rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P28964/1:b..l P28979/2:b..l P22368/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=165605, q=416 ncpus=2)
task:syz-executor state:R running task stack:21592 pid:22368 tgid:22368 ppid:22352 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x149b/0x4fd0 kernel/sched/core.c:6863
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7190
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:__rcu_read_unlock+0x0/0xe0 kernel/rcu/tree_plugin.h:431
Code: 89 d9 80 e1 07 80 c1 03 38 c1 7c dc 48 89 df e8 56 69 7f 00 eb d2 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 41 57 41 56 41 55 41 54 53 49 bf 00 00 00 00 00 fc ff
RSP: 0018:ffffc9000b4c7230 EFLAGS: 00000286
RAX: a9d6460844105a00 RBX: ffffffff90210901 RCX: 0000000000000046
RDX: 0000000000000001 RSI: ffffffff8d975f94 RDI: ffffffff8bc083e0
RBP: dffffc0000000000 R08: ffffc9000b4c7b30 R09: ffffc9000b4c7358
R10: dffffc0000000000 R11: fffff52001698e6d R12: ffffc9000b4c7b40
R13: ffffc9000b4c0000 R14: ffffc9000b4c7308 R15: ffffffff8173fd65
rcu_read_unlock include/linux/rcupdate.h:899 [inline]
class_rcu_destructor include/linux/rcupdate.h:1195 [inline]
unwind_next_frame+0x1ab6/0x23d0 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
save_stack+0xf5/0x1f0 mm/page_owner.c:165
__reset_page_owner+0x71/0x1f0 mm/page_owner.c:320
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1406 [inline]
free_unref_folios+0xdb3/0x14f0 mm/page_alloc.c:3000
folios_put_refs+0x584/0x670 mm/swap.c:1002
folio_batch_release include/linux/pagevec.h:101 [inline]
shmem_undo_range+0x49e/0x1490 mm/shmem.c:1137
shmem_truncate_range mm/shmem.c:1249 [inline]
shmem_evict_inode+0x26e/0xa70 mm/shmem.c:1379
evict+0x5f4/0xae0 fs/inode.c:837
do_unlinkat+0x340/0x560 fs/namei.c:5443
__do_sys_unlink fs/namei.c:5474 [inline]
__se_sys_unlink fs/namei.c:5472 [inline]
__x64_sys_unlink+0x47/0x50 fs/namei.c:5472
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4d8158ecf7
RSP: 002b:00007ffc0af6a658 EFLAGS: 00000206 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f4d8158ecf7
RDX: 00007ffc0af6a680 RSI: 00007ffc0af6a710 RDI: 00007ffc0af6a710
RBP: 00007ffc0af6a710 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000100 R11: 0000000000000206 R12: 00007ffc0af6b7a0
R13: 00007f4d81613d7d R14: 00000000001f0406 R15: 00007ffc0af6b7e0
task:syz.0.4818 state:R running task stack:25688 pid:28979 tgid:28977 ppid:27231 task_flags:0x400040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x149b/0x4fd0 kernel/sched/core.c:6863
preempt_schedule_irq+0x4d/0xa0 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:lock_release+0x2d8/0x3b0 kernel/locking/lockdep.c:5893
Code: 34 e2 10 00 00 00 00 eb b5 e8 64 6f bb 09 f7 c3 00 02 00 00 74 b9 65 48 8b 05 74 ee e1 10 48 3b 44 24 28 75 44 fb 48 83 c4 30 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 44 1f 72 ff cc 48 8d 3d 11 49 e7
RSP: 0018:ffffc9000b8077c8 EFLAGS: 00000282
RAX: 1638c609b07c4a00 RBX: 0000000000000202 RCX: 0000000000000046
RDX: 0000000000000003 RSI: ffffffff8d975f94 RDI: ffffffff8bc083e0
RBP: ffff88801afd6728 R08: ffffffff82303cc5 R09: ffffffff8df41aa0
R10: dffffc0000000000 R11: fffff94000583389 R12: 0000000000000003
R13: 0000000000000003 R14: ffffffff8df41aa0 R15: ffff88801afd5b80
rcu_lock_release include/linux/rcupdate.h:341 [inline]
rcu_read_unlock include/linux/rcupdate.h:897 [inline]
percpu_ref_tryget_many include/linux/percpu-refcount.h:250 [inline]
percpu_ref_tryget+0xf8/0x180 include/linux/percpu-refcount.h:266
css_tryget include/linux/cgroup_refcnt.h:45 [inline]
get_mem_cgroup_from_mm+0x102/0x2a0 mm/memcontrol.c:941
__mem_cgroup_charge+0x15/0x80 mm/memcontrol.c:4744
mem_cgroup_charge include/linux/memcontrol.h:663 [inline]
