rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P11991/1:b..l P14082/1:b..l P5831/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=67429, q=294 ncpus=2)
task:syz-executor state:R running task stack:21528 pid:5831 tgid:5831 ppid:5821 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x149b/0x4fd0 kernel/sched/core.c:6863
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7190
irqentry_exit+0x5d8/0x660 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:__rcu_read_lock+0x0/0x60 kernel/rcu/tree_plugin.h:413
Code: ff ff 4c 89 ff e8 60 6a 7f 00 e9 3b fb ff ff 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 0f 1e fa 53 65 48 8b 1c 25 08 10 80 92 48 81 c3 84 04 00 00 48
RSP: 0018:ffffc900021bf5e8 EFLAGS: 00000293
RAX: ffffffff81f978d0 RBX: ffffc900021bfac0 RCX: ffff88802c3ddb80
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffea00024f2080
RBP: ffffc900021bf770 R08: ffff88802c3ddb80 R09: 0000000000000003
R10: 0000000000000406 R11: 0000000000000000 R12: ffffea00024f2080
R13: fffffffffffffffe R14: ffffea00024f2080 R15: ffffea00024f2080
rcu_read_lock include/linux/rcupdate.h:865 [inline]
page_ref_add_unless include/linux/page_ref.h:235 [inline]
folio_ref_add_unless include/linux/page_ref.h:248 [inline]
folio_try_get+0x15/0x340 include/linux/page_ref.h:264
find_get_entry mm/filemap.c:2076 [inline]
find_lock_entries+0x24f/0xa60 mm/filemap.c:2166
shmem_undo_range+0x254/0x1490 mm/shmem.c:1119
shmem_truncate_range mm/shmem.c:1249 [inline]
shmem_evict_inode+0x26e/0xa70 mm/shmem.c:1379
evict+0x5f4/0xae0 fs/inode.c:837
do_unlinkat+0x340/0x560 fs/namei.c:5443
__do_sys_unlink fs/namei.c:5474 [inline]
__se_sys_unlink fs/namei.c:5472 [inline]
__x64_sys_unlink+0x47/0x50 fs/namei.c:5472
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5f3a18ecf7
RSP: 002b:00007ffce52bc068 EFLAGS: 00000206 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f5f3a18ecf7
RDX: 00007ffce52bc090 RSI: 00007ffce52bc120 RDI: 00007ffce52bc120
RBP: 00007ffce52bc120 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000100 R11: 0000000000000206 R12: 00007ffce52bd1b0
R13: 00007f5f3a213d7d R14: 00000000000cde38 R15: 00007ffce52bd1f0
task:syz.9.1957 state:R running task stack:26168 pid:14082 tgid:14074 ppid:10649 task_flags:0x400040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x149b/0x4fd0 kernel/sched/core.c:6863
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7190
irqentry_exit+0x5d8/0x660 kernel/entry/common.c:216
asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:debug_lockdep_rcu_enabled+0x0/0x40 kernel/rcu/update.c:319
Code: 48 8d 3d 83 d7 2b 04 48 c7 c6 6d f7 77 8d 67 48 0f b9 3a 90 eb ca cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 31 c0 83 3d 07 8d 28 04 00 74 1e 83 3d 1a bc 28 04 00
RSP: 0018:ffffc9001b3d7410 EFLAGS: 00000286
RAX: 2c425baec8180800 RBX: ffffffff81000130 RCX: 0000000000000046
RDX: 0000000047eca3a8 RSI: ffffffff8d975f94 RDI: ffffffff8bc083e0
RBP: dffffc0000000000 R08: ffffffff8173fd65 R09: ffffffff8df41aa0
R10: dffffc0000000000 R11: ffffffff81acf3d0 R12: 1ffff9200367ae9d
R13: ffffc9001b3d7520 R14: ffffc9001b3d74e8 R15: ffffffff8173fd65
rcu_read_lock include/linux/rcupdate.h:868 [inline]
class_rcu_constructor include/linux/rcupdate.h:1195 [inline]
unwind_next_frame+0xcb/0x23d0 arch/x86/kernel/unwind_orc.c:495
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:253 [inline]
__kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2540 [inline]
slab_free mm/slub.c:6670 [inline]
kmem_cache_free+0x197/0x620 mm/slub.c:6781
tipc_recvstream+0x792/0xe70 net/tipc/socket.c:2088
sock_recvmsg_nosec net/socket.c:1078 [inline]
sock_recvmsg+0x22c/0x270 net/socket.c:1100
____sys_recvmsg+0x1c9/0x460 net/socket.c:2812
___sys_recvmsg+0x1b5/0x510 net/socket.c:2854
__sys_recvmsg net/socket.c:2887 [inline]
__do_sys_recvmsg net/socket.c:2893 [inline]
__se_sys_recvmsg net/socket.c:2890 [inline]
__x64_sys_recvmsg+0x198/0x260 net/socket.c:2890
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f770bf8f749
RSP: 002b:00007f770a1b4038 EFLAGS: 00000246 ORIG_RAX: 000000000000002f
RAX: ffffffffffffffda RBX: 00007f770c1e6180 RCX: 00007f770bf8f749
