On Sun, Sep 2, 2012 at 10:50 PM, Pekka Enberg <penb...@kernel.org> wrote: > On Sun, Sep 2, 2012 at 10:46 AM, Yinghai Lu <ying...@kernel.org> wrote: >> This one intend to fix bugs: >> when efi booting have too many memmap entries, will need to double memblock >> memory array or reserved array. > > Okay, why do we need to do that?
memblock initial memory only have 128 entry, and some EFI system could have more entries than that. So during memblock_x86_fill need to double that array. and efi_reserve_boot_services() could make thing more worse. aka need more entries in memblock.memory.regions. > >> +RESERVE_BRK(early_pgt_alloc, 65536); > > What is this needed for? for extra page table, and extend_brk will consume that. > >> +void __init early_init_mem_mapping(void) >> +{ >> + unsigned long tables; >> + phys_addr_t base; >> + unsigned long start = 0, end = ISA_END_ADDRESS; >> + >> + probe_page_size_mask(); >> + >> + if (max_pfn_mapped) >> + return; > > I find this confusing - what is this protecting for? Why is > 'max_pfn_mapped' set when someone calls early_init_mem_mappings()? for 32 bit, it will non zero max_pfn_mapped set in head_32.S > > Side note: we have multiple "pfn_mapped" globals and it's not at all > obvious to me what the semantics for them are. Maybe adding a comment > or two in arch/x86/include/asm/page_types.h would help. move the comments from arch/x86/kernel/setup.c to that header file ? Thanks Yinghai -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/