rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P32756/1:b..l P1857/1:b..l P1867/1:b..l P26096/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=219989, q=488 ncpus=2)
task:kworker/u8:8 state:R running task stack:20136 pid:26096 tgid:26096 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x149b/0x4fd0 kernel/sched/core.c:6863
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7190
irqentry_exit+0x5e3/0x670 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x222/0x340 kernel/locking/lockdep.c:5872
Code: ff ff ff e8 20 d1 bb 09 f7 44 24 08 00 02 00 00 0f 84 3a ff ff ff 65 48 8b 05 0a 20 e2 10 48 3b 44 24 58 75 33 fb 48 83 c4 60 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 da 50 72 ff cc 48 8d 3d 37 78 e7
RSP: 0018:ffffc90003797840 EFLAGS: 00000282
RAX: 8172ba53bf9db300 RBX: 0000000000000000 RCX: 0000000000000046
RDX: 0000000096ff24f8 RSI: ffffffff8d97658e RDI: ffffffff8bc083e0
RBP: ffffffff8b229d40 R08: ffffffff8b229d40 R09: ffffffff8df41aa0
R10: dffffc0000000000 R11: ffffed100a68c817 R12: 0000000000000002
R13: ffffffff8df41aa0 R14: 0000000000000000 R15: 0000000000000246
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:867 [inline]
batadv_iv_ogm_slide_own_bcast_window net/batman-adv/bat_iv_ogm.c:761 [inline]
batadv_iv_ogm_schedule_buff net/batman-adv/bat_iv_ogm.c:833 [inline]
batadv_iv_ogm_schedule+0x454/0xf00 net/batman-adv/bat_iv_ogm.c:873
batadv_iv_send_outstanding_bat_ogm_packet+0x6c6/0x7e0 net/batman-adv/bat_iv_ogm.c:1709
process_one_work kernel/workqueue.c:3257 [inline]
process_scheduled_works+0xad1/0x1770 kernel/workqueue.c:3340
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3421
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
task:syz.7.6977 state:R running task stack:28480 pid:1867 tgid:1866 ppid:492 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x149b/0x4fd0 kernel/sched/core.c:6863
preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:7047
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline]
_raw_spin_unlock+0x3f/0x50 kernel/locking/spinlock.c:186
spin_unlock include/linux/spinlock.h:391 [inline]
insert_pages mm/memory.c:2393 [inline]
vm_insert_pages+0x5db/0x920 mm/memory.c:2433
io_region_mmap io_uring/memmap.c:292 [inline]
io_uring_mmap+0x432/0x540 io_uring/memmap.c:318
vfs_mmap include/linux/fs.h:2053 [inline]
mmap_file mm/internal.h:167 [inline]
__mmap_new_file_vma mm/vma.c:2421 [inline]
__mmap_new_vma mm/vma.c:2484 [inline]
__mmap_region mm/vma.c:2708 [inline]
mmap_region+0x14b1/0x1d10 mm/vma.c:2786
do_mmap+0xc45/0x10d0 mm/mmap.c:558
vm_mmap_pgoff+0x2a6/0x4d0 mm/util.c:581
ksys_mmap_pgoff+0x51f/0x760 mm/mmap.c:604
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f64fcb8f783
RSP: 002b:00007f64fdaa4fc8 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007f64fcde5fa0 RCX: 00007f64fcb8f783
RDX: 0000000000000003 RSI: 0000000000100040 RDI: 0000000000000000
RBP: 00002000000003c0 R08: 0000000000000003 R09: 0000000000000000
R10: 0000000000008001 R11: 0000000000000246 R12: 0000000000000003
R13: 0000000000000000 R14: 0000000000005ffd R15: 0000000000000000
task:syz.3.6973 state:R running task stack:25688 pid:1857 tgid:1855 ppid:28446 task_flags:0x400040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x149b/0x4fd0 kernel/sched/core.c:6863
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7190
irqentry_exit+0x5e3/0x670 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:native_irq_disable arch/x86/include/asm/irqflags.h:37 [inline]
RIP: 0010:arch_local_irq_disable arch/x86/include/asm/irqflags.h:114 [inline]
RIP: 0010:arch_local_irq_save arch/x86/include/asm/irqflags.h:128 [inline]
RIP: 0010:lock_is_held_type+0x4e/0x150 kernel/locking/lockdep.c:5936
Code: 92 26 07 85 c0 0f 85 d6 00 00 00 65 4c 8b 2c 25 08 10 80 92 41 83 bd 2c 0b 00 00 00 0f 85 bf 00 00 00 89 f5 49 89 fe 9c 41 5c 48 c7 c7 a4 6f 7a 8d e8 15 19 00 00 65 ff 05 fe 91 26 07 41 83
RSP: 0000:ffffc9000e11fc08 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 00000000ffffffff RCX: 0000000080000001
RDX: ffff888030835b80 RSI: 00000000ffffffff RDI: ffffffff8df41aa0
RBP: 00000000ffffffff R08: ffff888030835b80 R09: 0000000000000004
