syzbot

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P16838/1:b..l
rcu: 	(detected by 0, t=10503 jiffies, g=180337, q=1665625 ncpus=2)
task:syz-executor    state:R  running task     stack:20704 pid:16838 tgid:16838 ppid:16827  flags:0x20004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5322 [inline]
 __schedule+0x1895/0x4b30 kernel/sched/core.c:6682
 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7004
 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:unwind_next_frame+0xd/0x22d0 arch/x86/kernel/unwind_orc.c:469
Code: 7c 91 4c 89 f7 e8 83 31 bd 00 eb 87 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 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 bc 00 00 00 00 00 fc ff df 48
RSP: 0018:ffffc90003bef250 EFLAGS: 00000202
RAX: 0000000000000001 RBX: ffffc90003bef280 RCX: ffffffff917bb000
RDX: dffffc0000000000 RSI: ffffffff81551d95 RDI: ffffc90003bef280
RBP: ffffc90003bef310 R08: 000000000000000a R09: ffffc90003bef370
R10: ffffc90003bef2d0 R11: ffffffff8180a0e0 R12: ffff88802ed1da00
R13: ffffffff8180a0e0 R14: ffffc90003bef360 R15: 0000000000000000
 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122
 save_stack+0xfb/0x1f0 mm/page_owner.c:156
 __reset_page_owner+0x76/0x430 mm/page_owner.c:297
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1108 [inline]
 free_unref_page+0xcfb/0xf20 mm/page_alloc.c:2638
 discard_slab mm/slub.c:2677 [inline]
 __put_partials+0xeb/0x130 mm/slub.c:3145
 put_cpu_partial+0x17c/0x250 mm/slub.c:3220
 __slab_free+0x2ea/0x3d0 mm/slub.c:4449
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:247 [inline]
 slab_post_alloc_hook mm/slub.c:4085 [inline]
 slab_alloc_node mm/slub.c:4134 [inline]
 kmem_cache_alloc_noprof+0x135/0x2a0 mm/slub.c:4141
 vm_area_dup+0x27/0x290 kernel/fork.c:487
 dup_mmap kernel/fork.c:696 [inline]
 dup_mm kernel/fork.c:1674 [inline]
 copy_mm+0xc94/0x1f40 kernel/fork.c:1723
 copy_process+0x1845/0x3d50 kernel/fork.c:2372
 kernel_clone+0x226/0x8f0 kernel/fork.c:2784
 __do_compat_sys_ia32_clone arch/x86/kernel/sys_ia32.c:254 [inline]
 __se_compat_sys_ia32_clone arch/x86/kernel/sys_ia32.c:240 [inline]
 __ia32_compat_sys_ia32_clone+0x255/0x2a0 arch/x86/kernel/sys_ia32.c:240
 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
 __do_fast_syscall_32+0xb4/0x110 arch/x86/entry/common.c:386
 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:411
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf7f23579
RSP: 002b:00000000f750fcdc EFLAGS: 00000206 ORIG_RAX: 0000000000000078
RAX: ffffffffffffffda RBX: 0000000001200011 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000056bfa4a8
RBP: 00000000f73abff4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
rcu: rcu_preempt kthread starved for 2178 jiffies! g180337 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:25888 pid:17    tgid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5322 [inline]
 __schedule+0x1895/0x4b30 kernel/sched/core.c:6682
 __schedule_loop kernel/sched/core.c:6759 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6774
 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2615
 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2045
 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2247
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </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: 5285 Comm: kworker/1:6 Not tainted 6.12.0-rc2-syzkaller-00320-gba01565ced22 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: events nsim_dev_trap_report_work
RIP: 0010:unwind_next_frame+0x7/0x22d0 arch/x86/kernel/unwind_orc.c:469
Code: 07 80 c1 03 38 c1 7c 91 4c 89 f7 e8 83 31 bd 00 eb 87 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 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 bc 00 00 00
RSP: 0018:ffffc90000a17788 EFLAGS: 00000202
RAX: 0000000000000001 RBX: ffffc90000a177a0 RCX: ffffffff917bb000
RDX: dffffc0000000000 RSI: ffffffff81fe6396 RDI: ffffc90000a177a0
RBP: ffffc90000a17830 R08: 0000000000000001 R09: ffffc90000a17890
R10: ffffc90000a177f0 R11: ffffffff8180a0e0 R12: ffff8880329b0000
R13: ffffffff8180a0e0 R14: ffffc90000a17880 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000c2c0129 CR3: 000000000e734000 CR4: 00000000003526f0
DR0: 0000000000001000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000010000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
 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:319 [inline]
 __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:345
 kasan_slab_alloc include/linux/kasan.h:247 [inline]
 slab_post_alloc_hook mm/slub.c:4085 [inline]
 slab_alloc_node mm/slub.c:4134 [inline]
 kmem_cache_alloc_noprof+0x135/0x2a0 mm/slub.c:4141
 dst_alloc+0x12b/0x190 net/core/dst.c:89
 rt_dst_alloc net/ipv4/route.c:1612 [inline]
 __mkroute_output net/ipv4/route.c:2573 [inline]
 ip_route_output_key_hash_rcu+0x13cc/0x2390 net/ipv4/route.c:2795
 ip_route_output_key_hash+0x193/0x2b0 net/ipv4/route.c:2624
 __ip_route_output_key include/net/route.h:141 [inline]
 ip_route_output_flow+0x29/0x140 net/ipv4/route.c:2852
 ip_route_output_key include/net/route.h:151 [inline]
 ip_route_me_harder+0x80d/0x1300 net/ipv4/netfilter.c:53
 synproxy_send_tcp+0x356/0x6c0 net/netfilter/nf_synproxy_core.c:431
 synproxy_send_client_synack+0x8b8/0xf30 net/netfilter/nf_synproxy_core.c:484
 nft_synproxy_eval_v4+0x3ca/0x610 net/netfilter/nft_synproxy.c:59
 nft_synproxy_do_eval+0x362/0xa60 net/netfilter/nft_synproxy.c:141
 expr_call_ops_eval net/netfilter/nf_tables_core.c:240 [inline]
 nft_do_chain+0x4ad/0x1da0 net/netfilter/nf_tables_core.c:288
 nft_do_chain_inet+0x418/0x6b0 net/netfilter/nft_chain_filter.c:161
 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline]
 nf_hook_slow+0xc3/0x220 net/netfilter/core.c:626
 nf_hook include/linux/netfilter.h:269 [inline]
 NF_HOOK+0x29e/0x450 include/linux/netfilter.h:312
 NF_HOOK+0x3a4/0x450 include/linux/netfilter.h:314
 __netif_receive_skb_one_core net/core/dev.c:5666 [inline]
 __netif_receive_skb+0x2bf/0x650 net/core/dev.c:5779
 process_backlog+0x662/0x15b0 net/core/dev.c:6111
 __napi_poll+0xcb/0x490 net/core/dev.c:6775
 napi_poll net/core/dev.c:6844 [inline]
 net_rx_action+0x89b/0x1240 net/core/dev.c:6966
 handle_softirqs+0x2c5/0x980 kernel/softirq.c:554
 do_softirq+0x11b/0x1e0 kernel/softirq.c:455
 </IRQ>
 <TASK>
 __local_bh_enable_ip+0x1bb/0x200 kernel/softirq.c:382
 spin_unlock_bh include/linux/spinlock.h:396 [inline]
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:820 [inline]
 nsim_dev_trap_report_work+0x75d/0xaa0 drivers/net/netdevsim/dev.c:850
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310
 worker_thread+0x870/0xd30 kernel/workqueue.c:3391
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>