syzbot

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 1, t=10502 jiffies, g=25437, q=222 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4294966090-4294955588), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread starved for 10502 jiffies! g25437 f0x2 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:24656 pid:16    tgid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5409 [inline]
 __schedule+0x17d3/0x4a20 kernel/sched/core.c:6736
 __schedule_loop kernel/sched/core.c:6813 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6828
 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2572
 rcu_gp_fqs_loop+0x2df/0x1370 kernel/rcu/tree.c:1663
 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:1862
 kthread+0x2f2/0x390 kernel/kthread.c:388
 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 8031 Comm: syz-executor.1 Not tainted 6.8.0-syzkaller-08951-gfe46a7dd189e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
RIP: 0010:_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
RIP: 0010:cpumask_test_cpu include/linux/cpumask.h:505 [inline]
RIP: 0010:cpu_online include/linux/cpumask.h:1120 [inline]
RIP: 0010:trace_hrtimer_start include/trace/events/timer.h:222 [inline]
RIP: 0010:debug_activate kernel/time/hrtimer.c:479 [inline]
RIP: 0010:enqueue_hrtimer+0x5d/0x3a0 kernel/time/hrtimer.c:1090
Code: 00 00 e8 36 46 12 00 65 8b 2d 6b 21 81 7e bf 07 00 00 00 89 ee e8 63 4a 12 00 83 fd 07 0f 87 6c 01 00 00 e8 15 46 12 00 89 eb <48> 89 d8 48 c1 e8 06 48 8d 3c c5 68 3a 87 8f be 08 00 00 00 e8 8a
RSP: 0018:ffffc90000007d28 EFLAGS: 00000046
RAX: ffffffff8182af3b RBX: 0000000000000000 RCX: ffff8880294c5a00
RDX: 0000000000010202 RSI: 0000000000000000 RDI: 0000000000000007
RBP: 0000000000000000 R08: ffffffff8182af2d R09: 1ffffffff28d85ca
R10: dffffc0000000000 R11: fffffbfff28d85cb R12: dffffc0000000000
R13: ffff8880b942c9c0 R14: ffff88802b7d7340 R15: ffff8880b942c8c0
FS:  00007fa1c096b6c0(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f236c5ad988 CR3: 000000002eff6000 CR4: 0000000000350ef0
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 __run_hrtimer kernel/time/hrtimer.c:1709 [inline]
 __hrtimer_run_queues+0x6b5/0xd00 kernel/time/hrtimer.c:1756
 hrtimer_interrupt+0x396/0x990 kernel/time/hrtimer.c:1818
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1032 [inline]
 __sysvec_apic_timer_interrupt+0x109/0x3a0 arch/x86/kernel/apic/apic.c:1049
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1043
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:check_kcov_mode kernel/kcov.c:184 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:236 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x35/0x90 kernel/kcov.c:304
Code: 14 25 80 d0 03 00 65 8b 05 e0 d6 6e 7e a9 00 01 ff 00 74 10 a9 00 01 00 00 74 5b 83 ba 14 16 00 00 00 74 52 8b 82 f0 15 00 00 <83> f8 03 75 47 48 8b 8a f8 15 00 00 44 8b 8a f4 15 00 00 49 c1 e1
RSP: 0018:ffffc9000531f670 EFLAGS: 00000246
RAX: 0000000000000002 RBX: ffffc9000531f6e8 RCX: ffffffff90daa000
RDX: ffff8880294c5a00 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffffff81408e18 R09: 1ffffffff1f0e74d
R10: dffffc0000000000 R11: fffffbfff1f0e74e R12: ffff8880294c5a00
R13: ffffffff8180e0a0 R14: dffffc0000000000 R15: 1ffff92000a63edd
 unwind_get_return_address+0x68/0xc0 arch/x86/kernel/unwind_orc.c:369
 arch_stack_walk+0x125/0x1b0 arch/x86/kernel/stacktrace.c:26
 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 unpoison_slab_object mm/kasan/common.c:312 [inline]
 __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:338
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slub.c:3798 [inline]
 slab_alloc_node mm/slub.c:3845 [inline]
 kmem_cache_alloc+0x174/0x340 mm/slub.c:3852
 sctp_bucket_create net/sctp/socket.c:8707 [inline]
 sctp_get_port_local+0x78e/0x1740 net/sctp/socket.c:8457
 sctp_do_bind+0x513/0x950 net/sctp/socket.c:432
 sctp_bind+0x9c/0x100 net/sctp/socket.c:320
 inet6_bind_sk+0x108/0x300 net/ipv6/af_inet6.c:453
 __sys_bind+0x23f/0x2f0 net/socket.c:1847
 __do_sys_bind net/socket.c:1858 [inline]
 __se_sys_bind net/socket.c:1856 [inline]
 __x64_sys_bind+0x7a/0x90 net/socket.c:1856
 do_syscall_64+0xfd/0x240
 entry_SYSCALL_64_after_hwframe+0x6d/0x75
RIP: 0033:0x7fa1bfc7de69
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fa1c096b0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000031
RAX: ffffffffffffffda RBX: 00007fa1bfdabf80 RCX: 00007fa1bfc7de69
RDX: 000000000000001c RSI: 0000000020000000 RDI: 0000000000000005
RBP: 00007fa1bfcca47a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007fa1bfdabf80 R15: 00007ffdbf8012e8
 </TASK>