rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P16357/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=105673, q=117 ncpus=2)
task:syz.0.2645 state:R running task stack:25912 pid:16357 tgid:16353 ppid:10219 task_flags:0x400040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5387 [inline]
__schedule+0x10e9/0x6820 kernel/sched/core.c:7188
preempt_schedule_common+0x42/0xc0 kernel/sched/core.c:7369
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__raw_spin_unlock include/linux/spinlock_api_smp.h:169 [inline]
_raw_spin_unlock+0x3e/0x50 kernel/locking/spinlock.c:190
spin_unlock include/linux/spinlock.h:390 [inline]
wp_page_copy mm/memory.c:3960 [inline]
do_wp_page+0x13d2/0x4350 mm/memory.c:4320
handle_pte_fault mm/memory.c:6427 [inline]
__handle_mm_fault+0x1ab6/0x2a00 mm/memory.c:6549
handle_mm_fault+0x36d/0xa20 mm/memory.c:6718
do_user_addr_fault+0x74c/0x12f0 arch/x86/mm/fault.c:1385
handle_page_fault arch/x86/mm/fault.c:1474 [inline]
exc_page_fault+0x6f/0xd0 arch/x86/mm/fault.c:1527
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0010:__put_user_nocheck_4+0x3/0x10 arch/x86/lib/putuser.S:104
Code: d9 0f 01 cb 89 01 31 c9 0f 01 ca e9 87 d7 03 00 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 01 cb <89> 01 31 c9 0f 01 ca c3 cc cc cc cc 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc9000ad2f9d8 EFLAGS: 00050202
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00002000002d2030
RDX: ffff88802aba2500 RSI: ffffffff895d3711 RDI: 0000000000400000
RBP: ffffc9000ad2fd78 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000002 R11: 000000000007fffc R12: 0000000000000000
R13: 00002000002d2000 R14: ffffc9000ad2fdbc R15: 0000000000000002
____sys_recvmsg+0x2ec/0x640 net/socket.c:2931
___sys_recvmsg+0x16a/0x1a0 net/socket.c:2960
do_recvmmsg+0x301/0x760 net/socket.c:3055
__sys_recvmmsg net/socket.c:3129 [inline]
__do_sys_recvmmsg net/socket.c:3152 [inline]
__se_sys_recvmmsg net/socket.c:3145 [inline]
__x64_sys_recvmmsg+0x22a/0x280 net/socket.c:3145
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x10b/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fddff79cdd9
RSP: 002b:00007fde006f1028 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007fddffa16090 RCX: 00007fddff79cdd9
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000003
RBP: 00007fddff832d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fddffa16128 R14: 00007fddffa16090 R15: 00007ffef430edf8
rcu: rcu_preempt kthread starved for 10495 jiffies! g105673 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:27848 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5387 [inline]
__schedule+0x10e9/0x6820 kernel/sched/core.c:7188
preempt_schedule_common+0x42/0xc0 kernel/sched/core.c:7369
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:179 [inline]
_raw_spin_unlock_irqrestore+0x61/0x80 kernel/locking/spinlock.c:198
debug_object_free+0x28d/0x550 lib/debugobjects.c:992
schedule_timeout+0x137/0x280 kernel/time/sleep_timeout.c:103
rcu_gp_fqs_loop+0x1a9/0x900 kernel/rcu/tree.c:2095
rcu_gp_kthread+0x179/0x230 kernel/rcu/tree.c:2297
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 16380 Comm: syz.3.2652 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:find_held_lock+0x66/0x80 kernel/locking/lockdep.c:5371
Code: eb 26 4c 89 e6 48 89 df e8 37 d3 b5 09 85 c0 75 19 83 ed 01 48 83 eb 28 83 fd ff 74 0b 0f b6 43 49 32 43 21 a8 60 74 da 31 db <41> 89 6d 00 48 89 d8 5b 5d 41 5c 41 5d 41 5e c3 cc cc cc cc 66 0f
RSP: 0018:ffffc90000007b98 EFLAGS: 00000002
RAX: 0000000000000001 RBX: ffff888059118bb8 RCX: ffffc90000007bd4
RDX: 0000000000000002 RSI: ffff88802a8562c0 RDI: ffff888059118bb8
RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: ffff88802a8562c0
R13: ffffc90000007bd4 R14: 0000000000000002 R15: 0000000000000002
