rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P25322/4:b..l P25304/3:b..l P25317/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=103941, q=1977 ncpus=2)
task:syz.1.5031 state:R running task stack:28776 pid:25317 tgid:25316 ppid:24493 task_flags:0x400040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x1553/0x5240 kernel/sched/core.c:6911
preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7095
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:179 [inline]
_raw_spin_unlock_irqrestore+0x74/0x80 kernel/locking/spinlock.c:194
task_rq_unlock kernel/sched/sched.h:1917 [inline]
sched_core_update_cookie kernel/sched/core_sched.c:96 [inline]
__sched_core_set+0x27c/0x400 kernel/sched/core_sched.c:126
sched_core_share_pid+0x511/0x7b0 kernel/sched/core_sched.c:228
__do_sys_prctl kernel/sys.c:2807 [inline]
__se_sys_prctl+0x884/0x1a60 kernel/sys.c:2533
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa3c9ddc819
RSP: 002b:00007fa3c8036028 EFLAGS: 00000246 ORIG_RAX: 000000000000009d
RAX: ffffffffffffffda RBX: 00007fa3ca055fa0 RCX: 00007fa3c9ddc819
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 000000000000003e
RBP: 00007fa3c9e72c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa3ca056038 R14: 00007fa3ca055fa0 R15: 00007ffec2d7bde8
task:syz.8.5027 state:R running task stack:26408 pid:25304 tgid:25303 ppid:14336 task_flags:0x40054c flags:0x00080001
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x1553/0x5240 kernel/sched/core.c:6911
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7238
irqentry_exit+0x599/0x620 kernel/entry/common.c:239
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x20b/0x2e0 kernel/locking/lockdep.c:5872
Code: e9 30 ff ff ff e8 55 1d 84 09 f7 c3 00 02 00 00 0f 84 38 ff ff ff 65 48 8b 05 c1 aa ae 10 48 3b 44 24 30 75 33 fb 48 83 c4 38 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 48 8d 3d de 63 cd
RSP: 0000:ffffc9000e107310 EFLAGS: 00000292
RAX: fd0999e01dd6d200 RBX: 0000000000000246 RCX: 0000000000000046
RDX: 00000000c8b490ac RSI: ffffffff8d7c20a5 RDI: ffffffff8ba67a80
RBP: 0000000000000000 R08: ffffffff82320594 R09: ffffffff8ddcb980
R10: dffffc0000000000 R11: fffff940004ed1b1 R12: 0000000000000002
R13: ffffffff8ddcb980 R14: 0000000000000000 R15: 0000000000000000
rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
rcu_read_lock include/linux/rcupdate.h:850 [inline]
page_table_check_clear+0x164/0x5f0 mm/page_table_check.c:77
ptep_get_and_clear_full arch/x86/include/asm/jump_label.h:-1 [inline]
get_and_clear_full_ptes include/linux/pgtable.h:846 [inline]
zap_present_folio_ptes mm/memory.c:1643 [inline]
zap_present_ptes mm/memory.c:1725 [inline]
do_zap_pte_range mm/memory.c:1827 [inline]
zap_pte_range mm/memory.c:1929 [inline]
zap_pmd_range mm/memory.c:2021 [inline]
zap_pud_range mm/memory.c:2049 [inline]
zap_p4d_range mm/memory.c:2070 [inline]
unmap_page_range+0x3015/0x4540 mm/memory.c:2091
unmap_single_vma mm/memory.c:2133 [inline]
unmap_vmas+0x48f/0x6a0 mm/memory.c:2171
exit_mmap+0x280/0xa10 mm/mmap.c:1302
__mmput+0xcb/0x3d0 kernel/fork.c:1175
exit_mm+0x168/0x220 kernel/exit.c:581
do_exit+0x6a2/0x23c0 kernel/exit.c:964
do_group_exit+0x21b/0x2d0 kernel/exit.c:1118
get_signal+0x125c/0x1310 kernel/signal.c:3034
arch_do_signal_or_restart+0xbc/0x830 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
exit_to_user_mode_loop+0x86/0x480 kernel/entry/common.c:98
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline]
do_syscall_64+0x32d/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f94d072c819
RSP: 002b:00007f94ce986028 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: fffffffffffffe00 RBX: 00007f94d09a5fa0 RCX: 00007f94d072c819
RDX: 0000000000000003 RSI: 0000200000001240 RDI: 0000000000000003
RBP: 00007f94d07c2c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000002090 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f94d09a6038 R14: 00007f94d09a5fa0 R15: 00007ffc3d186a78
task:syz.9.5032 state:R running task stack:28096 pid:25322 tgid:25321 ppid:23384 task_flags:0x400040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x1553/0x5240 kernel/sched/core.c:6911
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7238
irqentry_exit+0x599/0x620 kernel/entry/common.c:239
