rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 1-...!: (1 GPs behind) idle=4a34/1/0x4000000000000000 softirq=255957/255959 fqs=0
rcu: (detected by 0, t=10506 jiffies, g=296601, q=415 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 12373 Comm: syz.1.8588 Not tainted 6.15.0-syzkaller-11796-g5abc7438f1e9 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:taprio_set_budgets+0x1/0x3b0 net/sched/sch_taprio.c:659
Code: f7 e8 63 5c 9f f8 e9 0a f8 ff ff 66 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 <41> 57 41 56 41 55 41 54 53 48 83 ec 38 49 89 d7 49 89 f6 48 89 fb
RSP: 0018:ffffc90000a08c60 EFLAGS: 00000046
RAX: 1ffff11008bf03aa RBX: ffff888053c8c2c0 RCX: dffffc0000000000
RDX: ffff888045f81c00 RSI: ffff88804b56fc00 RDI: ffff888053c8c2c0
RBP: ffff888045f81d50 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff5200014117c R12: ffff888053c8c340
R13: ffff888053c8c000 R14: 1845e80538954c00 R15: ffff88804b56fc00
FS: 0000000000000000(0000) GS:ffff888125d5c000(0063) knlGS:00000000f508eb40
CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 00000000801fd018 CR3: 000000007ccba000 CR4: 00000000003526f0
Call Trace:
<IRQ>
advance_sched+0x963/0xc90 net/sched/sch_taprio.c:977
__run_hrtimer kernel/time/hrtimer.c:1761 [inline]
__hrtimer_run_queues+0x52c/0xc60 kernel/time/hrtimer.c:1825
hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1887
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline]
__sysvec_apic_timer_interrupt+0x108/0x410 arch/x86/kernel/apic/apic.c:1056
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1050
</IRQ>
<TASK>
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:sock_recvmsg_nosec+0x28/0x1c0 net/socket.c:1017
Code: 90 90 55 41 57 41 56 41 55 41 54 53 50 89 54 24 04 49 89 f7 49 89 fe 48 bb 00 00 00 00 00 fc ff df e8 8c 32 7f f8 4d 8d 66 20 <4c> 89 e5 48 c1 ed 03 80 7c 1d 00 00 74 08 4c 89 e7 e8 42 a4 e2 f8
RSP: 0018:ffffc9000b0cf840 EFLAGS: 00000246
RAX: ffffffff894129e4 RBX: dffffc0000000000 RCX: 0000000000080000
RDX: ffffc9001682f000 RSI: 000000000007ffff RDI: 0000000000080000
RBP: ffffc9000b0cf9f0 R08: ffffc9000b0cf97f R09: 0000000000000000
R10: ffffc9000b0cf900 R11: fffff52001619f30 R12: ffff888058233020
R13: 1ffff92001619f95 R14: ffff888058233000 R15: ffffc9000b0cfca0
____sys_recvmsg+0x3aa/0x460 net/socket.c:2784
___sys_recvmsg+0x1b5/0x510 net/socket.c:2828
do_recvmmsg+0x36a/0x770 net/socket.c:2915
__sys_recvmmsg+0x19d/0x280 net/socket.c:2997
__do_compat_sys_recvmmsg_time32 net/compat.c:418 [inline]
__se_compat_sys_recvmmsg_time32 net/compat.c:414 [inline]
__ia32_compat_sys_recvmmsg_time32+0xbf/0xe0 net/compat.c:414
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: 0023:0xf709e539
Code: 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 002b:00000000f508e55c EFLAGS: 00000206 ORIG_RAX: 0000000000000151
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000800000c0
RDX: 0000000000010106 RSI: 0000000000000002 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
</TASK>
rcu: rcu_preempt kthread starved for 10506 jiffies! g296601 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:26216 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5396 [inline]
__schedule+0x16f5/0x4d00 kernel/sched/core.c:6785
__schedule_loop kernel/sched/core.c:6863 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6878
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2054
rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2256
kthread+0x711/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 11061 Comm: syz-executor Not tainted 6.15.0-syzkaller-11796-g5abc7438f1e9 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline]
RIP: 0010:smp_call_function_many_cond+0xf69/0x12d0 kernel/smp.c:885
Code: 00 45 8b 2f 44 89 ee 83 e6 01 31 ff e8 60 78 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 0b 74 0b 00 eb 37 f3 90 <43> 0f b6 04 2c 84 c0 75 10 41 f7 07 01 00 00 00 74 1e e8 f0 73 0b
RSP: 0000:ffffc90004a5f720 EFLAGS: 00000293
RAX: ffffffff81b4e880 RBX: ffff8880b863cb40 RCX: ffff888025658000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90004a5f880 R08: ffffffff8fa0f5f7 R09: 1ffffffff1f41ebe
R10: dffffc0000000000 R11: fffffbfff1f41ebf R12: 1ffff110170e828d
R13: dffffc0000000000 R14: 0000000000000001 R15: ffff8880b8741468
FS: 0000000000000000(0000) GS:ffff888125c5c000(0063) knlGS:000000005667f440
CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 000000005668c99c CR3: 0000000032b2e000 CR4: 00000000003526f0
Call Trace:
<TASK>
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1052
__flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline]
flush_tlb_multi arch/x86/mm/tlb.c:1361 [inline]
flush_tlb_mm_range+0x6b1/0x12c0 arch/x86/mm/tlb.c:1451
flush_tlb_page arch/x86/include/asm/tlbflush.h:324 [inline]
ptep_clear_flush+0x120/0x170 mm/pgtable-generic.c:101
wp_page_copy mm/memory.c:3635 [inline]
do_wp_page+0x1bc2/0x5800 mm/memory.c:4030
handle_pte_fault mm/memory.c:6105 [inline]
__handle_mm_fault+0x1144/0x5620 mm/memory.c:6232
handle_mm_fault+0x40a/0x8e0 mm/memory.c:6401
do_user_addr_fault+0xa81/0x1390 arch/x86/mm/fault.c:1336
handle_page_fault arch/x86/mm/fault.c:1476 [inline]
exc_page_fault+0x76/0xf0 arch/x86/mm/fault.c:1532
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0023:0xf71cd156
Code: 24 04 8b 7c 24 10 8d 89 ac 66 00 00 8d 04 3e 39 cd 89 45 38 0f 95 c1 29 fa 0f b6 c9 83 ca 01 c1 e1 02 09 f9 83 c9 01 89 4e 04 <89> 50 04 83 c6 08 8b 54 24 0c 89 f0 e8 a9 c9 ff ff e9 a9 f7 ff ff
RSP: 002b:00000000f755fc60 EFLAGS: 00010206
RAX: 000000005668c998 RBX: 0000000000000000 RCX: 0000000000008021
RDX: 0000000000014669 RSI: 0000000056684978 RDI: 0000000000008020
RBP: 00000000f74096a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
</TASK>