syzbot

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BUG: KMSAN: uninit-value in __list_add_valid+0x1b6/0x430 lib/list_debug.c:23
CPU: 1 PID: 17325 Comm: vhost-17324 Not tainted 5.5.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1c9/0x220 lib/dump_stack.c:118
 kmsan_report+0x128/0x220 mm/kmsan/kmsan_report.c:108
 __msan_warning+0x57/0xa0 mm/kmsan/kmsan_instr.c:245
 __list_add_valid+0x1b6/0x430 lib/list_debug.c:23
 __list_add include/linux/list.h:60 [inline]
 list_add include/linux/list.h:79 [inline]
 kcov_remote_area_put kernel/kcov.c:142 [inline]
 kcov_remote_stop+0x170/0x2a0 kernel/kcov.c:904
 vhost_worker+0x3ab/0x690 drivers/vhost/vhost.c:363
 kthread+0x4b5/0x4f0 kernel/kthread.c:256
 ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:353

Uninit was created at:
 kmsan_save_stack_with_flags+0x3c/0x90 mm/kmsan/kmsan.c:149
 kmsan_internal_alloc_meta_for_pages mm/kmsan/kmsan_shadow.c:357 [inline]
 kmsan_alloc_page+0x133/0x320 mm/kmsan/kmsan_shadow.c:386
 __alloc_pages_nodemask+0x1421/0x5fd0 mm/page_alloc.c:4799
 alloc_pages_current+0x68d/0x9a0 mm/mempolicy.c:2207
 alloc_pages include/linux/gfp.h:534 [inline]
 __vmalloc_area_node mm/vmalloc.c:2503 [inline]
 __vmalloc_node_range+0x8c9/0x1270 mm/vmalloc.c:2567
 __vmalloc_node mm/vmalloc.c:2627 [inline]
 __vmalloc_node_flags mm/vmalloc.c:2641 [inline]
 vmalloc+0x106/0x120 mm/vmalloc.c:2666
 kcov_remote_start+0x18e/0x2e0 kernel/kcov.c:803
 kcov_remote_start_usb include/linux/kcov.h:52 [inline]
 hub_event+0x190/0x76a0 drivers/usb/core/hub.c:5488
 process_one_work+0x1572/0x1ef0 kernel/workqueue.c:2264
 worker_thread+0x111b/0x2460 kernel/workqueue.c:2410
 kthread+0x4b5/0x4f0 kernel/kthread.c:256
 ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:353
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