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IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready
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BUG: KMSAN: uninit-value in pcpu_addr_in_chunk mm/percpu.c:208 [inline]
BUG: KMSAN: uninit-value in pcpu_chunk_addr_search mm/percpu.c:1308 [inline]
BUG: KMSAN: uninit-value in free_percpu+0x2b8/0xb30 mm/percpu.c:1723
CPU: 1 PID: 32683 Comm: blkid Not tainted 4.17.0+ #7
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+0x188/0x2a0 mm/kmsan/kmsan.c:1121
 __msan_warning_32+0x70/0xc0 mm/kmsan/kmsan_instr.c:620
 pcpu_addr_in_chunk mm/percpu.c:208 [inline]
 pcpu_chunk_addr_search mm/percpu.c:1308 [inline]
 free_percpu+0x2b8/0xb30 mm/percpu.c:1723
 ip6_dst_destroy+0x157/0x750 net/ipv6/route.c:398
 dst_destroy+0x20e/0x7a0 net/core/dst.c:131
 dst_destroy_rcu+0x46/0x50 net/core/dst.c:153
 __rcu_reclaim kernel/rcu/rcu.h:178 [inline]
 rcu_do_batch kernel/rcu/tree.c:2675 [inline]
 invoke_rcu_callbacks kernel/rcu/tree.c:2930 [inline]
 __rcu_process_callbacks kernel/rcu/tree.c:2897 [inline]
 rcu_process_callbacks+0x18dd/0x2060 kernel/rcu/tree.c:2914
 __do_softirq+0x592/0x979 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:anon_vma_prepare include/linux/rmap.h:150 [inline]
RIP: 0010:do_cow_fault mm/memory.c:3650 [inline]
RIP: 0010:do_fault mm/memory.c:3736 [inline]
RIP: 0010:handle_pte_fault mm/memory.c:3965 [inline]
RIP: 0010:__handle_mm_fault mm/memory.c:4089 [inline]
RIP: 0010:handle_mm_fault+0x45ca/0x7ed0 mm/memory.c:4126
RSP: 0000:ffff88008490fc70 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000000 RBX: ffff88012973a618 RCX: ffff880000000000
RDX: ffff880083611b78 RSI: aaaaaaaaaaaab000 RDI: ffffea0000000000
RBP: ffff88008490fdf0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: ffff88008824faf0 R14: 0000000000000000 R15: 0000000000000000
 __do_page_fault+0xec6/0x1a10 arch/x86/mm/fault.c:1400
 do_page_fault+0xb7/0x250 arch/x86/mm/fault.c:1477
 page_fault+0x1e/0x30 arch/x86/entry/entry_64.S:1160
RIP: 0033:0x7f9646fa12d6
RSP: 002b:00007fff91a71cc8 EFLAGS: 00010202
RAX: 00007f9646f89878 RBX: 00007f96471a84c8 RCX: 000000000000008a
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00007f9646f898a8
RBP: 00007fff91a71f90 R08: 0000000000000030 R09: 0101010101010101
R10: 00007f9646f898a8 R11: 00007f9646fa12d6 R12: 00007fff91a72078
R13: 0000000000000002 R14: 00007fff91a71d40 R15: 00007fff91a71d10

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:464
 ip6_dst_alloc net/ipv6/route.c:379 [inline]
 icmp6_dst_alloc+0x673/0xc70 net/ipv6/route.c:2461
 mld_sendpack+0x70c/0x11d0 net/ipv6/mcast.c:1647
 mld_send_cr net/ipv6/mcast.c:1954 [inline]
 mld_ifc_timer_expire+0x126b/0x15a0 net/ipv6/mcast.c:2451
 call_timer_fn+0x280/0x5d0 kernel/time/timer.c:1326
 expire_timers kernel/time/timer.c:1363 [inline]
 __run_timers+0xd96/0x11b0 kernel/time/timer.c:1666
 run_timer_softirq+0x43/0x70 kernel/time/timer.c:1692
 __do_softirq+0x592/0x979 kernel/softirq.c:285
Local variable description: ----flags.i.i.i.i@_raw_spin_lock_irqsave
Variable was created at:
 _raw_spin_lock_irqsave+0x45/0xf0 kernel/locking/spinlock.c:150
 pcpu_alloc+0x4c2/0x2040 mm/percpu.c:1388
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