rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P17595/1:b..l
rcu: 	(detected by 0, t=10502 jiffies, g=118093, q=574302 ncpus=2)
task:syz.5.2791      state:R  running task     stack:24792 pid:17595 tgid:17589 ppid:17255  task_flags:0x400040 flags:0x10080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7256
 irqentry_exit+0x6f/0x90 kernel/entry/common.c:211
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_release+0x2b5/0x3e0 kernel/locking/lockdep.c:5893
Code: 51 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f7 44 24 20 00 02 00 00 75 56 f7 c3 00 02 00 00 74 01 fb 65 48 8b 05 3b ca d0 10 <48> 3b 44 24 28 0f 85 8b 00 00 00 48 83 c4 30 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc9000afb6970 EFLAGS: 00000206
RAX: d56f4f3b4f91aa00 RBX: 0000000000000202 RCX: d56f4f3b4f91aa00
RDX: 0000000000000001 RSI: ffffffff8d8f3f04 RDI: ffffffff8bbf0760
RBP: ffff88803f2b47d8 R08: ffffc9000afb6bd0 R09: 0000000000000000
R10: ffffc9000afb6af8 R11: fffff520015f6d61 R12: 0000000000000001
R13: 0000000000000001 R14: ffffffff8df3d660 R15: ffff88803f2b3c80
 rcu_lock_release include/linux/rcupdate.h:341 [inline]
 rcu_read_unlock include/linux/rcupdate.h:897 [inline]
 class_rcu_destructor include/linux/rcupdate.h:1195 [inline]
 unwind_next_frame+0x19a9/0x2390 arch/x86/kernel/unwind_orc.c:680
 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:56 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
 unpoison_slab_object mm/kasan/common.c:342 [inline]
 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:368
 kasan_slab_alloc include/linux/kasan.h:252 [inline]
 slab_post_alloc_hook mm/slub.c:4970 [inline]
 slab_alloc_node mm/slub.c:5280 [inline]
 kmem_cache_alloc_node_noprof+0x433/0x710 mm/slub.c:5332
 kmalloc_reserve+0xbd/0x290 net/core/skbuff.c:579
 __alloc_skb+0x142/0x2d0 net/core/skbuff.c:670
 alloc_skb include/linux/skbuff.h:1383 [inline]
 _sctp_make_chunk+0x5e/0x430 net/sctp/sm_make_chunk.c:1435
 sctp_make_control net/sctp/sm_make_chunk.c:1482 [inline]
 sctp_make_cookie_ack+0x34/0x2d0 net/sctp/sm_make_chunk.c:616
 sctp_sf_do_dupcook_d+0x3bb/0xa90 net/sctp/sm_statefuns.c:2155
 sctp_sf_do_5_2_4_dupcook+0xac4/0x12e0 net/sctp/sm_statefuns.c:2306
 sctp_do_sm+0x1e7/0x5a20 net/sctp/sm_sideeffect.c:1172
 sctp_assoc_bh_rcv+0x3f2/0x630 net/sctp/associola.c:1034
 sctp_backlog_rcv+0x167/0x3f0 net/sctp/input.c:331
 sk_backlog_rcv include/net/sock.h:1158 [inline]
 __release_sock+0x297/0x3a0 net/core/sock.c:3180
 release_sock+0x5f/0x1f0 net/core/sock.c:3735
 sctp_wait_for_connect+0x37d/0x680 net/sctp/socket.c:9340
 sctp_sendmsg_to_asoc+0x13bb/0x1810 net/sctp/socket.c:1885
 sctp_sendmsg+0x1941/0x2810 net/sctp/socket.c:2031
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg+0x19c/0x270 net/socket.c:742
 __sys_sendto+0x3bd/0x520 net/socket.c:2244
 __do_sys_sendto net/socket.c:2251 [inline]
 __se_sys_sendto net/socket.c:2247 [inline]
 __ia32_sys_sendto+0xdd/0x100 net/socket.c:2247
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 __do_fast_syscall_32+0xb6/0x2b0 arch/x86/entry/syscall_32.c:306
 do_fast_syscall_32+0x34/0x80 arch/x86/entry/syscall_32.c:331
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf7f27539
RSP: 002b:00000000f4fb155c EFLAGS: 00000206 ORIG_RAX: 0000000000000171
RAX: ffffffffffffffda RBX: 0000000000000008 RCX: 0000000080847fff
RDX: 0000000000034000 RSI: 0000000000000000 RDI: 000000008005ffe4
RBP: 000000000000001c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
rcu: rcu_preempt kthread starved for 6987 jiffies! g118093 f0x2 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:27224 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
 __schedule_loop kernel/sched/core.c:7011 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:7026
 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+0x4bc/0x870 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: cc cc cc cc 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 f3 f1 21 00 f3 0f 1e fa fb f4 <e9> c8 e6 02 00 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90000197de0 EFLAGS: 000002c6
RAX: 36e2ac5e78629f00 RBX: ffffffff81967bf7 RCX: 36e2ac5e78629f00
RDX: 0000000000000001 RSI: ffffffff8d70d481 RDI: ffffffff8bbf0760
RBP: ffffc90000197f10 R08: ffff8880b8932fdb R09: 1ffff110171265fb
R10: dffffc0000000000 R11: ffffed10171265fc R12: ffffffff8f7cdc70
R13: 0000000000000001 R14: 0000000000000001 R15: 1ffff110039d3b58
FS:  0000000000000000(0000) GS:ffff88812623d000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000008001d018 CR3: 0000000065fc4000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 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:190 [inline]
 do_idle+0x1e7/0x510 kernel/sched/idle.c:330
 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:428
 start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:315
 common_startup_64+0x13e/0x147
 </TASK>