rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P7324/1:b..l P7317/1:b..l
rcu: 	(detected by 0, t=10502 jiffies, g=24613, q=190 ncpus=2)
task:syz.2.381       state:R  running task     stack:24584 pid:7317  ppid:5777   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5381 [inline]
 __schedule+0x15ae/0x4660 kernel/sched/core.c:6700
 preempt_schedule_irq+0xbf/0x150 kernel/sched/core.c:7010
 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:unwind_next_frame+0x9/0x2990 arch/x86/kernel/unwind_orc.c:469
Code: e1 07 80 c1 03 38 c1 0f 8c 64 ff ff ff 48 89 df e8 dc 35 a4 00 e9 57 ff ff ff 0f 1f 80 00 00 00 00 f3 0f 1e fa 55 41 57 41 56 <41> 55 41 54 53 48 81 ec 98 00 00 00 49 89 fd 49 bf 00 00 00 00 00
RSP: 0018:ffffc9000fabef88 EFLAGS: 00000202
RAX: 0000000000000001 RBX: ffffc9000fabf060 RCX: ffff888024655a00
RDX: dffffc0000000000 RSI: ffffffff8a8390a5 RDI: ffffc9000fabefa8
RBP: ffffc9000fabf030 R08: ffffc9000fabf070 R09: 000000000000000d
R10: 0000000000000004 R11: 0000000000000002 R12: ffffffff8a8390a5
R13: 00000000000000b8 R14: ffffffff81758be0 R15: ffffc9000fabefa8
 arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0xaa/0x100 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:46 [inline]
 kasan_set_track+0x4e/0x70 mm/kasan/common.c:53
 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:188 [inline]
 slab_post_alloc_hook+0x6a/0x4d0 mm/slab.h:767
 slab_alloc_node mm/slub.c:3495 [inline]
 slab_alloc mm/slub.c:3503 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3510 [inline]
 kmem_cache_alloc+0x17e/0x2c0 mm/slub.c:3519
 dst_alloc+0x105/0x170 net/core/dst.c:90
 rt_dst_alloc net/ipv4/route.c:1662 [inline]
 __mkroute_output net/ipv4/route.c:2626 [inline]
 ip_route_output_key_hash_rcu+0x14a2/0x2350 net/ipv4/route.c:2848
 ip_route_output_key_hash+0x1f3/0x330 net/ipv4/route.c:2677
 __ip_route_output_key include/net/route.h:134 [inline]
 ip_route_output_flow+0x2a/0x150 net/ipv4/route.c:2905
 udp_sendmsg+0x160e/0x23d0 net/ipv4/udp.c:1236
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg net/socket.c:745 [inline]
 ____sys_sendmsg+0x61b/0x980 net/socket.c:2595
 ___sys_sendmsg+0x2a6/0x360 net/socket.c:2649
 __sys_sendmmsg+0x2ca/0x510 net/socket.c:2735
 __do_sys_sendmmsg net/socket.c:2764 [inline]
 __se_sys_sendmmsg net/socket.c:2761 [inline]
 __x64_sys_sendmmsg+0xa0/0xb0 net/socket.c:2761
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fcb2559ce59
RSP: 002b:00007fcb2636e028 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007fcb25815fa0 RCX: 00007fcb2559ce59
RDX: 000000000800001d RSI: 0000200000007fc0 RDI: 0000000000000003
RBP: 00007fcb25632e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fcb25816038 R14: 00007fcb25815fa0 R15: 00007ffc9f32ee18
 </TASK>
task:syz.2.381       state:R  running task     stack:27048 pid:7324  ppid:5777   flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5381 [inline]
 __schedule+0x15ae/0x4660 kernel/sched/core.c:6700
 preempt_schedule_irq+0xbf/0x150 kernel/sched/core.c:7010
 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:__sanitizer_cov_trace_pc+0x5c/0x60 kernel/kcov.c:234
Code: f8 15 00 00 83 fa 02 75 21 48 8b 91 00 16 00 00 48 8b 32 48 8d 7e 01 8b 89 fc 15 00 00 48 39 cf 73 08 48 89 3a 48 89 44 f2 08 <c3> 0f 1f 00 f3 0f 1e fa 48 8b 04 24 65 48 8b 15 80 d2 7c 7e 65 8b
RSP: 0018:ffffc9000facfed0 EFLAGS: 00000283
RAX: ffffffff81594c30 RBX: ffffc9000facff20 RCX: 0000000000080000
RDX: ffffc90011d68000 RSI: 0000000000000851 RDI: 0000000000000852
RBP: 0000000000000001 R08: dffffc0000000000 R09: 1ffffffff22378a0
R10: dffffc0000000000 R11: fffffbfff22378a1 R12: 0000000000000001
R13: 0000000000000000 R14: 0000000000000000 R15: ffff88802c568000
 rcu_read_lock include/linux/rcupdate.h:787 [inline]
 __task_pid_nr_ns+0x70/0x470 kernel/pid.c:500
 task_tgid_vnr include/linux/sched.h:1649 [inline]
 __ia32_sys_getpid+0x1d/0x20 kernel/sys.c:960
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fcb25596bd7
RSP: 002b:00007fcb22f8ea48 EFLAGS: 00000206 ORIG_RAX: 0000000000000027
RAX: ffffffffffffffda RBX: 00007fcb22f8ebb0 RCX: 00007fcb25596bd7
RDX: 00007fcb22f8ea80 RSI: 00007fcb22f8ebb0 RDI: 0000000000000021
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007fcb258163f8 R14: 00007fcb25816360 R15: 00007ffc9f32ee18
 </TASK>
rcu: rcu_preempt kthread starved for 10186 jiffies! g24613 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:26504 pid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5381 [inline]
 __schedule+0x15ae/0x4660 kernel/sched/core.c:6700
 schedule+0xbd/0x170 kernel/sched/core.c:6774
 schedule_timeout+0x188/0x2d0 kernel/time/timer.c:2168
 rcu_gp_fqs_loop+0x30d/0x1590 kernel/rcu/tree.c:1667
 rcu_gp_kthread+0x9d/0x3b0 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:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:pv_native_safe_halt+0xf/0x10 arch/x86/kernel/paravirt.c:148
Code: dc 23 02 c3 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 43 67 44 00 fb f4 <c3> 66 0f 1f 00 55 41 57 41 56 41 54 53 50 8b 2f eb 2c 89 cb 80 f9
RSP: 0018:ffffffff8ce07d80 EFLAGS: 000002c6
RAX: d737b4ae6e5ceb00 RBX: ffffffff81628b01 RCX: d737b4ae6e5ceb00
RDX: 0000000000000001 RSI: ffffffff8acacb60 RDI: ffffffff8b1c7be0
RBP: ffffffff8ce07eb8 R08: ffff8880b8e36bab R09: 1ffff110171c6d75
R10: dffffc0000000000 R11: ffffed10171c6d76 R12: 1ffffffff19c0fbc
R13: dffffc0000000000 R14: 1ffffffff19d2688 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1d0a4bd951 CR3: 000000002e245000 CR4: 00000000003506f0
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:178 [inline]
 do_idle+0x221/0x5c0 kernel/sched/idle.c:302
 cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:401
 rest_init+0x2e2/0x300 init/main.c:744
 arch_call_rest_init+0xe/0x10 init/main.c:840
 start_kernel+0x459/0x4e0 init/main.c:1085
 x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:555
 x86_64_start_kernel+0x60/0x60 arch/x86/kernel/head64.c:536
 secondary_startup_64_no_verify+0x179/0x17b
 </TASK>