Hi Akashi, On 12/01/2016:03:23:42 PM, Pratyush Anand wrote: > > >+static void init_page_table(void) > > >+{ > > >+ inval_cache_range((uint64_t)page_table, > > >+ (uint64_t)page_table + PAGE_TABLE_SIZE); > > >+ memset(page_table, 0, PAGE_TABLE_SIZE); > > > > why invalidate first? > > Humm..may be you are right. It was copied from arch/arm64/kernel/head.S. > http://lxr.free-electrons.com/source/arch/arm64/kernel/head.S#L322 I am not yet sure about the cache eviction policy on different arch. So as per kernel code's comment (Invalidate the idmap and swapper page tables to avoid potential dirty cache lines being evicted.), I would like to keep it here. May be I will add similar comment here as well. ~Pratyush