rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P7661/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=21189, q=503 ncpus=2)
task:syz.4.374 state:R running task stack:25240 pid:7661 tgid:7660 ppid:5837 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5258 [inline]
__schedule+0x150e/0x5070 kernel/sched/core.c:6866
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7193
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:__kasan_check_byte+0x0/0x40 mm/kasan/common.c:572
Code: 00 48 89 df 4c 89 f6 5b 41 5c 41 5e 41 5f e9 c7 fa ff ff 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <0f> 1f 40 d6 41 56 53 48 89 f3 49 89 fe e8 3e 15 00 00 84 c0 75 16
RSP: 0018:ffffc9000e39f3f0 EFLAGS: 00000202
RAX: 0000000000000001 RBX: 0000000000000000 RCX: bb5e1a644dac4f00
RDX: 0000000000000000 RSI: ffffffff81742fa2 RDI: ffffffff8e13f2e0
RBP: ffffffff81742f85 R08: 0000000000000000 R09: 0000000000000000
R10: ffffc9000e39f5b8 R11: ffffffff81ad9d50 R12: 0000000000000002
R13: ffffffff8e13f2e0 R14: 0000000000000000 R15: 0000000000000000
kasan_check_byte include/linux/kasan.h:402 [inline]
lock_acquire+0x84/0x340 kernel/locking/lockdep.c:5842
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:867 [inline]
class_rcu_constructor include/linux/rcupdate.h:1195 [inline]
unwind_next_frame+0xc2/0x23d0 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
unpoison_slab_object mm/kasan/common.c:340 [inline]
__kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4953 [inline]
kmem_cache_alloc_bulk_noprof+0x462/0x720 mm/slub.c:7525
__io_alloc_req_refill+0x9d/0x340 io_uring/io_uring.c:1025
io_alloc_req io_uring/io_uring.h:562 [inline]
io_submit_sqes+0xe58/0x2140 io_uring/io_uring.c:2423
__do_sys_io_uring_enter io_uring/io_uring.c:3280 [inline]
__se_sys_io_uring_enter+0x2e0/0x2b60 io_uring/io_uring.c:3219
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f808a38f749
RSP: 002b:00007f808b1c7038 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa
RAX: ffffffffffffffda RBX: 00007f808a5e5fa0 RCX: 00007f808a38f749
RDX: 00000000000004c1 RSI: 0000000000000627 RDI: 0000000000000005
RBP: 00007f808a413f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000043 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f808a5e6038 R14: 00007f808a5e5fa0 R15: 00007ffc7d034648
rcu: rcu_preempt kthread starved for 10540 jiffies! g21189 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:27552 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5258 [inline]
__schedule+0x150e/0x5070 kernel/sched/core.c:6866
__schedule_loop kernel/sched/core.c:6948 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6963
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+0x599/0xb30 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: 0 UID: 0 PID: 7664 Comm: syz.2.368 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:lock_acquire+0x16c/0x340 kernel/locking/lockdep.c:5872
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 44 41 01 11 <48> 3b 44 24 58 0f 85 e5 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc90003357510 EFLAGS: 00000206
RAX: 519eb3f83e488000 RBX: 0000000000000000 RCX: 519eb3f83e488000
RDX: 0000000093920900 RSI: ffffffff8db7ed49 RDI: ffffffff8be07960
RBP: ffffffff83764103 R08: ffffffff83764103 R09: ffff8880572135f0
R10: dffffc0000000000 R11: fffffbfff1f445ef R12: 0000000000000000
R13: ffff8880572135f0 R14: 0000000000000001 R15: 0000000000000246
FS: 0000000000000000(0000) GS:ffff888125c25000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c2ede49 CR3: 000000002f068000 CR4: 00000000003526f0
Call Trace:
__raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
_raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
spin_lock include/linux/spinlock.h:351 [inline]
xfs_iflags_clear fs/xfs/xfs_inode.h:233 [inline]
xfs_reclaim_inode fs/xfs/xfs_icache.c:1048 [inline]
xfs_icwalk_process_inode fs/xfs/xfs_icache.c:1727 [inline]
xfs_icwalk_ag+0xe63/0x1a90 fs/xfs/xfs_icache.c:1809
xfs_icwalk fs/xfs/xfs_icache.c:1857 [inline]
xfs_reclaim_inodes+0x1c0/0x2b0 fs/xfs/xfs_icache.c:1073
xfs_unmount_flush_inodes+0xc1/0xd0 fs/xfs/xfs_mount.c:626
xfs_unmountfs+0x152/0x320 fs/xfs/xfs_mount.c:1322
xfs_fs_put_super+0x65/0x160 fs/xfs/xfs_super.c:1254
generic_shutdown_super+0x135/0x2c0 fs/super.c:643
kill_block_super+0x44/0x90 fs/super.c:1722
xfs_kill_sb+0x15/0x50 fs/xfs/xfs_super.c:2297
deactivate_locked_super+0xbc/0x130 fs/super.c:474
cleanup_mnt+0x425/0x4c0 fs/namespace.c:1318
task_work_run+0x1d4/0x260 kernel/task_work.c:233
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x8bd/0x25b0 kernel/exit.c:971
do_group_exit+0x21c/0x2d0 kernel/exit.c:1112
get_signal+0x1285/0x1340 kernel/signal.c:3034
arch_do_signal_or_restart+0x9a/0x7a0 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
exit_to_user_mode_loop kernel/entry/common.c:75 [inline]
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:270 [inline]
irqentry_exit_to_user_mode include/linux/irq-entry-common.h:339 [inline]
irqentry_exit+0x177/0x660 kernel/entry/common.c:196
exc_page_fault+0xab/0x100 arch/x86/mm/fault.c:1535
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7f3a4f98f751
Code: Unable to access opcode bytes at 0x7f3a4f98f727.
RSP: 002b:fffffffffffffe70 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007f3a4fbe5fa0 RCX: 00007f3a4f98f749
RDX: 0000000000000000 RSI: fffffffffffffe70 RDI: 0000000000008000
RBP: 00007f3a4fa13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007f3a4fbe6038 R14: 00007f3a4fbe5fa0 R15: 00007ffc989bc278