FS: 00007f90ac68a6c0(0000) GS:ffff8881242db000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f90ac667ff8 CR3: 0000000045dfd000 CR4: 00000000003526f0
Call Trace:
__lock_release kernel/locking/lockdep.c:5535 [inline]
lock_release kernel/locking/lockdep.c:5889 [inline]
lock_release+0xdb/0x310 kernel/locking/lockdep.c:5875
__raw_spin_unlock include/linux/spinlock_api_smp.h:167 [inline]
_raw_spin_unlock+0x16/0x50 kernel/locking/spinlock.c:190
spin_unlock include/linux/spinlock.h:390 [inline]
advance_sched+0x62b/0xc80 net/sched/sch_taprio.c:987
__run_hrtimer kernel/time/hrtimer.c:1930 [inline]
__hrtimer_run_queues+0x470/0xa00 kernel/time/hrtimer.c:1994
hrtimer_interrupt+0x3e5/0x940 kernel/time/hrtimer.c:2113
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
__sysvec_apic_timer_interrupt+0x10b/0x460 arch/x86/kernel/apic/apic.c:1067
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline]
sysvec_apic_timer_interrupt+0x51/0xc0 arch/x86/kernel/apic/apic.c:1061
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:179 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x80 kernel/locking/spinlock.c:198
Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 66 b2 47 f6 48 89 df e8 3e 02 48 f6 f7 c5 00 02 00 00 75 23 9c 58 f6 c4 02 75 37 01 00 00 00 e8 25 d7 37 f6 65 8b 05 3e 9f 76 08 85 c0 74 16 5b
RSP: 0018:ffffc90000007f08 EFLAGS: 00000246
RAX: 0000000000000006 RBX: ffff8880b84284c0 RCX: 0000000000000004
RDX: 0000000000000000 RSI: ffffffff8df5a4df RDI: ffffffff8c1c2200
RBP: 0000000000000287 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffffffff8e40a100
R13: 0000000000000008 R14: 0000000000000100 R15: 0000000000000000
handle_softirqs+0x1ea/0xa00 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0x162/0x210 kernel/softirq.c:735
irq_exit_rcu+0x9/0x30 kernel/softirq.c:752
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline]
sysvec_apic_timer_interrupt+0xa3/0xc0 arch/x86/kernel/apic/apic.c:1061
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:finish_task_switch.isra.0+0x2d3/0x1010 kernel/sched/core.c:5244
Code: 2f 0a 00 00 41 c7 87 e0 0d 00 00 00 00 00 00 e9 0f 04 00 00 49 8d 7f 48 e8 7a 7e c7 09 e8 b5 8b 3b 00 fb 48 8d bb a8 16 00 00 <48> b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 0f b6 04 02 84
RSP: 0018:ffffc9000ad4f5e8 EFLAGS: 00000202
RAX: 0000000000017b15 RBX: ffff888059118000 RCX: 0000000000000040
RDX: 0000000000000000 RSI: ffffffff8df5a4df RDI: ffff8880591196a8
RBP: ffffc9000ad4f640 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: ffffffff81d62fc2 R12: ffff88801efe0000
R13: 0000000000000000 R14: dffffc0000000000 R15: ffff8880b843b240
context_switch kernel/sched/core.c:5390 [inline]
__schedule+0x10f1/0x6820 kernel/sched/core.c:7188
preempt_schedule_common+0x42/0xc0 kernel/sched/core.c:7369
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:179 [inline]
_raw_spin_unlock_irqrestore+0x61/0x80 kernel/locking/spinlock.c:198
__unix_dgram_recvmsg+0x31a/0xc30 net/unix/af_unix.c:2602
unix_dgram_recvmsg+0xcd/0x100 net/unix/af_unix.c:2676
sock_recvmsg_nosec net/socket.c:1137 [inline]
____sys_recvmsg+0x5b3/0x640 net/socket.c:2916
___sys_recvmsg+0x16a/0x1a0 net/socket.c:2960
do_recvmmsg+0x301/0x760 net/socket.c:3055
__sys_recvmmsg net/socket.c:3129 [inline]
__do_sys_recvmmsg net/socket.c:3152 [inline]
__se_sys_recvmmsg net/socket.c:3145 [inline]
__x64_sys_recvmmsg+0x22a/0x280 net/socket.c:3145
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x10b/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f90ab79cdd9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f90ac68a028 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007f90aba16090 RCX: 00007f90ab79cdd9
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000006
RBP: 00007f90ab832d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f90aba16128 R14: 00007f90aba16090 R15: 00007ffe71585ba8