rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-...!: (1 GPs behind) idle=b9fc/1/0x4000000000000000 softirq=114793/114795 fqs=2
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P14697/1:b..l
rcu: (detected by 1, t=10506 jiffies, g=100541, q=605 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 14698 Comm: syz.9.2175 Not tainted 6.15.0-next-20250604-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:check_wait_context kernel/locking/lockdep.c:4872 [inline]
RIP: 0010:__lock_acquire+0x457/0xd20 kernel/locking/lockdep.c:5190
Code: 8d 4c 24 ff 83 f9 ff bd ff ff ff ff 0f 4c e9 ff c5 45 8d 7c 24 01 49 ff cc 44 89 f9 83 c1 fe 78 44 44 89 e3 81 e3 ff ff ff 7f <83> f9 31 73 1d 48 8d 0c 9b 8b 8c cf 10 0b 00 00 31 c1 41 ff cf 49
RSP: 0018:ffffc90000007b70 EFLAGS: 00000046
RAX: 00000000000c406d RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000002 RSI: 0000000000004000 RDI: ffff888021749e00
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff81ae7462
R10: dffffc0000000000 R11: fffffbfff1f4247f R12: 0000000000000000
R13: 0000000000000002 R14: ffff88802174a918 R15: 0000000000000002
FS: 0000000000000000(0000) GS:ffff888125c4d000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c3cbe5d CR3: 000000000df38000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871
__raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline]
_raw_spin_lock_irq+0xa2/0xf0 kernel/locking/spinlock.c:170
__run_hrtimer kernel/time/hrtimer.c:1765 [inline]
__hrtimer_run_queues+0x602/0xc60 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
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:kasan_check_byte include/linux/kasan.h:399 [inline]
RIP: 0010:lock_acquire+0x85/0x360 kernel/locking/lockdep.c:5845
Code: 71 f1 08 00 84 c0 75 0d f6 05 33 e0 ec 0d 01 0f 84 d7 01 00 00 83 3d 49 20 03 0e 00 0f 84 f0 00 00 00 48 8b b4 24 90 00 00 00 <4c> 89 ef e8 53 78 85 00 83 3d 2c 20 03 0e 00 0f 84 fa 00 00 00 65
RSP: 0018:ffffc900144d7090 EFLAGS: 00000202
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 7a32bd2378ef7b00
RDX: 0000000000000000 RSI: ffffffff81f7a088 RDI: ffffffff8be2a760
RBP: ffffffff81f7a06c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000406 R11: 0000000000000000 R12: 0000000000000002
R13: ffffffff8e13eda0 R14: 0000000000000000 R15: 0000000000000000
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:841 [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+0x38/0x340 include/linux/page_ref.h:264
find_get_entry mm/filemap.c:2050 [inline]
find_lock_entries+0x24f/0xa60 mm/filemap.c:2140
shmem_undo_range+0x254/0x14b0 mm/shmem.c:1107
shmem_truncate_range mm/shmem.c:1237 [inline]
shmem_evict_inode+0x272/0xa70 mm/shmem.c:1365
evict+0x504/0x9c0 fs/inode.c:810
__dentry_kill+0x209/0x660 fs/dcache.c:669
dput+0x19f/0x2b0 fs/dcache.c:911
__fput+0x68e/0xa70 fs/file_table.c:475
task_work_run+0x1d1/0x260 kernel/task_work.c:227
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x6ad/0x22e0 kernel/exit.c:955
do_group_exit+0x21c/0x2d0 kernel/exit.c:1104
get_signal+0x1286/0x1340 kernel/signal.c:3034
arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:111
exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4a5cd8e969
Code: Unable to access opcode bytes at 0x7f4a5cd8e93f.
