rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: (detected by 1, t=10502 jiffies, g=9853, q=860 ncpus=2) rcu: All QSes seen, last rcu_preempt kthread activity 10503 (4294961068-4294950565), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 10504 jiffies! g9853 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:27064 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5241 [inline] __schedule+0x143f/0x4570 kernel/sched/core.c:6558 schedule+0xbf/0x180 kernel/sched/core.c:6634 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1965 rcu_gp_fqs_loop+0x2d2/0x1150 kernel/rcu/tree.c:1706 rcu_gp_kthread+0xa3/0x3b0 kernel/rcu/tree.c:1905 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 PID: 4013 Comm: syz.3.65 Not tainted 6.1.112-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:on_stack arch/x86/include/asm/stacktrace.h:60 [inline] RIP: 0010:stack_access_ok arch/x86/kernel/unwind_orc.c:347 [inline] RIP: 0010:deref_stack_reg arch/x86/kernel/unwind_orc.c:357 [inline] RIP: 0010:unwind_next_frame+0xc7c/0x2220 arch/x86/kernel/unwind_orc.c:539 Code: 8b 4c 24 28 0f b6 04 01 84 c0 0f 85 c7 10 00 00 48 8b 44 24 08 4c 8d 68 f8 41 83 3c 24 00 74 1c 4d 39 ee 77 17 4c 39 eb 76 12 <49> 8d 45 08 4c 39 f0 76 09 48 39 d8 0f 86 c7 00 00 00 48 8b 1c 24 RSP: 0018:ffffc900001e03e0 EFLAGS: 00000216 RAX: ffffc900001e0c80 RBX: ffffc900001e1000 RCX: 1ffff9200003c098 RDX: 1ffffffff1e32566 RSI: 0000000000000000 RDI: dffffc0000000000 RBP: 1ffff9200003c09a R08: 0000000000000001 R09: ffffc900001e05b0 R10: 0000000000000000 R11: dffffc0000000001 R12: ffffc900001e04c0 R13: ffffc900001e0c78 R14: ffffc900001d9000 R15: 1ffff9200003c099 FS: 00007fd4ee3ff6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000002000cf3d CR3: 00000000633d8000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: arch_stack_walk+0x10d/0x140 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x113/0x1c0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:516 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1724 [inline] slab_free_freelist_hook mm/slub.c:1750 [inline] slab_free mm/slub.c:3661 [inline] __kmem_cache_free+0x25c/0x3c0 mm/slub.c:3674 skb_free_head net/core/skbuff.c:762 [inline] skb_release_data+0x5de/0x7a0 net/core/skbuff.c:791 skb_release_all net/core/skbuff.c:856 [inline] __kfree_skb+0x4c/0x60 net/core/skbuff.c:870 tcp_write_queue_purge+0x132/0x2f0 net/ipv4/tcp.c:3099 tcp_done_with_error+0x3d/0xc0 net/ipv4/tcp_input.c:4366 tcp_write_err net/ipv4/tcp_timer.c:70 [inline] tcp_write_timeout net/ipv4/tcp_timer.c:273 [inline] tcp_retransmit_timer+0x12ca/0x2800 net/ipv4/tcp_timer.c:547 tcp_write_timer+0x12e/0x280 net/ipv4/tcp_timer.c:676 call_timer_fn+0x1ad/0x6b0 kernel/time/timer.c:1504 expire_timers kernel/time/timer.c:1549 [inline] __run_timers+0x67c/0x890 kernel/time/timer.c:1820 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1833 handle_softirqs+0x2ee/0xa40 kernel/softirq.c:571 __do_softirq kernel/softirq.c:605 [inline] invoke_softirq kernel/softirq.c:445 [inline] __irq_exit_rcu+0x157/0x240 kernel/softirq.c:654 irq_exit_rcu+0x5/0x20 kernel/softirq.c:666 sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1106 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653 RIP: 0010:preempt_latency_start kernel/sched/core.c:5690 [inline] RIP: 0010:preempt_count_add+0xb8/0x180 kernel/sched/core.c:5713 Code: 00 85 c0 74 0a 45 31 f6 31 ff e8 a3 59 0d 00 65 48 8b 1d ab f8 a3 7e 48 81 c3 d8 14 00 00 48 89 d8 48 c1 e8 03 42 80 3c 38 00 <74> 08 48 89 df e8 4e bb 83 00 4c 89 33 5b 41 5e 41 5f c3 e8 70 1a RSP: 0018:ffffc900033cf6a0 EFLAGS: 00000246 RAX: 1ffff110032f929b RBX: ffff8880197c94d8 RCX: ffffffff8ab13d00 RDX: dffffc0000000000 RSI: ffffffff8893ae06 RDI: ffffffff813cb533 RBP: 1ffff92000679ef4 R08: 0000000000000005 R09: ffffc900033cf890 R10: 0000000000000000 R11: dffffc0000000001 R12: ffff8880197c8000 R13: ffffffff81786c50 R14: ffffffff813cb533 R15: dffffc0000000000 unwind_next_frame+0xb3/0x2220 arch/x86/kernel/unwind_orc.c:433 arch_stack_walk+0x10d/0x140 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x113/0x1c0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 __kasan_slab_alloc+0x65/0x70 mm/kasan/common.c:328 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x52/0x3a0 mm/slab.h:737 slab_alloc_node mm/slub.c:3398 [inline] slab_alloc mm/slub.c:3406 [inline] __kmem_cache_alloc_lru mm/slub.c:3413 [inline] kmem_cache_alloc+0x10c/0x2d0 mm/slub.c:3422 sk_prot_alloc+0x58/0x200 net/core/sock.c:2041 sk_alloc+0x36/0x350 net/core/sock.c:2100 unix_create1+0xb4/0x7f0 unix_create+0x146/0x1f0 net/unix/af_unix.c:1011 __sock_create+0x488/0x910 net/socket.c:1550 sock_create net/socket.c:1601 [inline] __sys_socketpair+0x335/0x700 net/socket.c:1732 __do_sys_socketpair net/socket.c:1781 [inline] __se_sys_socketpair net/socket.c:1778 [inline] __x64_sys_socketpair+0x97/0xb0 net/socket.c:1778 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fd4ee57dff9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fd4ee3ff038 EFLAGS: 00000246 ORIG_RAX: 0000000000000035 RAX: ffffffffffffffda RBX: 00007fd4ee735f80 RCX: 00007fd4ee57dff9 RDX: 0000000000000000 RSI: 0000000000000005 RDI: 0000000000000001 RBP: 00007fd4ee5f0296 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000020000740 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fd4ee735f80 R15: 00007ffe17d01548