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BUG: KMSAN: uninit-value in task_stack_page include/linux/sched/task_stack.h:21 [inline]
BUG: KMSAN: uninit-value in last_frame arch/x86/kernel/unwind_frame.c:96 [inline]
BUG: KMSAN: uninit-value in is_last_frame arch/x86/kernel/unwind_frame.c:101 [inline]
BUG: KMSAN: uninit-value in is_last_task_frame arch/x86/kernel/unwind_frame.c:170 [inline]
BUG: KMSAN: uninit-value in unwind_next_frame+0x537/0xf30 arch/x86/kernel/unwind_frame.c:294
CPU: 1 PID: 14791 Comm: kworker/u4:19 Not tainted 4.20.0-rc7+ #12
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+0x173/0x1d0 lib/dump_stack.c:113
 kmsan_report+0x12e/0x2a0 mm/kmsan/kmsan.c:611
 __msan_warning+0x81/0xf0 mm/kmsan/kmsan_instr.c:295
 task_stack_page include/linux/sched/task_stack.h:21 [inline]
 last_frame arch/x86/kernel/unwind_frame.c:96 [inline]
 is_last_frame arch/x86/kernel/unwind_frame.c:101 [inline]
 is_last_task_frame arch/x86/kernel/unwind_frame.c:170 [inline]
 unwind_next_frame+0x537/0xf30 arch/x86/kernel/unwind_frame.c:294
 __save_stack_trace+0x78b/0xb90 arch/x86/kernel/stacktrace.c:44
 save_stack_trace+0xa2/0xe0 arch/x86/kernel/stacktrace.c:60
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:202 [inline]
 kmsan_internal_poison_shadow+0x92/0x150 mm/kmsan/kmsan.c:156
 kmsan_kmalloc+0xac/0x130 mm/kmsan/kmsan_hooks.c:176
 kmem_cache_alloc+0x572/0xb90 mm/slub.c:2777
 skb_clone+0x300/0x580 net/core/skbuff.c:1280
 skb_share_check include/linux/skbuff.h:1568 [inline]
 packet_rcv_spkt+0x25b/0x960 net/packet/af_packet.c:1817
 deliver_skb net/core/dev.c:1945 [inline]
 deliver_ptype_list_skb net/core/dev.c:1960 [inline]
 __netif_receive_skb_core+0x36c4/0x52c0 net/core/dev.c:4904
 __netif_receive_skb_one_core net/core/dev.c:4944 [inline]
 __netif_receive_skb net/core/dev.c:5056 [inline]
 netif_receive_skb_internal+0x4d8/0x9a0 net/core/dev.c:5159
 napi_skb_finish net/core/dev.c:5616 [inline]
 napi_gro_receive+0x664/0xad0 net/core/dev.c:5647
 receive_buf+0x598a/0x8230 drivers/net/virtio_net.c:1041
 virtnet_receive drivers/net/virtio_net.c:1303 [inline]
 virtnet_poll+0xddf/0x1c60 drivers/net/virtio_net.c:1390
 napi_poll net/core/dev.c:6287 [inline]
 net_rx_action+0x816/0x1aa0 net/core/dev.c:6353
 __do_softirq+0x53f/0x93a kernel/softirq.c:293
 invoke_softirq kernel/softirq.c:375 [inline]
 irq_exit+0x214/0x250 kernel/softirq.c:416
 exiting_irq arch/x86/include/asm/apic.h:536 [inline]
 do_IRQ+0x2bb/0x3b0 arch/x86/kernel/irq.c:258
 common_interrupt+0x2e/0x2e arch/x86/entry/entry_64.S:588
 </IRQ>
RIP: 0010:_raw_spin_unlock_irqrestore+0x4b/0x70 kernel/locking/spinlock.c:185
Code: 00 8b b8 88 0c 00 00 48 8b 00 48 85 c0 75 28 48 89 df e8 98 6c 4a f7 c6 00 00 c6 03 00 4d 85 e4 75 1c 4c 89 7d d8 ff 75 d8 9d <48> 83 c4 08 5b 41 5c 41 5e 41 5f 5d c3 e8 83 76 4a f7 eb d1 44 89
RSP: 0018:ffff888113cdfe30 EFLAGS: 00000286 ORIG_RAX: ffffffffffffffd8
RAX: ffff8881128afaf8 RBX: ffff88811289faf8 RCX: ffff8881128afaf8
RDX: ffff8881128bfaf8 RSI: 0000160000000000 RDI: ccccccccccccd000
RBP: ffff888113cdfe58 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: ffffffff81494230 R12: 0000000000000000
R13: ffff88811289faf0 R14: 0000000000000000 R15: 0000000000000286
 spin_unlock_irqrestore include/linux/spinlock.h:384 [inline]
 complete+0x10e/0x170 kernel/sched/completion.c:37
 kthread+0x3c6/0x4e0 kernel/kthread.c:240
 ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:355

Local variable description: ----__ret.i.i.i.i@kmem_cache_free
Variable was created at:
 kmem_cache_free+0xdc/0x2b70 mm/slub.c:3023
 kfree_skbmem net/core/skbuff.c:603 [inline]
 __kfree_skb+0x1e2/0x210 net/core/skbuff.c:642
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