rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6497/1:b..l P6541/1:b..l P6523/1:b..l rcu: (detected by 1, t=10503 jiffies, g=19509, q=363 ncpus=2) task:syz.3.207 state:R running task stack:23672 pid:6523 tgid:6523 ppid:5619 task_flags:0x400640 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1295/0x67a0 kernel/sched/core.c:7189 preempt_schedule_common+0x42/0xc0 kernel/sched/core.c:7370 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12 __raw_spin_unlock include/linux/spinlock_api_smp.h:169 [inline] _raw_spin_unlock+0x3e/0x50 kernel/locking/spinlock.c:190 spin_unlock include/linux/spinlock.h:390 [inline] follow_page_pte+0x496/0x13f0 mm/gup.c:889 follow_pmd_mask mm/gup.c:928 [inline] follow_pud_mask mm/gup.c:967 [inline] follow_p4d_mask mm/gup.c:984 [inline] follow_page_mask mm/gup.c:1023 [inline] __get_user_pages+0x741/0x32a0 mm/gup.c:1426 __get_user_pages_locked mm/gup.c:1692 [inline] get_dump_page+0x27e/0x3d0 mm/gup.c:2192 dump_user_range+0x18d/0xad0 fs/coredump.c:1372 elf_core_dump+0x2d5f/0x3d10 fs/binfmt_elf.c:2109 coredump_write fs/coredump.c:1053 [inline] do_coredump fs/coredump.c:1132 [inline] vfs_coredump+0x29a0/0x5770 fs/coredump.c:1206 get_signal+0x2162/0x2210 kernel/signal.c:3022 arch_do_signal_or_restart+0x91/0x7e0 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline] exit_to_user_mode_loop kernel/entry/common.c:98 [inline] __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:252 [inline] irqentry_exit_to_user_mode include/linux/irq-entry-common.h:323 [inline] irqentry_exit+0x410/0x7e0 kernel/entry/common.c:162 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 RIP: 0033:0x7f867659ce61 RSP: 002b:0000000000000030 EFLAGS: 00010217 RAX: 0000000000000000 RBX: 00007f8676815fa0 RCX: 00007f867659ce59 RDX: 0000000000000000 RSI: 0000000000000030 RDI: 0000000000000600 RBP: 00007f8676632d6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007f8676816038 R14: 00007f8676815fa0 R15: 00007ffda35f07e8 task:syz.0.212 state:R running task stack:26248 pid:6541 tgid:6539 ppid:5610 task_flags:0x400140 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1295/0x67a0 kernel/sched/core.c:7189 preempt_schedule_irq+0x50/0x90 kernel/sched/core.c:7513 irqentry_exit_to_kernel_mode_preempt include/linux/irq-entry-common.h:476 [inline] irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:547 [inline] irqentry_exit+0x205/0x7e0 kernel/entry/common.c:164 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:avtab_search_node+0x1f0/0x490 security/selinux/ss/avtab.c:155 Code: 85 92 02 00 00 48 8b 13 48 8d 1c c2 48 b8 00 00 00 00 00 fc ff df 48 89 da 48 c1 ea 03 80 3c 02 00 0f 85 83 02 00 00 48 8b 1b <48> 85 db 0f 84 18 01 00 00 e8 12 24 56 fd 48 8d 7d 06 48 b8 00 00 RSP: 0018:ffffc90007f576f0 EFLAGS: 00000246 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 1ffff1100712a131 RDX: 1ffff11006d70f61 RSI: ffffffff84b27945 RDI: ffffc90007f5787c RBP: ffffc90007f57878 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000800 R11: 0000000000000000 R12: 00000000000002f5 R13: 00000000000007ff R14: 000000000000025b R15: 0000000000000080 cond_compute_av+0x5f/0x350 security/selinux/ss/conditional.c:578 context_struct_compute_av+0x81f/0x1250 security/selinux/ss/services.c:679 security_compute_av+0x5ea/0x11e0 security/selinux/ss/services.c:1177 avc_compute_av+0x84/0x820 security/selinux/avc.c:992 avc_perm_nonode+0xb1/0x180 security/selinux/avc.c:1117 avc_has_perm_noaudit+0x2d4/0x3b0 security/selinux/avc.c:1160 avc_has_perm+0xbd/0x1e0 security/selinux/avc.c:1195 selinux_bpf+0xf4/0x150 security/selinux/hooks.c:7168 security_bpf+0xa5/0x260 security/security.c:5299 __sys_bpf+0x278/0x4b90 kernel/bpf/syscall.c:6224 __do_sys_bpf kernel/bpf/syscall.c:6361 [inline] __se_sys_bpf kernel/bpf/syscall.c:6359 [inline] __x64_sys_bpf+0x7b/0xc0 kernel/bpf/syscall.c:6359 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x10b/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f3ac159ce59 RSP: 002b:00007f3ac245a028 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007f3ac1815fa0 RCX: 