syzbot

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P31094/2:b..l P31135/3:b..l
rcu: 	(detected by 1, t=10502 jiffies, g=137957, q=1076 ncpus=2)
task:syz.6.9139      state:R  running task     stack:25944 pid:31135 tgid:31130 ppid:26455  task_flags:0x400040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x145f/0x5070 kernel/sched/core.c:6863
 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7190
 irqentry_exit+0x5e3/0x670 kernel/entry/common.c:216
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x222/0x340 kernel/locking/lockdep.c:5872
Code: ff ff ff e8 d0 40 35 09 f7 44 24 08 00 02 00 00 0f 84 3a ff ff ff 65 48 8b 05 aa 9f 16 10 48 3b 44 24 58 75 33 fb 48 83 c4 60 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 4f ff 38 09 cc 48 8d 3d a7 c9 41
RSP: 0018:ffffc90004b3f4c0 EFLAGS: 00000286
RAX: 1902d30790721f00 RBX: 0000000000000000 RCX: 0000000000000046
RDX: 00000000ef846500 RSI: ffffffff8cfdf9c8 RDI: ffffffff8b3f5ae0
RBP: ffffffff820eb12e R08: ffffffff820eb12e R09: ffff888062cef598
R10: dffffc0000000000 R11: fffff940005903e1 R12: 0000000000000000
R13: ffff888062cef598 R14: 0000000000000001 R15: 0000000000000246
 rt_spin_lock+0x88/0x3e0 kernel/locking/spinlock_rt.c:56
 spin_lock include/linux/spinlock_rt.h:44 [inline]
 __pte_offset_map_lock+0x13e/0x210 mm/pgtable-generic.c:403
 pte_offset_map_lock include/linux/mm.h:3361 [inline]
 filemap_map_pages+0x616/0x1cc0 mm/filemap.c:3903
 do_fault_around mm/memory.c:5713 [inline]
 do_read_fault mm/memory.c:5746 [inline]
 do_fault mm/memory.c:5889 [inline]
 do_pte_missing+0x175b/0x27a0 mm/memory.c:4401
 handle_pte_fault mm/memory.c:6273 [inline]
 __handle_mm_fault mm/memory.c:6411 [inline]
 handle_mm_fault+0xcc1/0x1330 mm/memory.c:6580
 faultin_page mm/gup.c:1126 [inline]
 __get_user_pages+0x166e/0x2830 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]
 vm_mmap_pgoff+0x38a/0x4d0 mm/util.c:586
 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: 0033:0x7f25fd09f749
RSP: 002b:00007f25fb2dd038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007f25fd2f6090 RCX: 00007f25fd09f749
RDX: b635773f06ebbeee RSI: 0000000000b36000 RDI: 0000200000000000
RBP: 00007f25fd123f91 R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f25fd2f6128 R14: 00007f25fd2f6090 R15: 00007ffc527ea188
 </TASK>
task:syz.3.9127      state:R  running task     stack:24952 pid:31094 tgid:31094 ppid:30245  task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x145f/0x5070 kernel/sched/core.c:6863
 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7190
 irqentry_exit+0x5e3/0x670 kernel/entry/common.c:216
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:orc_ip arch/x86/kernel/unwind_orc.c:81 [inline]
RIP: 0010:__orc_find arch/x86/kernel/unwind_orc.c:103 [inline]
RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:238 [inline]
RIP: 0010:unwind_next_frame+0x51a/0x23d0 arch/x86/kernel/unwind_orc.c:510
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:ffffc90004cff598 EFLAGS: 00000246
RAX: fffffffff79f94f9 RBX: ffffffff8f2f601c RCX: dffffc0000000000
RDX: ffffffff8f2f6004 RSI: ffffffff8fc41808 RDI: ffffffff8b3f5a80
RBP: ffffffff8f2f6004 R08: 0000000000000007 R09: ffffffff8d5ae940
R10: ffffc90004cff6b8 R11: ffffffff81ab9960 R12: ffffffff86cef5c8
R13: ffffffff8f2f6004 R14: ffffc90004cff668 R15: ffffffff8f2f6010
 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
 __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415
 kasan_kmalloc include/linux/kasan.h:263 [inline]
 __do_kmalloc_node mm/slub.c:5657 [inline]
 __kmalloc_noprof+0x23e/0x7e0 mm/slub.c:5669
 kmalloc_noprof include/linux/slab.h:961 [inline]
 raw_event_queue_add drivers/usb/gadget/legacy/raw_gadget.c:73 [inline]
 raw_queue_event+0x83/0x2e0 drivers/usb/gadget/legacy/raw_gadget.c:240
 gadget_suspend+0x51/0xf0 drivers/usb/gadget/legacy/raw_gadget.c:398
 set_link_state+0xb9b/0x1220 drivers/usb/gadget/udc/dummy_hcd.c:-1
 dummy_pullup+0xc9/0x1e0 drivers/usb/gadget/udc/dummy_hcd.c:910
 usb_gadget_disconnect_locked+0x143/0x490 drivers/usb/gadget/udc/core.c:780
 gadget_unbind_driver+0xc7/0x460 drivers/usb/gadget/udc/core.c:1685
 device_remove drivers/base/dd.c:569 [inline]
 __device_release_driver drivers/base/dd.c:1282 [inline]
 device_release_driver_internal+0x46f/0x800 drivers/base/dd.c:1305
 driver_detach+0x1f3/0x2d0 drivers/base/dd.c:1368
 bus_remove_driver+0x229/0x320 drivers/base/bus.c:784
 usb_gadget_unregister_driver+0x4e/0x70 drivers/usb/gadget/udc/core.c:1751
 raw_release+0xd2/0x260 drivers/usb/gadget/legacy/raw_gadget.c:463
 __fput+0x45b/0xa80 fs/file_table.c:468
 task_work_run+0x1d4/0x260 kernel/task_work.c:233
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 __exit_to_user_mode_loop kernel/entry/common.c:44 [inline]
 exit_to_user_mode_loop+0xef/0x4e0 kernel/entry/common.c:75
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
 do_syscall_64+0x2c1/0xf80 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe89ffbf749
RSP: 002b:00007ffe3a25a678 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 000000000013d029 RCX: 00007fe89ffbf749
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007fe8a0217da0 R08: 0000000000000001 R09: 0000000c3a25a96f
R10: 0000001b2de20000 R11: 0000000000000246 R12: 00007fe8a0215fac
R13: 00007fe8a0215fa0 R14: ffffffffffffffff R15: 00007ffe3a25a790
 </TASK>
rcu: rcu_preempt kthread starved for 10399 jiffies! g137957 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:27544 pid:18    tgid:18    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x145f/0x5070 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
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Tainted: G             L      syzkaller #0 PREEMPT_{RT,(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: cc cc cc cc 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 23 97 16 00 f3 0f 1e fa fb f4 <c3> cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc900001d7e20 EFLAGS: 000002c2
RAX: 000000000089a7bf RBX: ffffffff8195d83e RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8ce0c91e RDI: ffffffff8b3f5ae0
RBP: ffffc900001d7f10 R08: ffff8880b8933c5b R09: 1ffff1101712678b
R10: dffffc0000000000 R11: ffffed101712678c R12: ffffffff8edb3670
R13: 1ffff11003757b58 R14: 0000000000000001 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff888126dee000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f84c2d2cd58 CR3: 000000002f08e000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 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
 </TASK>