syzbot

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P16870/1:b..l
	(detected by 0, t=10502 jiffies, g=103609, q=71 ncpus=2)
task:syz.5.2691      state:R  running task     stack:24808 pid:16870 ppid:5282   flags:0x00404000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x143f/0x4570 kernel/sched/core.c:6561
 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6873
 irqentry_exit+0x53/0x80 kernel/entry/common.c:439
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:lock_is_held_type+0x137/0x180 arch/x86/include/asm/irqflags.h:-1
Code: 75 40 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 75 46 41 f7 c4 00 02 00 00 74 01 fb 65 48 8b 04 25 28 00 00 00 <48> 3b 44 24 08 75 3c 89 e8 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f
RSP: 0018:ffffc9000d58f618 EFLAGS: 00000206
RAX: 941d193eb94c3100 RBX: 0000000000000001 RCX: 0000000080000000
RDX: ffff888026541dc0 RSI: ffffffff8b0c3040 RDI: ffffffff8b5f7360
RBP: 0000000000000001 R08: ffffffff81b7f818 R09: fffff94000254017
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000246
R13: ffff888026541dc0 R14: 00000000ffffffff R15: ffffffff8d32e7c0
 xa_entry include/linux/xarray.h:1198 [inline]
 xas_reload+0x1a4/0x470 include/linux/xarray.h:1583
 next_uptodate_page+0x214/0xb70 mm/filemap.c:3390
 first_map_page mm/filemap.c:3417 [inline]
 filemap_map_pages+0x33d/0x12c0 mm/filemap.c:3444
 do_fault_around mm/memory.c:4600 [inline]
 do_read_fault mm/memory.c:4626 [inline]
 do_fault mm/memory.c:4760 [inline]
 handle_pte_fault mm/memory.c:5031 [inline]
 __handle_mm_fault mm/memory.c:5173 [inline]
 handle_mm_fault+0x33e0/0x5340 mm/memory.c:5294
 faultin_page mm/gup.c:1026 [inline]
 __get_user_pages+0x4f3/0x1190 mm/gup.c:1250
 populate_vma_page_range+0x217/0x2b0 mm/gup.c:1607
 __mm_populate+0x275/0x440 mm/gup.c:1721
 mm_populate include/linux/mm.h:2823 [inline]
 vm_mmap_pgoff+0x22b/0x2d0 mm/util.c:525
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f0322f8e169
RSP: 002b:00007f0323dad038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007f03231b5fa0 RCX: 00007f0322f8e169
RDX: b635773f06ebbeee RSI: 0000000000b36000 RDI: 0000200000000000
RBP: 00007f0323010a68 R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f03231b5fa0 R15: 00007fff754c8d58
 </TASK>
rcu: rcu_preempt kthread starved for 10526 jiffies! g103609 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:26656 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x143f/0x4570 kernel/sched/core.c:6561
 schedule+0xbf/0x180 kernel/sched/core.c:6637
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1965
 rcu_gp_fqs_loop+0x2d2/0x1150 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0xa3/0x3b0 kernel/rcu/tree.c:1905
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 PID: 16861 Comm: syz.2.2689 Not tainted 6.1.134-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:244 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x4/0x80 kernel/kcov.c:320
Code: 89 f8 89 f6 49 ff c2 4c 89 11 48 c7 44 0a 08 05 00 00 00 48 89 44 0a 10 48 89 74 0a 18 4c 89 44 0a 20 c3 0f 1f 00 4c 8b 04 24 <65> 48 8b 0d 04 c1 77 7e 65 8b 05 05 c1 77 7e 25 00 01 ff 00 74 10
RSP: 0018:ffffc9000d697b38 EFLAGS: 00000246
RAX: 1ffff110055e8b28 RBX: 0000000000000004 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000000
RBP: ffffc9000d697c70 R08: ffffffff8156fea2 R09: ffffed10055e8b29
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff88802e09ca40
R13: ffff88802af45940 R14: ffffc9000d697f58 R15: ffff88802af45940
FS:  00007f0c9279d6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c3ee484 CR3: 00000000439f6000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 get_signal+0x162/0x17a0 kernel/signal.c:2650
 arch_do_signal_or_restart+0xb0/0x1a10 arch/x86/kernel/signal.c:871
 exit_to_user_mode_loop+0x6a/0x100 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f0c9198e169
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f0c9279d0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f0c91bb5fa8 RCX: 00007f0c9198e169
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f0c91bb5fa8
RBP: 00007f0c91bb5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f0c91bb5fac
R13: 0000000000000000 R14: 00007ffc629b2020 R15: 00007ffc629b2108
 </TASK>