syzbot

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BUG: KMSAN: uninit-value in build_id_parse+0x493/0x1030 lib/buildid.c:147
 build_id_parse+0x493/0x1030 lib/buildid.c:147
 perf_event_mmap_event kernel/events/core.c:8435 [inline]
 perf_event_mmap+0x29ba/0x2aa0 kernel/events/core.c:8578
 mmap_region+0x20a8/0x3e10 mm/mmap.c:1846
 do_mmap+0x1843/0x2310 mm/mmap.c:1575
 vm_mmap_pgoff+0x362/0x570 mm/util.c:519
 ksys_mmap_pgoff+0x580/0xa70 mm/mmap.c:1623
 __do_sys_mmap arch/x86/kernel/sys_x86_64.c:96 [inline]
 __se_sys_mmap arch/x86/kernel/sys_x86_64.c:89 [inline]
 __x64_sys_mmap+0x1e0/0x250 arch/x86/kernel/sys_x86_64.c:89
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Uninit was created at:
 __alloc_pages+0xbc7/0x10a0 mm/page_alloc.c:5409
 __alloc_pages_node include/linux/gfp.h:570 [inline]
 khugepaged_alloc_page mm/khugepaged.c:884 [inline]
 collapse_file+0x473/0x60c0 mm/khugepaged.c:1658
 khugepaged_scan_file mm/khugepaged.c:2059 [inline]
 khugepaged_scan_mm_slot+0x2df8/0x3890 mm/khugepaged.c:2154
 khugepaged_do_scan+0x40b/0x940 mm/khugepaged.c:2238
 khugepaged+0xb5/0x1410 mm/khugepaged.c:2283
 kthread+0x721/0x850 kernel/kthread.c:327
 ret_from_fork+0x1f/0x30

CPU: 1 PID: 20747 Comm: syz-executor.3 Not tainted 5.16.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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