RDX: 0000000000001f00 RSI: 0000200000000500 RDI: 0000000000000009
RBP: 00007f770c013f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f770c1e6218 R14: 00007f770c1e6180 R15: 00007ffc0bc85138
task:udevd state:R running task stack:23608 pid:11991 tgid:11991 ppid:5192 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x149b/0x4fd0 kernel/sched/core.c:6863
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7190
irqentry_exit+0x5d8/0x660 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:on_stack arch/x86/include/asm/stacktrace.h:58 [inline]
RIP: 0010:stack_access_ok arch/x86/kernel/unwind_orc.c:409 [inline]
RIP: 0010:deref_stack_reg arch/x86/kernel/unwind_orc.c:419 [inline]
RIP: 0010:unwind_next_frame+0xd71/0x23d0 arch/x86/kernel/unwind_orc.c:600
Code: 48 8b 4c 24 20 0f b6 04 01 84 c0 0f 85 58 11 00 00 41 83 3e 00 0f 95 c0 49 39 df 0f 96 c1 20 c1 49 39 dc 0f 97 c0 20 c8 3c 01 <75> 18 48 8d 43 08 4c 39 f8 0f 97 c1 4c 39 e0 0f 96 c0 84 c1 0f 85
RSP: 0018:ffffc9001e47f038 EFLAGS: 00000246
RAX: 0000000000000001 RBX: ffffc9001e47fd18 RCX: 1ffff92003c8fe01
RDX: ffffffff90226b24 RSI: 0000000000000002 RDI: ffffffff8bc08380
RBP: 1ffff92003c8fe22 R08: 0000000000000001 R09: ffffffff8df41aa0
R10: dffffc0000000000 R11: ffffffff81acf3d0 R12: ffffc9001e480000
R13: 1ffff92003c8fe23 R14: ffffc9001e47f108 R15: ffffc9001e478000
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
save_stack+0xf5/0x1f0 mm/page_owner.c:165
__reset_page_owner+0x71/0x1f0 mm/page_owner.c:320
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1406 [inline]
free_unref_folios+0xdb3/0x14f0 mm/page_alloc.c:3000
folios_put_refs+0x584/0x670 mm/swap.c:1002
free_pages_and_swap_cache+0x4be/0x520 mm/swap_state.c:358
__tlb_batch_free_encoded_pages mm/mmu_gather.c:136 [inline]
tlb_batch_pages_flush mm/mmu_gather.c:149 [inline]
tlb_flush_mmu_free mm/mmu_gather.c:397 [inline]
tlb_flush_mmu+0x3a0/0x680 mm/mmu_gather.c:404
tlb_finish_mmu+0xc3/0x1d0 mm/mmu_gather.c:497
vms_clear_ptes+0x42b/0x530 mm/vma.c:1238
vms_complete_munmap_vmas+0x206/0x8a0 mm/vma.c:1280
do_vmi_align_munmap+0x364/0x440 mm/vma.c:1539
do_vmi_munmap+0x253/0x2e0 mm/vma.c:1587
__vm_munmap+0x207/0x380 mm/vma.c:3203
__do_sys_munmap mm/mmap.c:1077 [inline]
__se_sys_munmap mm/mmap.c:1074 [inline]
__x64_sys_munmap+0x60/0x70 mm/mmap.c:1074
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fde3b51e097
RSP: 002b:00007ffecd659e28 EFLAGS: 00000246 ORIG_RAX: 000000000000000b
RAX: ffffffffffffffda RBX: 0000561fe8e41350 RCX: 00007fde3b51e097
RDX: 0000561fe8ebd390 RSI: 0000000000000400 RDI: 00007fde3bb73000
RBP: 000000000000001a R08: 0000561fe8e52e10 R09: 0000000000000003
R10: 0000000000000040 R11: 0000000000000246 R12: 0000561fe8ebd390
R13: 00007fde3bca339c R14: 0000000000043800 R15: 0000000000000009
rcu: rcu_preempt kthread starved for 10638 jiffies! g67429 f0x0 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:27440 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x149b/0x4fd0 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6960
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083
rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: 3e b4 b6 f5 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 73 c1 0e 00 f3 0f 1e fa fb f4 13 b4 b6 f5 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90000197e20 EFLAGS: 000002c2
RAX: 000000000105889f RBX: ffffffff819713ee RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8d79207b RDI: ffffffff8bc083e0
RBP: ffffc90000197f10 R08: ffff8880b87336db R09: 1ffff110170e66db
R10: dffffc0000000000 R11: ffffed10170e66dc R12: ffffffff8f822270
R13: 1ffff110038d1b70 R14: 0000000000000001 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff888125f1f000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4044bff000 CR3: 00000000761ff000 CR4: 0000000000350ef0
Call Trace:
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:767
default_idle_call+0x73/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:191 [inline]
do_idle+0x1be/0x4d0 kernel/sched/idle.c:332
cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:430
start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:312
common_startup_64+0x13e/0x147