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BUG: KMSAN: uninit-value in rcu_segcblist_ready_cbs+0xab/0xe0 kernel/rcu/rcu_segcblist.c:94
CPU: 0 PID: 12863 Comm: syz-executor5 Not tainted 4.16.0+ #87
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x185/0x1d0 lib/dump_stack.c:53
 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067
 __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:683
 rcu_segcblist_ready_cbs+0xab/0xe0 kernel/rcu/rcu_segcblist.c:94
 __rcu_pending kernel/rcu/tree.c:3378 [inline]
 rcu_pending kernel/rcu/tree.c:3423 [inline]
 rcu_check_callbacks+0x1cb8/0x2cd0 kernel/rcu/tree.c:2763
 update_process_times+0x132/0x1a0 kernel/time/timer.c:1636
 tick_sched_handle kernel/time/tick-sched.c:162 [inline]
 tick_sched_timer+0x33b/0x4b0 kernel/time/tick-sched.c:1194
 __run_hrtimer kernel/time/hrtimer.c:1349 [inline]
 __hrtimer_run_queues+0xc03/0x15d0 kernel/time/hrtimer.c:1411
 hrtimer_interrupt+0x426/0xaf0 kernel/time/hrtimer.c:1469
 local_apic_timer_interrupt+0x66/0x230 arch/x86/kernel/apic/apic.c:1025
 smp_apic_timer_interrupt+0x5a/0x90 arch/x86/kernel/apic/apic.c:1053
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:857
 </IRQ>
RIP: 0010:clear_page_erms+0x9/0x10 arch/x86/lib/clear_page_64.S:50
RSP: 0018:ffff8801a9d1f600 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff12
RAX: 0000000000000000 RBX: ffff88016bbc5418 RCX: 0000000000000000
RDX: ffff88016e6f5418 RSI: aaaaaaaaaaaab000 RDI: ffff8801565ad000
RBP: ffff8801a9d1f6a8 R08: 0000000001080020 R09: 0000000000000002
R10: ffffffff7fffffff R11: 0000000000100000 R12: 0000000000000000
R13: ffff8801565ac000 R14: ffff8801a9d1f608 R15: 0000000000000001
 __do_huge_pmd_anonymous_page mm/huge_memory.c:571 [inline]
 do_huge_pmd_anonymous_page+0x133e/0x2520 mm/huge_memory.c:729
 create_huge_pmd mm/memory.c:3870 [inline]
 __handle_mm_fault mm/memory.c:4074 [inline]
 handle_mm_fault+0x428f/0x7e50 mm/memory.c:4140
 __do_page_fault+0xec4/0x1a10 arch/x86/mm/fault.c:1423
 do_page_fault+0xd3/0x260 arch/x86/mm/fault.c:1500
 page_fault+0x25/0x50 arch/x86/entry/entry_64.S:1151
RIP: 0010:filldir64+0x30c/0x800 fs/readdir.c:273
RSP: 0018:ffff8801a9d1fb60 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000020e25000 RCX: 000000000000b0b7
RDX: ffff8801c53ffdf8 RSI: 0000000000000000 RDI: ffffea0000000000
RBP: ffff8801a9d1fc48 R08: 0000000001080020 R09: 0000000000000002
R10: 0000000000000004 R11: 0000000000000000 R12: 0000000000000000
R13: ffff88016bbc4418 R14: 0000000000000000 R15: ffff8801a9d1fdf8
 dir_emit_dot include/linux/fs.h:3371 [inline]
 dir_emit_dots include/linux/fs.h:3382 [inline]
 proc_ns_dir_readdir+0x471/0x940 fs/proc/namespaces.c:122
 iterate_dir+0x3d4/0x860 fs/readdir.c:53
 SYSC_getdents64+0x235/0x4f0 fs/readdir.c:314
 SyS_getdents64+0x54/0x80 fs/readdir.c:295
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
RIP: 0033:0x455979
RSP: 002b:00007f9a7be88c68 EFLAGS: 00000246 ORIG_RAX: 00000000000000d9
RAX: ffffffffffffffda RBX: 00007f9a7be896d4 RCX: 0000000000455979
RDX: 00000000000013b4 RSI: 0000000020e25000 RDI: 0000000000000013
RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000000aa R14: 00000000006f5090 R15: 0000000000000000

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:3060
 call_rcu_sched+0x32/0x40 kernel/rcu/tree.c:3100
 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:809
 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+0x36d/0x430 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
Local variable description: ----tlb.i@ldt_arch_exit_mmap
Variable was created at:
 ldt_arch_exit_mmap+0x46/0x160 arch/x86/kernel/ldt.c:298
 arch_exit_mmap arch/x86/include/asm/mmu_context.h:244 [inline]
 exit_mmap+0x30f/0x950 mm/mmap.c:3009
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