rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P8859/1:b..l P8877/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=32057, q=1820 ncpus=2)
task:syz.4.654 state:R running task stack:24904 pid:8877 tgid:8861 ppid:5843 task_flags:0x400040 flags:0x00080006
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:lock_release+0x2a6/0x3b0 kernel/locking/lockdep.c:5893
Code: 4d 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f7 44 24 20 00 02 00 00 75 52 f7 c3 00 02 00 00 74 01 fb 65 48 8b 05 2a 0f 01 11 <48> 3b 44 24 28 75 75 48 83 c4 30 5b 41 5c 41 5d 41 5e 41 5f 5d e9
RSP: 0018:ffffc90003c7f4f0 EFLAGS: 00000206
RAX: 9e7eeab069818100 RBX: 0000000000000202 RCX: 9e7eeab069818100
RDX: 0000000000000001 RSI: ffffffff8db7ed49 RDI: ffffffff8be07960
RBP: ffff8880278a8b58 R08: ffffc90003c7fed0 R09: 0000000000000000
R10: ffffc90003c7f678 R11: fffff5200078fed1 R12: 0000000000000001
R13: 0000000000000001 R14: ffffffff8e13f2e0 R15: ffff8880278a8000
rcu_lock_release include/linux/rcupdate.h:341 [inline]
rcu_read_unlock include/linux/rcupdate.h:897 [inline]
class_rcu_destructor include/linux/rcupdate.h:1195 [inline]
unwind_next_frame+0x1ab1/0x23d0 arch/x86/kernel/unwind_orc.c:695
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
poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415
kasan_kmalloc include/linux/kasan.h:263 [inline]
__kmalloc_cache_noprof+0x3e2/0x700 mm/slub.c:5780
kmalloc_noprof include/linux/slab.h:957 [inline]
io_drain_req+0xa6/0x550 io_uring/io_uring.c:1741
io_submit_sqe io_uring/io_uring.c:2315 [inline]
io_submit_sqes+0x13a1/0x2140 io_uring/io_uring.c:2434
__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: 0033:0x7fb1ea38f749
RSP: 002b:00007fb1eb1a8038 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa
RAX: ffffffffffffffda RBX: 00007fb1ea5e6090 RCX: 00007fb1ea38f749
RDX: 0000000000003ec0 RSI: 00000000000047ba RDI: 0000000000000009
RBP: 00007fb1ea413f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000021 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fb1ea5e6128 R14: 00007fb1ea5e6090 R15: 00007fff4b8fa258
task:syz.0.650 state:R running task stack:20608 pid:8859 tgid:8859 ppid:5826 task_flags:0x400640 flags:0x0008000a
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:lockdep_enabled kernel/locking/lockdep.c:121 [inline]
RIP: 0010:lock_is_held_type+0x31/0x190 kernel/locking/lockdep.c:5933
Code: 41 56 41 55 41 54 53 48 83 ec 10 65 48 8b 05 66 fb 41 07 48 89 44 24 08 bb ff ff ff ff 83 3d d5 aa 44 04 00 0f 84 fe 00 00 00 <65> 8b 05 d8 40 42 07 85 c0 0f 85 ef 00 00 00 65 4c 8b 2c 25 08 b0
RSP: 0018:ffffc90003096758 EFLAGS: 00000202
RAX: a555ce3c821eb600 RBX: 00000000ffffffff RCX: ffff8880318a3d00
RDX: 0000000000000000 RSI: 00000000ffffffff RDI: ffff8880294b9c40
RBP: ffff8880294b9c40 R08: ffff8880318a3d00 R09: 0000000000000004
R10: 0000000000000003 R11: 0000000000000000 R12: 0000001b30924000
R13: 0000001b30d23fff R14: 0000000000000300 R15: ffff88807d36f600
lock_is_held include/linux/lockdep.h:249 [inline]
mt_locked lib/maple_tree.c:-1 [inline]
mt_slot lib/maple_tree.c:736 [inline]
mtree_range_walk+0x50f/0x840 lib/maple_tree.c:2579
mas_state_walk lib/maple_tree.c:3298 [inline]
mt_find+0x244/0x5e0 lib/maple_tree.c:6497
find_vma+0xe7/0x160 mm/mmap.c:906
gup_vma_lookup mm/gup.c:1275 [inline]
__get_user_pages+0x3ae/0x29f0 mm/gup.c:1396
__get_user_pages_locked mm/gup.c:1692 [inline]
get_dump_page+0x1ac/0x3f0 mm/gup.c:2192
dump_user_range+0x1de/0xc90 fs/coredump.c:1366
elf_core_dump+0x3369/0x3960 fs/binfmt_elf.c:2111
coredump_write+0x1121/0x18b0 fs/coredump.c:1049
do_coredump fs/coredump.c:1126 [inline]
vfs_coredump+0x3321/0x3e60 fs/coredump.c:1200
get_signal+0x1108/0x1340 kernel/signal.c:3019
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: 0033:0x7fd20b98f751
RSP: 002b:fffffffffffffe70 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007fd20bbe6090 RCX: 00007fd20b98f749
RDX: 0000000000000000 RSI: fffffffffffffe70 RDI: 0000000000008000
RBP: 00007fd20ba13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007fd20bbe6128 R14: 00007fd20bbe6090 R15: 00007ffd56b65278
rcu: rcu_preempt kthread starved for 10510 jiffies! g32057 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: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: 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: cc cc cc cc 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 9e 2a 00 f3 0f 1e fa fb f4 48 ee 02 00 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0000:ffffc90000197de0 EFLAGS: 000002c6
RAX: 213b7a585dd46500 RBX: ffffffff819786ba RCX: 213b7a585dd46500
RDX: 0000000000000001 RSI: ffffffff8d997e54 RDI: ffffffff8be07960
RBP: ffffc90000197f10 R08: ffff8880b87336db R09: 1ffff110170e66db
R10: dffffc0000000000 R11: ffffed10170e66dc R12: ffffffff8fa22f70
R13: 1ffff11003b56b70 R14: 0000000000000001 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff888125d25000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd20c7f6990 CR3: 000000007d362000 CR4: 00000000003526f0
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+0x1ea/0x520 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