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BUG: KMSAN: uninit-value in rcu_segcblist_pend_cbs+0xa9/0xf0 kernel/rcu/rcu_segcblist.c:104
CPU: 0 PID: 20935 Comm: udevd Not tainted 4.17.0-rc3+ #90
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x185/0x1d0 lib/dump_stack.c:113
 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067
 __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:683
 rcu_segcblist_pend_cbs+0xa9/0xf0 kernel/rcu/rcu_segcblist.c:104
 rcu_accelerate_cbs+0x7e/0xca0 kernel/rcu/tree.c:1810
 rcu_report_qs_rdp kernel/rcu/tree.c:2514 [inline]
 rcu_check_quiescent_state kernel/rcu/tree.c:2553 [inline]
 __rcu_process_callbacks kernel/rcu/tree.c:2881 [inline]
 rcu_process_callbacks+0x6eb/0x2020 kernel/rcu/tree.c:2914
 __do_softirq+0x56d/0x93d kernel/softirq.c:285
 invoke_softirq kernel/softirq.c:365 [inline]
 irq_exit+0x202/0x240 kernel/softirq.c:405
 exiting_irq+0xe/0x10 arch/x86/include/asm/apic.h:525
 smp_apic_timer_interrupt+0x64/0x90 arch/x86/kernel/apic/apic.c:1055
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:863
 </IRQ>
RIP: 0010:native_restore_fl arch/x86/include/asm/irqflags.h:37 [inline]
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/irqflags.h:78 [inline]
RIP: 0010:__msan_poison_alloca+0x14c/0x1d0 mm/kmsan/kmsan_instr.c:651
RSP: 0018:ffff8801ca31f990 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 000000008b60000a RBX: 000000008b60000a RCX: ffff8801ca31f9d0
RDX: 0000000000000004 RSI: 0000000000000004 RDI: 00000000f0989424
RBP: ffff8801ca31fa30 R08: 0000000001080020 R09: 0000000000000002
R10: 0000000000000002 R11: 0000000000000000 R12: 0000000000000000
R13: ffffffff8accf4a0 R14: 0000000000000246 R15: ffff8801690057c0
 path_openat+0xa4/0x6450 fs/namei.c:3471
 do_filp_open+0x261/0x640 fs/namei.c:3535
 do_sys_open+0x624/0x960 fs/open.c:1093
 __do_sys_open fs/open.c:1111 [inline]
 __se_sys_open fs/open.c:1106 [inline]
 __x64_sys_open+0xf2/0x130 fs/open.c:1106
 do_syscall_64+0x154/0x220 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7f2f6889e120
RSP: 002b:00007ffd69592bf8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00000000ffffffff RCX: 00007f2f6889e120
RDX: 0000000001db3460 RSI: 0000000000000002 RDI: 000000000041c571
RBP: 0000000000625500 R08: 0000000000000a21 R09: 0000000000000a21
R10: 00007f2f685c3240 R11: 0000000000000246 R12: 0000000001dab4b0
R13: 0000000000000007 R14: 0000000001d9a250 R15: 0000000000000005

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:278 [inline]
 kmsan_save_stack mm/kmsan/kmsan.c:293 [inline]
 kmsan_internal_chain_origin+0x12b/0x210 mm/kmsan/kmsan.c:684
 __msan_chain_origin+0x69/0xc0 mm/kmsan/kmsan_instr.c:528
 rcu_segcblist_enqueue+0x275/0x2d0 kernel/rcu/rcu_segcblist.c:151
 __call_rcu+0x227/0xef0 kernel/rcu/tree.c:3057
 call_rcu_sched+0x32/0x40 kernel/rcu/tree.c:3097
 release_task+0x24b9/0x2530 kernel/exit.c:223
 exit_notify kernel/exit.c:736 [inline]
 do_exit+0x2d91/0x38d0 kernel/exit.c:887
 do_group_exit+0x1a0/0x360 kernel/exit.c:970
 get_signal+0x1320/0x1f20 kernel/signal.c:2469
 do_signal+0xb8/0x1c80 arch/x86/kernel/signal.c:810
 exit_to_usermode_loop arch/x86/entry/common.c:162 [inline]
 prepare_exit_to_usermode+0x271/0x3a0 arch/x86/entry/common.c:196
 syscall_return_slowpath+0xe9/0x700 arch/x86/entry/common.c:265
 do_syscall_64+0x1a6/0x220 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
Local variable description: ----ac@__alloc_pages_nodemask
Variable was created at:
 __alloc_pages_nodemask+0x196/0x5dd0 mm/page_alloc.c:4355
 alloc_pages_current+0x6b5/0x970 mm/mempolicy.c:2093
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