R10: 0000000000000003 R11: 0000000000000002 R12: 0000000000000246
R13: ffff888030835b80 R14: ffffffff8df41aa0 R15: ffff888076e40a00
mt_slot lib/maple_tree.c:736 [inline]
mtree_range_walk+0x52a/0x840 lib/maple_tree.c:2579
mas_state_walk lib/maple_tree.c:3298 [inline]
mas_walk+0xc6/0x2e0 lib/maple_tree.c:4599
lock_vma_under_rcu+0x193/0x4a0 mm/mmap_lock.c:253
do_user_addr_fault+0x2d9/0x1380 arch/x86/mm/fault.c:1327
handle_page_fault arch/x86/mm/fault.c:1476 [inline]
exc_page_fault+0x71/0xd0 arch/x86/mm/fault.c:1532
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7fac330509e6
RSP: 002b:00007fac33fb84a0 EFLAGS: 00010206
RAX: 00000000005d0001 RBX: 00007fac33fb8540 RCX: 000000000000004e
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 00007fac33fb85e0
RBP: 0000000000000102 R08: 00007fac28c00000 R09: 00000000005d0000
R10: 0000000000000000 R11: 00007fac33fb8550 R12: 0000000000000001
R13: 00007fac3322fc40 R14: 0000000000000000 R15: 00007fac33fb85e0
task:udevd state:R running task stack:23608 pid:32756 tgid:32756 ppid:5194 task_flags:0x20440140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x149b/0x4fd0 kernel/sched/core.c:6863
preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:7047
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
_raw_spin_unlock_irq+0x45/0x50 kernel/locking/spinlock.c:202
spin_unlock_irq include/linux/spinlock.h:401 [inline]
loop_queue_work drivers/block/loop.c:864 [inline]
loop_queue_rq+0x9f8/0xb00 drivers/block/loop.c:1890
__blk_mq_issue_directly block/blk-mq.c:2715 [inline]
blk_mq_request_issue_directly+0x3c1/0x710 block/blk-mq.c:2802
blk_mq_issue_direct+0x2a0/0x660 block/blk-mq.c:2823
blk_mq_dispatch_queue_requests+0x6fe/0x800 block/blk-mq.c:2898
blk_mq_flush_plug_list+0x432/0x550 block/blk-mq.c:2981
__blk_flush_plug+0x3d3/0x4b0 block/blk-core.c:1225
blk_finish_plug+0x5e/0x90 block/blk-core.c:1252
read_pages+0x3b2/0x580 mm/readahead.c:176
page_cache_ra_unbounded+0x750/0x990 mm/readahead.c:302
do_page_cache_ra mm/readahead.c:332 [inline]
force_page_cache_ra mm/readahead.c:361 [inline]
page_cache_sync_ra+0x433/0xc40 mm/readahead.c:579
filemap_get_pages+0x468/0x1dc0 mm/filemap.c:2690
filemap_read+0x3f6/0x11a0 mm/filemap.c:2800
blkdev_read_iter+0x30a/0x440 block/fops.c:856
new_sync_read fs/read_write.c:491 [inline]
vfs_read+0x55a/0xa30 fs/read_write.c:572
ksys_read+0x145/0x250 fs/read_write.c:715
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f88fc2a7407
RSP: 002b:00007ffd68343950 EFLAGS: 00000202 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007f88fca76880 RCX: 00007f88fc2a7407
RDX: 0000000000000600 RSI: 00007f88fca73000 RDI: 0000000000000009
RBP: 000055c8df000050 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 0000000000040000 R14: 000055c8df0038b8 R15: 00007f88fcb9d39c
rcu: rcu_preempt kthread starved for 10628 jiffies! g219989 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:26656 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x149b/0x4fd0 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6960
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+0x510/0xa50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: 1e 84 b6 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 53 91 0e 00 f3 0f 1e fa fb f4 f3 83 b6 f5 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90000197e20 EFLAGS: 000002c6
RAX: 00000000087b8937 RBX: ffffffff819713ee RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8d79263f RDI: ffffffff8bc083e0
RBP: ffffc90000197f10 R08: ffff8880b87336db R09: 1ffff110170e66db
R10: dffffc0000000000 R11: ffffed10170e66dc R12: ffffffff8f822370
R13: 1ffff110038d4b70 R14: 0000000000000001 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff888125f1f000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055556204d808 CR3: 000000000dd3a000 CR4: 0000000000350ef0
Call Trace:
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:767
default_idle_call+0x73/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:191 [inline]
do_idle+0x1be/0x4d0 kernel/sched/idle.c:332
cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:430
start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:312
common_startup_64+0x13e/0x147