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x80 kernel/kcov.c:210
Code: 89 fb e8 23 00 00 00 48 8b 3d e4 0d bc 0b 48 89 de 5b e9 53 a2 5a 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 48 8b 04 24 65 48 8b 0d 08 5e 8a 10 65 8b 35 29 5e 8a
RSP: 0000:ffffc9000dfd7980 EFLAGS: 00000246
RAX: ffffffff81ff8561 RBX: ffffea0001056300 RCX: ffff88802d0e0000
RDX: 0000000000000002 RSI: 0000000000000000 RDI: 0000000000000002
RBP: ffffc9000dfd7b00 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffff9400020ac61 R12: 1ffffd400020ac61
R13: 008000000000412d R14: 0000000000000000 R15: dffffc0000000000
folio_unlock+0x101/0x160 mm/filemap.c:1510
filemap_map_pages+0x1196/0x1c50 mm/filemap.c:3938
do_fault_around mm/memory.c:5757 [inline]
do_read_fault mm/memory.c:5790 [inline]
do_fault mm/memory.c:5933 [inline]
do_pte_missing+0x16b6/0x29e0 mm/memory.c:4477
handle_pte_fault mm/memory.c:6317 [inline]
__handle_mm_fault mm/memory.c:6455 [inline]
handle_mm_fault+0xd0a/0x13c0 mm/memory.c:6624
do_user_addr_fault+0xa73/0x1340 arch/x86/mm/fault.c:1334
handle_page_fault arch/x86/mm/fault.c:1474 [inline]
exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1527
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7fe669225980
RSP: 002b:00007fe66748bf58 EFLAGS: 00010202
RAX: 000000000000000b RBX: 0000000000000003 RCX: 0000000000000000
RDX: 0000000000000080 RSI: 00007fe66748bfa0 RDI: 00007fe66748d050
RBP: 00007fe66748cfd0 R08: 0000000000000001 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000000 R12: 00007fe66748bfa0
R13: 0000200000000080 R14: 0000000000000006 R15: 0000000000000000
rcu: rcu_preempt kthread starved for 308 jiffies! g103941 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:27728 pid:18 tgid:18 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x1553/0x5240 kernel/sched/core.c:6911
__schedule_loop kernel/sched/core.c:6993 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7008
schedule_timeout+0x158/0x2c0 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x312/0x11d0 kernel/rcu/tree.c:2095
rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2297
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
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: 25320 Comm: syz.1.5031 Tainted: G L syzkaller #0 PREEMPT_{RT,(full)}
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:179 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x47/0x80 kernel/locking/spinlock.c:194
Code: f7 e8 3d 1a 79 f6 f7 c3 00 02 00 00 74 05 e8 f0 96 a4 f6 9c 58 a9 00 02 00 00 75 27 f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 d4 e4 6b f6 65 8b 05 dd 09 27 07 85 c0 74 18 5b 41 5e e9 41 3c
RSP: 0018:ffffc9000e0677e8 EFLAGS: 00000206
RAX: 0000000000000002 RBX: 0000000000000246 RCX: 0000000080000001
RDX: 0000000000000006 RSI: ffffffff8d566027 RDI: 0000000000000001
RBP: ffffc9000e0678f0 R08: ffffffff8f6a77b7 R09: 1ffffffff1ed4ef6
R10: dffffc0000000000 R11: fffffbfff1ed4ef7 R12: dffffc0000000000
R13: 1ffff92001c0cf08 R14: ffff88805dad4e40 R15: ffff88805dad4e40
FS: 00007fa3c80156c0(0000) GS:ffff888126332000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f65f70beab7 CR3: 000000003d6cc000 CR4: 00000000003526f0
Call Trace:
unlock_rt_mutex_safe kernel/locking/rtmutex.c:344 [inline]
rt_mutex_slowunlock+0x4a7/0x8b0 kernel/locking/rtmutex.c:1454
unix_stream_data_wait net/unix/af_unix.c:2704 [inline]
unix_stream_read_generic+0x1953/0x23a0 net/unix/af_unix.c:2981
unix_stream_recvmsg+0x16e/0x1d0 net/unix/af_unix.c:3146
sock_recvmsg_nosec net/socket.c:1078 [inline]
sock_recvmsg+0x172/0x1b0 net/socket.c:1100
__sys_recvfrom+0x23f/0x3d0 net/socket.c:2256
__do_sys_recvfrom net/socket.c:2271 [inline]
__se_sys_recvfrom net/socket.c:2267 [inline]
__x64_sys_recvfrom+0xde/0x100 net/socket.c:2267
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa3c9ddc819
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fa3c8015028 EFLAGS: 00000246 ORIG_RAX: 000000000000002d
RAX: ffffffffffffffda RBX: 00007fa3ca056090 RCX: 00007fa3c9ddc819
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000005
RBP: 00007fa3c9e72c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000010102 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa3ca056128 R14: 00007fa3ca056090 R15: 00007ffec2d7bde8