shmem_alloc_and_add_folio+0x790/0xf40 mm/shmem.c:1942
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+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fcdef98e1ff
RSP: 002b:00007fcdf08c5df0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000001000000 RCX: 00007fcdef98e1ff
RDX: 0000000001000000 RSI: 00007fcde5600000 RDI: 0000000000000005
RBP: 0000000000000000 R08: 0000000000000000 R09: 000000000000442b
R10: 0000000000000002 R11: 0000000000000293 R12: 0000000000000005
R13: 00007fcdf08c5ef0 R14: 00007fcdf08c5eb0 R15: 00007fcde5600000
task:syz.2.4814 state:R running task stack:26464 pid:28964 tgid:28963 ppid:23385 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x149b/0x4fd0 kernel/sched/core.c:6863
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7190
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:rcu_read_lock include/linux/rcupdate.h:868 [inline]
RIP: 0010:blk_cgroup_congested+0x58/0x210 block/blk-cgroup.c:2237
Code: 31 c0 45 31 c9 53 e8 a7 3f 27 fd 48 83 c4 08 e8 0e e8 e2 06 89 c5 31 ff 89 c6 e8 93 4d 4a fd 85 ed 74 10 e8 0a 4e 30 fd 84 c0 <74> 0e e8 41 49 4a fd eb 56 e8 3a 49 4a fd eb 4f e8 e3 e7 e2 06 89
RSP: 0018:ffffc9000b47f820 EFLAGS: 00000202
RAX: 0000000000000001 RBX: ffffffff8476ae3d RCX: 0000000080000001
RDX: ffff88802df48000 RSI: ffffffff8bc083c0 RDI: ffffffff8bc08380
RBP: 0000000000000001 R08: ffffffff8476ae3d R09: ffffffff8df41aa0
R10: dffffc0000000000 R11: fffffbfff1f0444f R12: ffff8880227ef8c0
R13: dffffc0000000000 R14: ffff88803070ee40 R15: 00007efdc512a000
__folio_throttle_swaprate+0x3c/0x140 mm/swapfile.c:4034
folio_throttle_swaprate include/linux/swap.h:608 [inline]
folio_prealloc+0x10d/0x180 mm/memory.c:1202
alloc_anon_folio mm/memory.c:5165 [inline]
do_anonymous_page mm/memory.c:5222 [inline]
do_pte_missing+0x14e8/0x3330 mm/memory.c:4399
handle_pte_fault mm/memory.c:6273 [inline]
__handle_mm_fault mm/memory.c:6411 [inline]
handle_mm_fault+0x1b26/0x32b0 mm/memory.c:6580
faultin_page mm/gup.c:1126 [inline]
__get_user_pages+0x1650/0x29f0 mm/gup.c:1428
populate_vma_page_range+0x29f/0x3a0 mm/gup.c:1860
__mm_populate+0x24c/0x380 mm/gup.c:1963
mm_populate include/linux/mm.h:3701 [inline]
__do_sys_mlockall mm/mlock.c:769 [inline]
__se_sys_mlockall+0x444/0x500 mm/mlock.c:745
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7efdc478f749
RSP: 002b:00007efdc29f6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000097
RAX: ffffffffffffffda RBX: 00007efdc49e5fa0 RCX: 00007efdc478f749
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001
RBP: 00007efdc4813f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007efdc49e6038 R14: 00007efdc49e5fa0 R15: 00007fffd5fed8d8
rcu: rcu_preempt kthread starved for 10628 jiffies! g165605 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:27480 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x149b/0x4fd0 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+0x510/0xa50 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: 3e b4 b6 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 73 c1 0e 00 f3 0f 1e fa fb f4 13 b4 b6 f5 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90000197e20 EFLAGS: 000002c2
RAX: 000000000268ebbb RBX: ffffffff819713ee RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8d79207b RDI: ffffffff8bc083e0
RBP: ffffc90000197f10 R08: ffff8880b87336db R09: 1ffff110170e66db
R10: dffffc0000000000 R11: ffffed10170e66dc R12: ffffffff8f822270
R13: 1ffff110038d4b70 R14: 0000000000000001 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff888125f1f000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f974b9e0da8 CR3: 000000003ad57000 CR4: 0000000000350ef0
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+0x1be/0x4d0 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