rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (2 ticks this GP) idle=cc8c/1/0x4000000000000000 softirq=111807/111807 fqs=1 rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P18572/1:b..l rcu: (detected by 0, t=10503 jiffies, g=86417, q=65 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 18570 Comm: syz.9.2674 Not tainted 6.13.0-rc2-syzkaller-00018-g7cb1b4663150 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:advance_sched+0x13e/0xc60 net/sched/sch_taprio.c:927 Code: 85 84 0a 00 00 49 8b 46 e8 48 89 04 24 e8 ea ff e7 01 31 ff 89 c3 89 c6 e8 8f 2c 59 f8 85 db 0f 85 44 06 00 00 e8 42 2a 59 f8 <49> 8d 46 f0 48 89 c2 48 89 44 24 50 48 b8 00 00 00 00 00 fc ff df RSP: 0018:ffffc90000a18d80 EFLAGS: 00000046 RAX: 0000000080010001 RBX: 0000000000000001 RCX: ffffffff8940df9b RDX: ffff888030c04880 RSI: ffffffff8940d93e RDI: 0000000000000005 RBP: 000000000003d90c R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffff88806ae86340 R13: ffff8880b872cb00 R14: ffff88806ae86340 R15: ffffffff8940d800 FS: 00007f4a827bf6c0(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000004d91e000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 000000000000000b DR2: fffffffffffffffd DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __run_hrtimer kernel/time/hrtimer.c:1739 [inline] __hrtimer_run_queues+0x20a/0xae0 kernel/time/hrtimer.c:1803 hrtimer_interrupt+0x392/0x8e0 kernel/time/hrtimer.c:1865 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x10f/0x400 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:__might_fault mm/memory.c:6751 [inline] RIP: 0010:__might_fault+0xbc/0x190 mm/memory.c:6744 Code: 4d 21 7e 48 8d bb 48 05 00 00 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 be 00 00 00 48 83 bb 48 05 00 00 00 74 b0 e8 74 77 b7 ff <48> b8 00 00 00 00 00 fc ff df 65 48 8b 1d e2 4c 21 7e 48 8d bb 48 RSP: 0018:ffffc90002fe7a38 EFLAGS: 00000246 RAX: 0000000000080000 RBX: ffff888030c04880 RCX: ffffc9000fb1c000 RDX: 0000000000080000 RSI: ffffffff81e28c0c RDI: ffff888030c04dc8 RBP: 00000000000000a2 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: ffffc90002fe7aa8 R14: ffffc90002fe7b90 R15: ffffc90002fe7aa8 _inline_copy_from_user include/linux/uaccess.h:162 [inline] _copy_from_user+0x29/0xd0 lib/usercopy.c:18 copy_from_user include/linux/uaccess.h:212 [inline] copy_msghdr_from_user+0x99/0x160 net/socket.c:2513 recvmsg_copy_msghdr net/socket.c:2769 [inline] ___sys_recvmsg+0xdc/0x1a0 net/socket.c:2841 do_recvmmsg+0x2f8/0x740 net/socket.c:2940 __sys_recvmmsg net/socket.c:3014 [inline] __do_sys_recvmmsg net/socket.c:3037 [inline] __se_sys_recvmmsg net/socket.c:3030 [inline] __x64_sys_recvmmsg+0x239/0x290 net/socket.c:3030 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f4a8197ff19 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:00007f4a827bf058 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 00007f4a81b46080 RCX: 00007f4a8197ff19 RDX: 0000000000010106 RSI: 00000000200000c0 RDI: 0000000000000009 RBP: 00007f4a819f3cc8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f4a81b46080 R15: 00007ffdd1dcaaf8 task:syz.8.2678 state:R running task stack:26336 pid:18572 tgid:18571 ppid:14156 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0xe58/0x5ad0 kernel/sched/core.c:6756 preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:6935 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline] _raw_spin_unlock+0x3e/0x50 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:391 [inline] follow_page_pte+0x349/0x1b20 mm/gup.c:944 follow_pmd_mask mm/gup.c:991 [inline] follow_pud_mask mm/gup.c:1030 [inline] follow_p4d_mask mm/gup.c:1047 [inline] follow_page_mask mm/gup.c:1090 [inline] __get_user_pages+0x5ef/0x3b50 mm/gup.c:1492 populate_vma_page_range+0x27f/0x3a0 mm/gup.c:1932 __mm_populate+0x1d6/0x380 mm/gup.c:2035 mm_populate include/linux/mm.h:3386 [inline] vm_mmap_pgoff+0x293/0x360 mm/util.c:585 ksys_mmap_pgoff+0x7d/0x5c0 mm/mmap.c:542 __do_sys_mmap arch/x86/kernel/sys_x86_64.c:89 [inline] __se_sys_mmap arch/x86/kernel/sys_x86_64.c:82 [inline] __x64_sys_mmap+0x125/0x190 arch/x86/kernel/sys_x86_64.c:82 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f0e95d7ff19 RSP: 002b:00007f0e93bf6058 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007f0e95f45fa0 RCX: 00007f0e95d7ff19 RDX: b635773f06ebbeee RSI: 0000000000b36000 RDI: 0000000020000000 RBP: 00007f0e95df3cc8 R08: ffffffffffffffff R09: 0000000000000000 R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f0e95f45fa0 R15: 00007fffb1aad438 rcu: rcu_preempt kthread starved for 10501 jiffies! g86417 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:27488 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0xe58/0x5ad0 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6848 schedule_timeout+0x124/0x280 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2045 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2247 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 UID: 0 PID: 18186 Comm: kworker/u8:19 Not tainted 6.13.0-rc2-syzkaller-00018-g7cb1b4663150 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline] RIP: 0010:smp_call_function_many_cond+0x458/0x1300 kernel/smp.c:884 Code: 0c 00 85 ed 74 4d 48 b8 00 00 00 00 00 fc ff df 4d 89 f4 4c 89 f5 49 c1 ec 03 83 e5 07 49 01 c4 83 c5 03 e8 aa 0d 0c 00 f3 90 <41> 0f b6 04 24 40 38 c5 7c 08 84 c0 0f 85 a7 0c 00 00 8b 43 08 31 RSP: 0018:ffffc9000c0df998 EFLAGS: 00000293 RAX: 0000000000000000 RBX: ffff8880b8744a40 RCX: ffffffff818df5fc RDX: ffff888012f84880 RSI: ffffffff818df5d6 RDI: 0000000000000005 RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000007 R12: ffffed10170e8949 R13: 0000000000000001 R14: ffff8880b8744a48 R15: ffff8880b863fe40 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c339bde CR3: 000000000df7e000 CR4: 00000000003526f0 DR0: 0000000000000003 DR1: 0000000000000000 DR2: 0000000080000000 DR3: 0000000020000007 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1051 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:2114 [inline] text_poke_bp_batch+0x22b/0x760 arch/x86/kernel/alternative.c:2324 text_poke_flush arch/x86/kernel/alternative.c:2515 [inline] text_poke_flush arch/x86/kernel/alternative.c:2512 [inline] text_poke_finish+0x30/0x40 arch/x86/kernel/alternative.c:2522 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 jump_label_update+0x1d7/0x400 kernel/jump_label.c:920 static_key_enable_cpuslocked+0x1b7/0x270 kernel/jump_label.c:210 static_key_enable+0x1a/0x20 kernel/jump_label.c:223 toggle_allocation_gate mm/kfence/core.c:849 [inline] toggle_allocation_gate+0xfc/0x260 mm/kfence/core.c:841 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3229 process_scheduled_works kernel/workqueue.c:3310 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244