rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-...!: (9258 ticks this GP) idle=1d14/1/0x4000000000000000 softirq=23492/23493 fqs=485
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1):
P6843/1:b..l
P5625/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=21589, q=1029 ncpus=2)
task:syz-executor state:R
running task stack:22352 pid:5625 tgid:5625 ppid:5614 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5504 [inline]
__schedule+0x17d9/0x56c0 kernel/sched/core.c:7228
preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7409
preempt_schedule_thunk+0x16/0x40 arch/x86/entry/thunk.S:12
__raw_spin_unlock include/linux/spinlock_api_smp.h:169 [inline]
_raw_spin_unlock+0x3f/0x50 kernel/locking/spinlock.c:190
spin_unlock include/linux/spinlock.h:390 [inline]
wp_page_copy mm/memory.c:3976 [inline]
do_wp_page+0x3ec0/0x4c70 mm/memory.c:4336
handle_pte_fault mm/memory.c:6395 [inline]
__handle_mm_fault mm/memory.c:6517 [inline]
handle_mm_fault+0x1490/0x3080 mm/memory.c:6686
do_user_addr_fault+0xa4d/0x1340 arch/x86/mm/fault.c:1343
handle_page_fault arch/x86/mm/fault.c:1483 [inline]
exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1536
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595
RIP: 0033:0x7fd5975c591e
RSP: 002b:00007ffea95f20d0 EFLAGS: 00010202
RAX: 0000000000000083 RBX: 00007ffea95f20d0 RCX: 00007fd5975c58d2
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00007ffea95f20d0
RBP: 0000000000000083 R08: 0000000000000000 R09: 0000000000000001
R10: 00005555828077d0 R11: 0000000000000246 R12: 0000000000000001
R13: 00000000000927c0 R14: 0000000000025de6 R15: 00007ffea95f22b0
task:syz.1.245 state:R
running task stack:25848 pid:6843 tgid:6822 ppid:5629 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5504 [inline]
__schedule+0x17d9/0x56c0 kernel/sched/core.c:7228
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7552
irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline]
irqentry_exit+0x14f/0x8f0 kernel/entry/common.c:167
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline]
RIP: 0010:rcu_is_watching+0x69/0xb0 kernel/rcu/tree.c:752
Code: e8 fc b5 88 00 48 c7 c3 d8 68 40 93 49 03 1e 48 89 d8 48 c1 e8 03 42 0f b6 04 38 84 c0 75 34 8b 03 65 ff 0d 69 23 94 11 74 11 <83> e0 04 c1 e8 02 5b 41 5e 41 5f e9 32 34 65 ff cc e8 61 62 88 ff
RSP: 0018:ffffc90004e9f820 EFLAGS: 00000286
RAX: 000000000031b914 RBX: ffff8880b87338d8 RCX: 0000000080000001
RDX: 0000000000000000 RSI: ffffffff8c2a8c60 RDI: ffffffff8c2a8c20
RBP: ffffffff8205371d R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffff520009d3f2b R12: 0000000000000002
R13: ffffffff8e959be0 R14: ffffffff8e29d7d8 R15: dffffc0000000000
trace_lock_acquire include/trace/events/lock.h:23 [inline]
lock_acquire+0x5f/0x350 kernel/locking/lockdep.c:5831
rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
rcu_read_lock include/linux/rcupdate.h:840 [inline]
filemap_get_entry+0xe9/0x3f0 mm/filemap.c:1899
shmem_get_folio_gfp+0x26f/0x16d0 mm/shmem.c:2426
shmem_get_folio mm/shmem.c:2608 [inline]
shmem_write_begin+0x16c/0x330 mm/shmem.c:3239
generic_perform_write+0x2d5/0x8f0 mm/filemap.c:4363
shmem_file_write_iter+0xf8/0x120 mm/shmem.c:3414
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x612/0xba0 fs/read_write.c:687
ksys_write+0x150/0x270 fs/read_write.c:739
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5ca9d5d68e
RSP: 002b:00007f5ca7fd4da8 EFLAGS: 00000246
ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f5ca7fd56c0 RCX: 00007f5ca9d5d68e
RDX: 0000000001000000 RSI: 00007f5c9fa00000 RDI: 0000000000000007
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000007
R13: 00007f5ca7fd4ee0 R14: 00007f5ca7fd4ea0 R15: 00007f5c9fa00000
rcu: rcu_preempt kthread starved for 9535 jiffies! g21589 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:28488 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5504 [inline]
__schedule+0x17d9/0x56c0 kernel/sched/core.c:7228
__schedule_loop kernel/sched/core.c:7307 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7322
schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x30c/0x11f0 kernel/rcu/tree.c:2123
rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2325
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 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: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:64
Code: 5c 77 02 e9 fe bf 5d 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 33 e8 16 00 fb f4 d7 bf 5d f5 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90
RSP: 0018:ffffc90000197e40 EFLAGS: 00000246
RAX: ffff88812532d000 RBX: ffffffff819a71cc RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8c2a8c60 RDI: ffffffff819a71cc
RBP: ffffc90000197f10 R08: ffff8880b87338db R09: 1ffff110170e671b
R10: dffffc0000000000 R11: ffffed10170e671c R12: 0000000000000000
R13: 1ffff11003b56000 R14: 1ffff92000032fd0 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff88812532d000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f63c1f546d6 CR3: 000000007ee58000 CR4: 0000000000350ef0
Call Trace:
arch_safe_halt arch/x86/kernel/process.c:766 [inline]
default_idle+0x9/0x20 arch/x86/kernel/process.c:767
default_idle_call+0x72/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:199 [inline]
do_idle+0x1cc/0x540 kernel/sched/idle.c:355
cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:454
start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:312
common_startup_64+0x13e/0x157