[v5 10/15] x86/kasan: explicitly zero kasan shadow memory

To optimize the performance of struct page initialization, vmemmap_populate() will no longer zero memory. We must explicitly zero the memory that is allocated by vmemmap_populate() for kasan, as this memory does not go through struct page initialization path. Signed-off-by: Pavel Tatashin

[v5 10/15] x86/kasan: explicitly zero kasan shadow memory

To optimize the performance of struct page initialization, vmemmap_populate() will no longer zero memory. We must explicitly zero the memory that is allocated by vmemmap_populate() for kasan, as this memory does not go through struct page initialization path. Signed-off-by: Pavel Tatashin