rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P12094/2:b..l P12102/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=60209, q=592 ncpus=2)
task:syz.7.1729 state:R running task stack:22256 pid:12102 tgid:12099 ppid:10097 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x14bc/0x5000 kernel/sched/core.c:6863
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7190
irqentry_exit+0x5d8/0x660 kernel/entry/common.c:216
asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:orc_ip arch/x86/kernel/unwind_orc.c:80 [inline]
RIP: 0010:__orc_find arch/x86/kernel/unwind_orc.c:102 [inline]
RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:227 [inline]
RIP: 0010:unwind_next_frame+0x1315/0x2390 arch/x86/kernel/unwind_orc.c:494
Code: 83 e0 fe 4c 8d 3c 45 00 00 00 00 49 01 ef 4c 89 f8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 0f b6 04 08 84 c0 75 27 49 63 07 <4c> 01 f8 49 8d 4f 04 4c 39 e0 48 0f 46 e9 49 8d 47 fc 48 0f 47 d8
RSP: 0018:ffffc90003567038 EFLAGS: 00000246
RAX: fffffffff2824808 RBX: ffffffff8fa2989c RCX: dffffc0000000000
RDX: ffffffff8fa2982c RSI: ffffffff90225e44 RDI: ffffffff8bc07b80
RBP: ffffffff8fa2982c R08: 000000000000001d R09: ffffffff8df419e0
R10: dffffc0000000000 R11: ffffffff81ad9fb0 R12: ffffffff8224e098
R13: ffffffff8fa2982c R14: ffffc90003567108 R15: ffffffff8fa29864
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
save_stack+0xf5/0x1f0 mm/page_owner.c:165
__set_page_owner+0x8d/0x4c0 mm/page_owner.c:341
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x234/0x290 mm/page_alloc.c:1846
prep_new_page mm/page_alloc.c:1854 [inline]
get_page_from_freelist+0x2365/0x2440 mm/page_alloc.c:3915
__alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5210
alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2486
folio_alloc_mpol_noprof+0x39/0x70 mm/mempolicy.c:2505
shmem_alloc_folio mm/shmem.c:1890 [inline]
shmem_alloc_and_add_folio+0x423/0xf40 mm/shmem.c:1932
shmem_get_folio_gfp+0x59d/0x1660 mm/shmem.c:2556
shmem_get_folio mm/shmem.c:2662 [inline]
shmem_write_begin+0x16c/0x330 mm/shmem.c:3315
generic_perform_write+0x2c5/0x900 mm/filemap.c:4314
shmem_file_write_iter+0xf8/0x120 mm/shmem.c:3490
new_sync_write fs/read_write.c:593 [inline]
vfs_write+0x5c9/0xb30 fs/read_write.c:686
ksys_write+0x145/0x250 fs/read_write.c:738
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: 0033:0x7f2fd0b8e1ff
RSP: 002b:00007f2fd1ad5df0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000001000000 RCX: 00007f2fd0b8e1ff
RDX: 0000000001000000 RSI: 00007f2fc6800000 RDI: 0000000000000007
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000005fa4
R10: 0000200000009082 R11: 0000000000000293 R12: 0000000000000007
R13: 00007f2fd1ad5ef0 R14: 00007f2fd1ad5eb0 R15: 00007f2fc6800000
task:syz.3.1727 state:R running task stack:22608 pid:12094 tgid:12093 ppid:11417 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x14bc/0x5000 kernel/sched/core.c:6863
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7190
irqentry_exit+0x5d8/0x660 kernel/entry/common.c:216
asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:radix_tree_descend lib/radix-tree.c:88 [inline]
RIP: 0010:__radix_tree_lookup lib/radix-tree.c:766 [inline]
RIP: 0010:radix_tree_lookup+0xfc/0x290 lib/radix-tree.c:819
Code: 0f 85 aa 00 00 00 45 0f b6 3c 24 bf 40 00 00 00 44 89 fe e8 46 90 6b f6 41 83 ff 3f 0f 87 a9 00 00 00 e8 37 8d 6b f6 48 89 d8 <44> 89 f9 48 d3 e8 83 e0 3f 4d 8d 3c c4 49 83 c7 28 4c 89 f8 48 c1
RSP: 0018:ffffc900049cf098 EFLAGS: 00000287
RAX: 0000000000000013 RBX: 0000000000000013 RCX: 0000000000080000
RDX: ffffc900104b6000 RSI: 0000000000004c47 RDI: 0000000000004c48
RBP: dffffc0000000000 R08: ffffffff847764d3 R09: ffffffff8df419e0
