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BUG: KMSAN: uninit-value in rcu_segcblist_ready_cbs+0xab/0xe0 kernel/rcu/rcu_segcblist.c:94
CPU: 1 PID: 2595 Comm: udevd Not tainted 4.17.0-rc5+ #99
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+0x149/0x260 mm/kmsan/kmsan.c:1084
 __msan_warning_32+0x6e/0xc0 mm/kmsan/kmsan_instr.c:686
 rcu_segcblist_ready_cbs+0xab/0xe0 kernel/rcu/rcu_segcblist.c:94
 __rcu_pending kernel/rcu/tree.c:3367 [inline]
 rcu_pending kernel/rcu/tree.c:3401 [inline]
 rcu_check_callbacks+0x1b20/0x2a00 kernel/rcu/tree.c:2763
 update_process_times+0x132/0x1a0 kernel/time/timer.c:1636
 tick_sched_handle kernel/time/tick-sched.c:164 [inline]
 tick_sched_timer+0x3ba/0x520 kernel/time/tick-sched.c:1274
 __run_hrtimer kernel/time/hrtimer.c:1398 [inline]
 __hrtimer_run_queues+0xc03/0x15d0 kernel/time/hrtimer.c:1460
 hrtimer_interrupt+0x451/0x13c0 kernel/time/hrtimer.c:1518
 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:863
 </IRQ>
RIP: 0010:__msan_get_context_state+0x20/0xf0 mm/kmsan/kmsan_instr.c:702
RSP: 0018:ffff880199bdfa90 EFLAGS: 00000202 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000000 RBX: ffff880199b6b640 RCX: ffff880000000000
RDX: ffff8801ca13e6c0 RSI: ffff8801b361b640 RDI: ffff880199b6b640
RBP: ffff880199bdfab8 R08: 00000000010000c0 R09: 0000000000000001
R10: 0000000000000002 R11: 0000000000000000 R12: ffff8801b361b6b8
R13: 0000000000000000 R14: 0000000000000000 R15: ffff8801ca13e6c0
 vma_dup_policy+0x1d/0x1a0 mm/mempolicy.c:2102
 dup_mmap kernel/fork.c:455 [inline]
 dup_mm kernel/fork.c:1235 [inline]
 copy_mm kernel/fork.c:1289 [inline]
 copy_process+0x6480/0x9bb0 kernel/fork.c:1795
 _do_fork+0x311/0xf00 kernel/fork.c:2089
 __do_sys_clone kernel/fork.c:2196 [inline]
 __se_sys_clone kernel/fork.c:2190 [inline]
 __x64_sys_clone+0x15e/0x1b0 kernel/fork.c:2190
 do_syscall_64+0x154/0x220 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7fd5ff6a2f46
RSP: 002b:00007fff88d57600 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007fff88d57600 RCX: 00007fd5ff6a2f46
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 00007fff88d57660 R08: 0000000000000a23 R09: 0000000000000a23
R10: 00007fd5fffbfa70 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fff88d57620 R14: 0000000000000005 R15: 0000000000000005

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:279 [inline]
 kmsan_save_stack mm/kmsan/kmsan.c:294 [inline]
 kmsan_internal_chain_origin+0x12b/0x210 mm/kmsan/kmsan.c:685
 __msan_chain_origin+0x69/0xc0 mm/kmsan/kmsan_instr.c:529
 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:2482
 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
Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:279 [inline]
 kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:189
 kmsan_kmalloc+0x94/0x100 mm/kmsan/kmsan.c:315
 kmem_cache_alloc+0xad3/0xb90 mm/slub.c:2772
 alloc_pid+0x7f/0xce0 kernel/pid.c:168
 copy_process+0x3fb7/0x9bb0 kernel/fork.c:1809
 _do_fork+0x311/0xf00 kernel/fork.c:2089
 __do_sys_clone kernel/fork.c:2196 [inline]
 __se_sys_clone kernel/fork.c:2190 [inline]
 __x64_sys_clone+0x15e/0x1b0 kernel/fork.c:2190
 do_syscall_64+0x154/0x220 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
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