rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P24505/1:b..l P24486/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=172777, q=230 ncpus=2)
task:syz.1.6624 state:R running task stack:25104 pid:24486 tgid:24485 ppid:17537 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5249 [inline]
__schedule+0x17e8/0x4a20 kernel/sched/core.c:6597
preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6776
preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6800
preempt_schedule_thunk+0x1a/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:1688 [inline]
zap_pmd_range mm/memory.c:1736 [inline]
zap_pud_range mm/memory.c:1765 [inline]
zap_p4d_range mm/memory.c:1786 [inline]
unmap_page_range+0x3818/0x42c0 mm/memory.c:1807
unmap_vmas+0x3cc/0x5f0 mm/memory.c:1897
exit_mmap+0x264/0xc80 mm/mmap.c:3382
__mmput+0x115/0x390 kernel/fork.c:1346
exit_mm+0x220/0x310 kernel/exit.c:572
do_exit+0x9aa/0x27e0 kernel/exit.c:868
do_group_exit+0x207/0x2c0 kernel/exit.c:1030
get_signal+0x16a1/0x1740 kernel/signal.c:2909
arch_do_signal_or_restart+0x96/0x830 arch/x86/kernel/signal.c:310
exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0xc9/0x370 kernel/entry/common.c:218
do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9c6a575b99
RSP: 002b:00007f9c6b430048 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: 0000000000459faf RBX: 00007f9c6a703fa0 RCX: 00007f9c6a575b99
RDX: 00000000175d9003 RSI: 0000000020000200 RDI: 0000000000000006
RBP: 00007f9c6a5f677e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f9c6a703fa0 R15: 00007ffcf09b9fc8
task:syz-executor state:R running task stack:25584 pid:24505 tgid:24505 ppid:17784 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5249 [inline]
__schedule+0x17e8/0x4a20 kernel/sched/core.c:6597
preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:6919
irqentry_exit+0x5e/0x90 kernel/entry/common.c:354
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_acquire+0x264/0x550 kernel/locking/lockdep.c:5820
Code: 2b 00 74 08 4c 89 f7 e8 7a f1 8a 00 f6 44 24 61 02 0f 85 85 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25
RSP: 0018:ffffc900047c72a0 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 1ffff920008f8e60 RCX: dce40c6f19d5c000
RDX: dffffc0000000000 RSI: ffffffff8bcada80 RDI: ffffffff8c2078e0
RBP: ffffc900047c73e8 R08: ffffffff9300d787 R09: 1ffffffff2601af0
R10: dffffc0000000000 R11: fffffbfff2601af1 R12: 1ffff920008f8e5c
R13: dffffc0000000000 R14: ffffc900047c7300 R15: 0000000000000246
rcu_lock_acquire include/linux/rcupdate.h:333 [inline]
rcu_read_lock include/linux/rcupdate.h:845 [inline]
ext4_get_group_desc+0x133/0x4b0 fs/ext4/balloc.c:288
__ext4_get_inode_loc+0x256/0xee0 fs/ext4/inode.c:4341
ext4_get_inode_loc fs/ext4/inode.c:4490 [inline]
ext4_reserve_inode_write+0x182/0x360 fs/ext4/inode.c:5721
__ext4_mark_inode_dirty+0x1ec/0x880 fs/ext4/inode.c:5898
add_dirent_to_buf+0x5ed/0x750 fs/ext4/namei.c:2167
ext4_add_entry+0x7c6/0x25d0 fs/ext4/namei.c:2399
ext4_add_nondir+0x8d/0x290 fs/ext4/namei.c:2747
ext4_symlink+0x920/0xb50 fs/ext4/namei.c:3385
vfs_symlink+0x137/0x2e0 fs/namei.c:4525
do_symlinkat+0x222/0x3a0 fs/namei.c:4551
__do_sys_symlinkat fs/namei.c:4567 [inline]
__se_sys_symlinkat fs/namei.c:4564 [inline]
__x64_sys_symlinkat+0x95/0xb0 fs/namei.c:4564
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f39f4d751b7
RSP: 002b:00007ffde651a4d8 EFLAGS: 00000202 ORIG_RAX: 000000000000010a
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f39f4d751b7
RDX: 00007f39f4de4a3b RSI: 00000000ffffff9c RDI: 00007f39f4de39db
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000032
R13: 0000000000001388 R14: 00007ffde651a590 R15: 00007ffde651a590
rcu: rcu_preempt kthread starved for 10577 jiffies! g172777 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:26264 pid:17 tgid:17 ppid:2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5249 [inline]
__schedule+0x17e8/0x4a20 kernel/sched/core.c:6597
__schedule_loop kernel/sched/core.c:6674 [inline]
schedule+0x14b/0x320 kernel/sched/core.c:6689
schedule_timeout+0x1be/0x310 kernel/time/timer.c:2581
rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2020
rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2222
kthread+0x2f0/0x390 kernel/kthread.c:389
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:144
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline]
NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:106 [inline]
NMI backtrace for cpu 1 skipped: idling at acpi_safe_halt+0x21/0x30 drivers/acpi/processor_idle.c:112