R10: dffffc0000000000 R11: fffff52000939e4f R12: ffff88803812eec0
R13: 0000000000000fff R14: ffff888050f531b0 R15: 0000000000000006
blkg_lookup block/blk-cgroup.h:268 [inline]
blkg_lookup_create block/blk-cgroup.c:474 [inline]
blkg_tryget_closest block/blk-cgroup.c:2096 [inline]
bio_associate_blkg_from_css+0x476/0xd10 block/blk-cgroup.c:2130
bio_associate_blkg+0x170/0x230 block/blk-cgroup.c:2161
bio_init+0x102/0x2e0 block/bio.c:267
blkdev_issue_flush+0xab/0x110 block/blk-flush.c:472
ext4_sync_fs+0x4f9/0x6c0 fs/ext4/super.c:6420
sync_filesystem+0x1cf/0x230 fs/sync.c:66
try_to_lock_encrypted_files+0x9d/0x670 fs/crypto/keyring.c:1023
do_remove_key+0x3d4/0x580 fs/crypto/keyring.c:1135
__ext4_ioctl fs/ext4/ioctl.c:1833 [inline]
ext4_ioctl+0x1c71/0x4760 fs/ext4/ioctl.c:1917
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
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: 0033:0x7fd9e938f749
RSP: 002b:00007fd9ea17c038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fd9e95e5fa0 RCX: 00007fd9e938f749
RDX: 0000200000000080 RSI: 00000000c0406619 RDI: 0000000000000005
RBP: 00007fd9e9413f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd9e95e6038 R14: 00007fd9e95e5fa0 R15: 00007ffff86ec888
rcu: rcu_preempt kthread starved for 2051 jiffies! g60209 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:26832 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x14bc/0x5000 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6960
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:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
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:check_preemption_disabled+0x12/0x120 lib/smp_processor_id.c:13
Code: 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 41 57 41 56 53 48 83 ec 10 65 48 8b 05 1e f2 22 07 <48> 89 44 24 08 65 8b 05 26 f2 22 07 65 8b 0d 1b f2 22 07 f7 c1 ff
RSP: 0018:ffffc90000a08b40 EFLAGS: 00000082
RAX: 1b84586030ddcf00 RBX: 0000000000000002 RCX: 1b84586030ddcf00
RDX: 0000000000000000 RSI: ffffffff8d976ea8 RDI: ffffffff8bc07be0
RBP: ffff88801c2fe6b0 R08: ffffffff81af6745 R09: ffffffff998de508
R10: 000000000000000b R11: 0000000000010000 R12: 0000000000000000
R13: 0000000000000000 R14: ffffffff998de508 R15: ffff88801c2fdb80
FS: 0000000000000000(0000) GS:ffff888125f3a000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000004a8cc000 CR4: 0000000000350ef0
Call Trace:
lockdep_recursion_finish kernel/locking/lockdep.c:470 [inline]
lock_release+0x26b/0x3b0 kernel/locking/lockdep.c:5891
seqcount_lockdep_reader_access+0xde/0x1c0 include/linux/seqlock.h:73
ktime_get+0x45/0x200 kernel/time/timekeeping.c:824
snd_hrtimer_callback+0x12a/0x3a0 sound/core/hrtimer.c:47
__run_hrtimer kernel/time/hrtimer.c:1777 [inline]
__hrtimer_run_queues+0x51c/0xc30 kernel/time/hrtimer.c:1841
hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1903
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline]
__sysvec_apic_timer_interrupt+0x102/0x3e0 arch/x86/kernel/apic/apic.c:1062
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1056
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: be f3 b4 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 f3 00 0d 00 f3 0f 1e fa fb f4 93 f3 b4 f5 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90000197de0 EFLAGS: 000002c6
RAX: 1b84586030ddcf00 RBX: ffffffff81978eba RCX: 1b84586030ddcf00
RDX: 0000000000000001 RSI: ffffffff8d790585 RDI: ffffffff8bc07be0
RBP: ffffc90000197f10 R08: ffff8880b87336db R09: 1ffff110170e66db
R10: dffffc0000000000 R11: ffffed10170e66dc R12: ffffffff8f81fb70
R13: 1ffff1100385fb70 R14: 0000000000000001 R15: 0000000000000001
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