RSP: 002b:00007f4a5dc4a038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: 0000200000000000 RBX: 00007f4a5cfb5fa0 RCX: 00007f4a5cd8e969
RDX: b635773f06ebbeee RSI: 0000000000b36000 RDI: 0000200000000000
RBP: 00007f4a5ce10ab1 R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f4a5cfb5fa0 R15: 00007ffff7becfd8
task:syz.7.2173 state:R running task stack:25352 pid:14697 tgid:14695 ppid:12509 task_flags:0x40054c flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5396 [inline]
__schedule+0x16f5/0x4d00 kernel/sched/core.c:6785
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7108
irqentry_exit+0x6f/0x90 kernel/entry/common.c:307
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_acquire+0x175/0x360 kernel/locking/lockdep.c:5875
Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 3b fa fe 10 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc90014447238 EFLAGS: 00000206
RAX: bd2d41c512b26f00 RBX: 0000000000000000 RCX: bd2d41c512b26f00
RDX: 0000000000000000 RSI: ffffffff8db70bf6 RDI: ffffffff8be2a7c0
RBP: ffffffff81729de5 R08: 0000000000000000 R09: ffffffff81729de5
R10: ffffc900144473f8 R11: ffffffff81acf940 R12: 0000000000000002
R13: ffffffff8e13eda0 R14: 0000000000000000 R15: 0000000000000246
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:841 [inline]
class_rcu_constructor include/linux/rcupdate.h:1155 [inline]
unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479
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:47 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394
kasan_kmalloc include/linux/kasan.h:260 [inline]
__kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4359
kmalloc_noprof include/linux/slab.h:905 [inline]
slab_free_hook mm/slub.c:2333 [inline]
slab_free mm/slub.c:4643 [inline]
kmem_cache_free+0x166/0x400 mm/slub.c:4745
exit_mmap+0x53f/0xb50 mm/mmap.c:1309
__mmput+0x118/0x420 kernel/fork.c:1121
exit_mm+0x1da/0x2c0 kernel/exit.c:581
do_exit+0x640/0x22e0 kernel/exit.c:943
do_group_exit+0x21c/0x2d0 kernel/exit.c:1104
get_signal+0x1286/0x1340 kernel/signal.c:3034
arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:111
exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8e3858e969
RSP: 002b:00007f8e393b90e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f8e387b5fa8 RCX: 00007f8e3858e969
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f8e387b5fa8
RBP: 00007f8e387b5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f8e387b5fac
R13: 0000000000000000 R14: 00007ffeb7e044e0 R15: 00007ffeb7e045c8
rcu: rcu_preempt kthread starved for 10496 jiffies! g100541 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:27224 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
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+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 12474 Comm: syz-executor Not tainted 6.15.0-next-20250604-syzkaller #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: 0018:ffffc90003e2f560 EFLAGS: 00000293
RAX: ffffffff81b4eab0 RBX: ffff8880b873cb40 RCX: ffff88802a5d9e00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90003e2f6c0 R08: ffffffff8fa123f7 R09: 1ffffffff1f4247e
R10: dffffc0000000000 R11: fffffbfff1f4247f R12: 1ffff110170c86b5
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8880b86435a8
FS: 0000555579901500(0000) GS:ffff888125d4d000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f95076e56c0 CR3: 000000005b666000 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:1361 [inline]
flush_tlb_mm_range+0x6b1/0x12c0 arch/x86/mm/tlb.c:1451
dup_mmap+0x15a0/0x1ac0 mm/mmap.c:1877
dup_mm kernel/fork.c:1477 [inline]
copy_mm+0x13c/0x4b0 kernel/fork.c:1529
copy_process+0x1706/0x3c00 kernel/fork.c:2169
kernel_clone+0x21e/0x870 kernel/fork.c:2599
__do_sys_clone kernel/fork.c:2742 [inline]
__se_sys_clone kernel/fork.c:2726 [inline]
__x64_sys_clone+0x18b/0x1e0 kernel/fork.c:2726
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f95069851d3
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:00007ffedf4cc458 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f95069851d3
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001
R10: 00005555799017d0 R11: 0000000000000246 R12: 0000000000000000
R13: 00000000000927c0 R14: 00000000000e3ba4 R15: 00007ffedf4cc5f0