00007f3ac159ce59 RDX: 0000000000000094 RSI: 0000200000000200 RDI: 0000000000000005 RBP: 00007f3ac1632d6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f3ac1816038 R14: 00007f3ac1815fa0 R15: 00007ffc2bf306d8 task:syz.3.199 state:R running task stack:23032 pid:6497 tgid:6497 ppid:5619 task_flags:0x40064c flags:0x00080001 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1295/0x67a0 kernel/sched/core.c:7189 preempt_schedule_common+0x42/0xc0 kernel/sched/core.c:7370 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:179 [inline] _raw_spin_unlock_irqrestore+0x61/0x80 kernel/locking/spinlock.c:198 spin_unlock_irqrestore include/linux/spinlock.h:408 [inline] lruvec_unlock_irqrestore include/linux/memcontrol.h:1492 [inline] folios_put_refs+0x4df/0xa90 mm/swap.c:1000 folio_batch_release include/linux/folio_batch.h:101 [inline] shmem_undo_range+0x5e5/0x1570 mm/shmem.c:1149 shmem_truncate_range mm/shmem.c:1277 [inline] shmem_evict_inode+0x3f3/0xc40 mm/shmem.c:1407 evict+0x3c2/0xad0 fs/inode.c:841 iput_final fs/inode.c:1960 [inline] iput.part.0+0x605/0xf50 fs/inode.c:2009 iput+0x35/0x40 fs/inode.c:1975 dentry_unlink_inode+0x2c0/0x4c0 fs/dcache.c:476 __dentry_kill+0x1d0/0x690 fs/dcache.c:718 finish_dput+0x76/0x480 fs/dcache.c:927 dput.part.0+0x456/0x570 fs/dcache.c:976 dput+0x1f/0x30 fs/dcache.c:968 __fput+0x519/0xb50 fs/file_table.c:518 task_work_run+0x150/0x240 kernel/task_work.c:233 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x951/0x2af0 kernel/exit.c:976 do_group_exit+0xd5/0x2a0 kernel/exit.c:1119 get_signal+0x20ff/0x2210 kernel/signal.c:3037 arch_do_signal_or_restart+0x91/0x7e0 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline] exit_to_user_mode_loop kernel/entry/common.c:98 [inline] __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:252 [inline] irqentry_exit_to_user_mode include/linux/irq-entry-common.h:323 [inline] irqentry_exit+0x410/0x7e0 kernel/entry/common.c:162 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 RIP: 0033:0x7f867659ce61 RSP: 002b:fffffffffffffe70 EFLAGS: 00010217 RAX: 0000000000000000 RBX: 00007f8676815fa0 RCX: 00007f867659ce59 RDX: 0000000000000000 RSI: fffffffffffffe70 RDI: 0000000000008000 RBP: 00007f8676632d6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007f8676816038 R14: 00007f8676815fa0 R15: 00007ffda35f07e8 rcu: rcu_preempt kthread starved for 10260 jiffies! g19509 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:28904 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1295/0x67a0 kernel/sched/core.c:7189 __schedule_loop kernel/sched/core.c:7268 [inline] schedule+0xdd/0x390 kernel/sched/core.c:7283 schedule_timeout+0x127/0x280 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1a9/0x900 kernel/rcu/tree.c:2095 rcu_gp_kthread+0x179/0x230 kernel/rcu/tree.c:2297 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 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 04/18/2026 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:63 Code: c6 92 02 e9 c3 42 03 00 0f 1f 00 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 e3 e1 20 00 fb f4 cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 RSP: 0018:ffffc90000197df0 EFLAGS: 00000246 RAX: 00000000002d81f3 RBX: ffff88801e2ba500 RCX: ffffffff8b8ab095 RDX: 0000000000000000 RSI: ffffffff8df21e54 RDI: ffffffff8c1c3880 RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed10170a67b5 R10: ffff8880b8533dab R11: 0000000000000000 R12: 0000000000000001 R13: ffffed1003c574a0 R14: 0000000000000001 R15: ffffffff90d7c250 FS: 0000000000000000(0000) GS:ffff888124470000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000020000001f030 CR3: 0000000065782000 CR4: 00000000003526f0 Call Trace: arch_safe_halt arch/x86/include/asm/paravirt.h:62 [inline] default_idle+0x9/0x10 arch/x86/kernel/process.c:767 default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:199 [inline] do_idle+0x464/0x590 kernel/sched/idle.c:352 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:451 start_secondary+0x21d/0x2d0 arch/x86/kernel/smpboot.c:312 common_startup_64+0x13e/0x148