rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 1-...!: (1 GPs behind) idle=46a4/1/0x4000000000000000 softirq=31519/31521 fqs=3
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P8107/1:b..l P6270/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=25517, q=377 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 6730 Comm: syz-executor Not tainted 6.15.0-rc1-next-20250408-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:check_preemption_disabled+0x4e/0x120 lib/smp_processor_id.c:55
Code: 07 65 8b 05 f4 2e 37 07 a9 ff ff ff 7f 74 24 65 49 8b 04 24 48 3b 44 24 08 0f 85 cc 00 00 00 89 d8 48 83 c4 10 5b 41 5c 41 5d <41> 5e 41 5f c3 cc cc cc cc 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7
RSP: 0018:ffffc90000a08c10 EFLAGS: 00000082
RAX: 0000000000000001 RBX: 00000000ffffffff RCX: ffff88802dc30000
RDX: ffff88802dc30000 RSI: ffffffff8e773b35 RDI: ffffffff8ca1e500
RBP: ffffffff93697020 R08: ffffffff8a28757b R09: fffff5200014117c
R10: dffffc0000000000 R11: fffff5200014117c R12: ffff88802dc30000
R13: 0000000000000046 R14: 00000000ffffffff R15: ffff88805cedb300
FS: 0000555567bc8500(0000) GS:ffff888125089000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f3dda2d56c0 CR3: 000000007cb5a000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
lockdep_recursion_inc kernel/locking/lockdep.c:467 [inline]
lock_is_held_type+0x7f/0x1a0 kernel/locking/lockdep.c:5937
lock_is_held include/linux/lockdep.h:249 [inline]
advance_sched+0x1c2/0xca0 net/sched/sch_taprio.c:929
__run_hrtimer kernel/time/hrtimer.c:1761 [inline]
__hrtimer_run_queues+0x5a6/0xd40 kernel/time/hrtimer.c:1825
hrtimer_interrupt+0x403/0xa40 kernel/time/hrtimer.c:1887
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline]
__sysvec_apic_timer_interrupt+0x110/0x420 arch/x86/kernel/apic/apic.c:1055
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1049
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x0/0x90 kernel/kcov.c:313
Code: 10 48 89 74 0a 18 4c 89 44 0a 20 c3 cc cc cc cc 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 0f 1e fa 4c 8b 04 24 65 48 8b 14 25 08 70 69 93 65 8b 05 d8 26
RSP: 0018:ffffc9000381f2d8 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff88802dc30000
RDX: 0000000000000000 RSI: 000000000000007a RDI: 0000000000000001
RBP: ffffc9000381f610 R08: ffffffff8213d82b R09: 1ffffd400029bba0
R10: dffffc0000000000 R11: fffff9400029bba1 R12: ffffea00014ddd00
R13: 1ffff92000703e94 R14: 000000000000007a R15: ffff888042505de0
constant_test_bit arch/x86/include/asm/bitops.h:-1 [inline]
arch_test_bit arch/x86/include/asm/bitops.h:238 [inline]
_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:142 [inline]
folio_test_head include/linux/page-flags.h:860 [inline]
folio_test_large include/linux/page-flags.h:881 [inline]
copy_present_ptes mm/memory.c:1002 [inline]
copy_pte_range+0x788/0x6680 mm/memory.c:1176
copy_pmd_range mm/memory.c:1264 [inline]
copy_pud_range mm/memory.c:1301 [inline]
copy_p4d_range mm/memory.c:1325 [inline]
copy_page_range+0xe57/0x13a0 mm/memory.c:1419
dup_mmap kernel/fork.c:726 [inline]
dup_mm kernel/fork.c:1734 [inline]
copy_mm+0x130d/0x22c0 kernel/fork.c:1786
copy_process+0x17de/0x3d10 kernel/fork.c:2446
kernel_clone+0x242/0x930 kernel/fork.c:2861
__do_sys_clone kernel/fork.c:3004 [inline]
__se_sys_clone kernel/fork.c:2988 [inline]
__x64_sys_clone+0x268/0x2e0 kernel/fork.c:2988
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3dd95839d3
Code: 1f 84 00 00 00 00 00 64 48 8b 04 25 10 00 00 00 45 31 c0 31 d2 31 f6 bf 11 00 20 01 4c 8d 90 d0 02 00 00 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 89 c2 85 c0 75 2c 64 48 8b 04 25 10 00 00
RSP: 002b:00007ffd3808edf8 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f3dd95839d3
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001
R10: 0000555567bc87d0 R11: 0000000000000246 R12: 0000000000000000
R13: 00000000000927c0 R14: 00000000000304fb R15: 00007ffd3808ef90
task:udevd state:R running task stack:23176 pid:6270 tgid:6270 ppid:5203 task_flags:0x400140 flags:0x00000002
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x1b88/0x5240 kernel/sched/core.c:6767
preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6947
preempt_schedule+0xe4/0xf0 kernel/sched/core.c:6971
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
_raw_spin_unlock_irqrestore+0x134/0x140 kernel/locking/spinlock.c:194
spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
__wake_up_common_lock+0x18c/0x1e0 kernel/sched/wait.c:108
sock_def_readable+0x20f/0x5a0 net/core/sock.c:3528
unix_dgram_sendmsg+0xf59/0x1ea0 net/unix/af_unix.c:2154
sock_sendmsg_nosec net/socket.c:712 [inline]
