rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P17356/1:b..l
rcu: (detected by 0, t=10503 jiffies, g=76133, q=381 ncpus=2)
task:syz.2.3901 state:R running task stack:25608 pid:17356 tgid:17355 ppid:10305 task_flags:0x400040 flags:0x00080001
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7256
irqentry_exit+0x6f/0x90 kernel/entry/common.c:211
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:get_current arch/x86/include/asm/current.h:25 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x8/0x70 kernel/kcov.c:216
Code: 8b 3d 24 c2 d2 0b 48 89 de 5b e9 53 86 5a 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 04 24 <65> 48 8b 0c 25 08 20 6e 92 65 8b 15 28 1c ae 10 81 e2 00 01 ff 00
RSP: 0018:ffffc9000d22f830 EFLAGS: 00000246
RAX: ffffffff8b43b0ac RBX: ffffc9000d22f920 RCX: 0000000000080000
RDX: ffffc9000c181000 RSI: 000000000007ffff RDI: ffffc9000d22f920
RBP: dffffc0000000000 R08: 0000000000000000 R09: ffffffff81f8366d
R10: dffffc0000000000 R11: fffff52001a45f2b R12: 1ffff92001a45f20
R13: dffffc0000000000 R14: ffffc9000d22f920 R15: ffffc9000d22f920
xas_start+0x1c/0x770 lib/xarray.c:183
xas_load+0x2c/0x5b0 lib/xarray.c:239
filemap_get_entry+0x168/0x2f0 mm/filemap.c:1902
shmem_get_folio_gfp+0x237/0x1660 mm/shmem.c:2457
shmem_get_folio mm/shmem.c:2639 [inline]
shmem_write_begin+0xf7/0x2b0 mm/shmem.c:3289
generic_perform_write+0x2c5/0x900 mm/filemap.c:4242
shmem_file_write_iter+0xf8/0x120 mm/shmem.c:3464
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/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f22fef8da7f
RSP: 002b:00007f22ffe5edf0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000001000000 RCX: 00007f22fef8da7f
RDX: 0000000001000000 RSI: 00007f22f4c00000 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000000 R09: 00000000000050ed
R10: 000020000000a2c2 R11: 0000000000000293 R12: 0000000000000003
R13: 00007f22ffe5eef0 R14: 00007f22ffe5eeb0 R15: 00007f22f4c00000
rcu: rcu_preempt kthread starved for 10501 jiffies! g76133 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:27496 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
__schedule_loop kernel/sched/core.c:7011 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7026
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+0x4bc/0x870 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: 0 UID: 0 PID: 17362 Comm: syz.8.3900 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xd38/0x12d0 kernel/smp.c:877
Code: 89 ee 83 e6 01 31 ff e8 b6 73 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 61 6f 0b 00 eb 38 f3 90 42 0f b6 04 2b <84> c0 75 11 41 f7 04 24 01 00 00 00 74 1e e8 45 6f 0b 00 eb e4 44
RSP: 0018:ffffc9000e21f6c0 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 1ffff11017127ffd RCX: ffff888056803c80
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000e21f840 R08: ffffffff8f7cd377 R09: 1ffffffff1ef9a6e
R10: dffffc0000000000 R11: fffffbfff1ef9a6f R12: ffff8880b893ffe8
R13: dffffc0000000000 R14: ffff8880b883b240 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff88812613e000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f25b47b6d60 CR3: 00000000695f3000 CR4: 0000000000350ef0
Call Trace:
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1043
__flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline]
flush_tlb_multi arch/x86/mm/tlb.c:1381 [inline]
flush_tlb_mm_range+0x6b1/0x12d0 arch/x86/mm/tlb.c:1471
tlb_flush arch/x86/include/asm/tlb.h:23 [inline]
tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:490 [inline]
tlb_flush_mmu+0x1a7/0x680 mm/mmu_gather.c:403
tlb_finish_mmu+0xc3/0x1d0 mm/mmu_gather.c:497
exit_mmap+0x444/0xb40 mm/mmap.c:1293
__mmput+0x118/0x430 kernel/fork.c:1133
exit_mm+0x1da/0x2c0 kernel/exit.c:582
do_exit+0x648/0x2300 kernel/exit.c:954
do_group_exit+0x21c/0x2d0 kernel/exit.c:1107
__do_sys_exit_group kernel/exit.c:1118 [inline]
__se_sys_exit_group kernel/exit.c:1116 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1116
x64_sys_call+0x21f7/0x2200 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbcc2b8efc9
Code: Unable to access opcode bytes at 0x7fbcc2b8ef9f.
RSP: 002b:00007ffed22daac8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fbcc2b8efc9
RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffed22dab2c R08: 00000005d22dabbf R09: 00000000000927c0
R10: 0000000000000001 R11: 0000000000000246 R12: 000000000000022c
R13: 00000000000927c0 R14: 000000000007fdd2 R15: 00007ffed22dab80