2ac4c00
RDX: 0000000000000000 RSI: ffffffff8b42c644 RDI: 1ffffffff1c2741c
RBP: ffffffff8b42c620 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed100a65ac17 R12: 0000000000000002
R13: ffffffff8e13a0e0 R14: ffffffff8e13a0e0 R15: 0000000000000000
kasan_check_byte include/linux/kasan.h:399 [inline]
lock_acquire+0x8d/0x360 kernel/locking/lockdep.c:5842
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:841 [inline]
batadv_iv_ogm_slide_own_bcast_window net/batman-adv/bat_iv_ogm.c:762 [inline]
batadv_iv_ogm_schedule_buff net/batman-adv/bat_iv_ogm.c:834 [inline]
batadv_iv_ogm_schedule+0x454/0xf00 net/batman-adv/bat_iv_ogm.c:874
batadv_iv_send_outstanding_bat_ogm_packet+0x6c6/0x7e0 net/batman-adv/bat_iv_ogm.c:1714
process_one_work kernel/workqueue.c:3236 [inline]
process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3319
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x439/0x7d0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
task:kworker/u8:5 state:R running task stack:21192 pid:72 tgid:72 ppid:2 task_flags:0x24208060 flags:0x00004000
Workqueue: writeback wb_workfn (flush-8:0)
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:7145
preempt_schedule+0xae/0xc0 kernel/sched/core.c:7169
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
rcu_read_unlock_sched include/linux/rcupdate.h:955 [inline]
pfn_valid include/linux/mmzone.h:2172 [inline]
bvec_phys+0x4f7/0x570 include/linux/bvec.h:298
blk_map_iter_next+0x1d5/0xe70 block/blk-mq-dma.c:32
__blk_rq_map_sg+0xba/0x470 block/blk-mq-dma.c:259
scsi_alloc_sgtables+0x2ec/0xc40 drivers/scsi/scsi_lib.c:1151
sd_setup_read_write_cmnd drivers/scsi/sd.c:1336 [inline]
sd_init_command+0x558/0x1ff0 drivers/scsi/sd.c:1458
scsi_prepare_cmd drivers/scsi/scsi_lib.c:1708 [inline]
scsi_queue_rq+0x1771/0x2cc0 drivers/scsi/scsi_lib.c:1849
blk_mq_dispatch_rq_list+0x4c0/0x1900 block/blk-mq.c:2120
__blk_mq_do_dispatch_sched block/blk-mq-sched.c:168 [inline]
blk_mq_do_dispatch_sched block/blk-mq-sched.c:182 [inline]
__blk_mq_sched_dispatch_requests+0xda4/0x1570 block/blk-mq-sched.c:307
blk_mq_sched_dispatch_requests+0xd7/0x190 block/blk-mq-sched.c:329
blk_mq_run_hw_queue+0x404/0x4f0 block/blk-mq.c:2358
blk_mq_dispatch_list+0xd0c/0xe00 include/linux/spinlock.h:-1
blk_mq_flush_plug_list+0x469/0x550 block/blk-mq.c:2967
__blk_flush_plug+0x3d3/0x4b0 block/blk-core.c:1220
blk_finish_plug+0x5e/0x90 block/blk-core.c:1247
wb_writeback+0xa80/0xaf0 fs/fs-writeback.c:2194
wb_check_old_data_flush fs/fs-writeback.c:2262 [inline]
wb_do_writeback fs/fs-writeback.c:2315 [inline]
wb_workfn+0xaef/0xef0 fs/fs-writeback.c:2343
process_one_work kernel/workqueue.c:3236 [inline]
process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3319
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x439/0x7d0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
task:syz.9.2108 state:R running task stack:25096 pid:14936 tgid:14936 ppid:13069 task_flags:0x400040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7288
irqentry_exit+0x6f/0x90 kernel/entry/common.c:197
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_acquire+0x175/0x360 kernel/locking/lockdep.c:5872
Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 7b 71 03 11 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc9000bb0fe08 EFLAGS: 00000206
RAX: c67da242f687a900 RBX: 0000000000000000 RCX: c67da242f687a900
RDX: 0000000000000001 RSI: ffffffff8dba996e RDI: ffffffff8be33f80
RBP: ffffffff818c55e8 R08: 0000000000000000 R09: ffffffff818c55e8
R10: dffffc0000000000 R11: fffffbfff1f474e7 R12: 0000000000000002
R13: ffffffff8e13a0e0 R14: 0000000000000000 R15: 0000000000000246
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:841 [inline]
__task_pid_nr_ns+0x48/0x470 kernel/pid.c:514
task_tgid_vnr include/linux/pid.h:298 [inline]
__ia32_sys_getpid+0x1e/0x30 kernel/sys.c:1001
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fccaf785d67
RSP: 002b:00007fff8a6fac08 EFLAGS: 00000202 ORIG_RAX: 0000000000000027
RAX: ffffffffffffffda RBX: 00007fff8a6fad70 RCX: 00007fccaf785d67
RDX: 00007fff8a6fac40 RSI: 00007fff8a6fad70 RDI: 0000000000000021
RBP: 0000000000000001 R08: 00007fccaf9d0000 R09: 00007fccaf9d2000
R10: 000000008168b466 R11: 0000000000000202 R12: 0000000000000014
R13: 0000000000000000 R14: ffffffff8168b282 R15: 0000000000004481
rcu: rcu_preempt kthread starved for 10504 jiffies! g72249 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R running task stack:26800 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7058
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083
rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x439/0x7d0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full)
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:82
Code: 3e ed 95 f5 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d b3 d9 0d 00 f3 0f 1e fa fb f4 13 ed 95 f5 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffffff8de07d80 EFLAGS: 000002c2
RAX: 2b8c9e19870b1300 RBX: ffffffff819683f8 RCX: 2b8c9e19870b1300
RDX: 0000000000000001 RSI: ffffffff8d9ba307 RDI: ffffffff8be33f80
RBP: ffffffff8de07eb8 R08: ffff8880b8632f9b R09: 1ffff110170c65f3
R10: dffffc0000000000 R11: ffffed10170c65f4 R12: ffffffff8fa3a730
R13: 0000000000000000 R14: 0000000000000000 R15: 1ffffffff1bd2a20
FS: 0000000000000000(0000) GS:ffff888125c13000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4762804614 CR3: 000000007ccf3000 CR4: 0000000000350ef0
Call Trace:
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:757
default_idle_call+0x74/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:190 [inline]
do_idle+0x1e8/0x510 kernel/sched/idle.c:330
cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:428
rest_init+0x2de/0x300 init/main.c:744
start_kernel+0x3a9/0x410 init/main.c:1097
x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:307
x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:288
common_startup_64+0x13e/0x147