__sock_sendmsg+0x221/0x270 net/socket.c:727
sock_write_iter+0x2d9/0x3f0 net/socket.c:1131
new_sync_write fs/read_write.c:591 [inline]
vfs_write+0x70f/0xd10 fs/read_write.c:684
ksys_write+0x19d/0x2d0 fs/read_write.c:736
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3f9ff16bf2
RSP: 002b:00007fff3ba2c058 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f3f9ff16bf2
RDX: 0000000000000000 RSI: 00007fff3ba2c0af RDI: 000000000000000a
RBP: 00007fff3ba2c0af R08: 0000000000000001 R09: 0000000000000000
R10: 000000000000010f R11: 0000000000000246 R12: 000000000000000a
R13: 00007f3fa02cdae0 R14: 0000000000000000 R15: 000055804061f910
task:syz.4.649 state:R running task stack:24936 pid:8107 tgid:8107 ppid:5831 task_flags:0x40004c flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x1b88/0x5240 kernel/sched/core.c:6767
preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6947
preempt_schedule+0xe4/0xf0 kernel/sched/core.c:6971
preempt_schedule_thunk+0x16/0x30 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]
zap_pte_range mm/memory.c:1770 [inline]
zap_pmd_range mm/memory.c:1832 [inline]
zap_pud_range mm/memory.c:1861 [inline]
zap_p4d_range mm/memory.c:1882 [inline]
unmap_page_range+0x39c5/0x44d0 mm/memory.c:1903
unmap_vmas+0x3ce/0x5f0 mm/memory.c:1993
exit_mmap+0x2bc/0xde0 mm/mmap.c:1284
__mmput+0x115/0x420 kernel/fork.c:1379
exit_mm+0x221/0x310 kernel/exit.c:575
do_exit+0x6e8/0x2520 kernel/exit.c:937
do_group_exit+0x207/0x2c0 kernel/exit.c:1098
__do_sys_exit_group kernel/exit.c:1109 [inline]
__se_sys_exit_group kernel/exit.c:1107 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1107
x64_sys_call+0x26c3/0x26d0 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f04d118d169
RSP: 002b:00007fffea9d2058 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f04d118d169
RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fffea9d20bc R08: 00000004ea9d214f R09: 00000000000927c0
R10: 000000000000186c R11: 0000000000000246 R12: 00000000000000a8
R13: 00000000000927c0 R14: 00000000000300f4 R15: 00007fffea9d2110
rcu: rcu_preempt kthread starved for 10496 jiffies! g25517 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:26976 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x1b88/0x5240 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0x163/0x360 kernel/sched/core.c:6860
schedule_timeout+0x15b/0x2b0 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x2e1/0x1340 kernel/rcu/tree.c:2046
rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2248
kthread+0x7b7/0x940 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 8094 Comm: syz.3.642 Not tainted 6.15.0-rc1-next-20250408-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline]
RIP: 0010:smp_call_function_many_cond+0x1bac/0x2d40 kernel/smp.c:885
Code: 03 84 c0 75 7e 45 8b 65 00 44 89 e6 83 e6 01 31 ff e8 88 e7 0b 00 41 83 e4 01 4c 8b 64 24 68 75 07 e8 38 e3 0b 00 eb 41 f3 90 <48> b8 00 00 00 00 00 fc ff df 0f b6 04 03 84 c0 75 11 41 f7 45 00
RSP: 0018:ffffc9000b507620 EFLAGS: 00000293
RAX: ffffffff81b761ed RBX: 1ffff110170e7e91 RCX: ffff88807f6c3c00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000b507820 R08: ffffffff81b761b8 R09: 1ffffffff20c01c6
R10: dffffc0000000000 R11: fffffbfff20c01c7 R12: ffff8880b863ad08
R13: ffff8880b873f488 R14: ffff8880b863ad00 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff888124f89000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b30509ff8 CR3: 000000007f3b6000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
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:1280 [inline]
flush_tlb_mm_range+0xb8d/0x13f0 arch/x86/mm/tlb.c:1370
tlb_flush arch/x86/include/asm/tlb.h:23 [inline]
tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:480 [inline]
tlb_flush_mmu+0x1aa/0x690 mm/mmu_gather.c:403
tlb_finish_mmu+0xd4/0x200 mm/mmu_gather.c:496
exit_mmap+0x5b1/0xde0 mm/mmap.c:1297
__mmput+0x115/0x420 kernel/fork.c:1379
exit_mm+0x221/0x310 kernel/exit.c:575
do_exit+0x6e8/0x2520 kernel/exit.c:937
do_group_exit+0x207/0x2c0 kernel/exit.c:1098
__do_sys_exit_group kernel/exit.c:1109 [inline]
__se_sys_exit_group kernel/exit.c:1107 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1107
x64_sys_call+0x26c3/0x26d0 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2b86f8d169
Code: Unable to access opcode bytes at 0x7f2b86f8d13f.
RSP: 002b:00007ffdd5f0e9e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f2b86f8d169
RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffdd5f0ea4c R08: 00000004d5f0eadf R09: 00000000000927c0
R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000091
R13: 00000000000927c0 R14: 000000000002ff2b R15: 00007ffdd5f0eaa0