On 11/21/2012 12:01 PM, Yinghai Lu wrote: > On Wed, Nov 21, 2012 at 11:56 AM, H. Peter Anvin <hpa at zytor.com> wrote: >> On 11/21/2012 11:54 AM, Yinghai Lu wrote: >>> >>> in kernel arch/x86/kernel/head_64.S >>> >>> it only set first 1G ident mapping. and if it find that code is above >>> 1G, it will set extra ident mapping >>> for new _text.._end. >>> To make checking and add extra mapping simple and also save two extra >>> pages for mapping. >>> Limit that _text.._end in them same GB range. >>> >> >> No, this is backwards. > > old one: it limited bzImage in [0,1G) aka the first 1G. > > Now we can put it in any aligned 1G range. > > So how could it be called backwards? > Because you're adding a more complicated hack. >> >> We should fix that limitation instead. > > sure, but that will make arch/x86/boot/compressed/head_64.S not need > complicated. > But it makes the bootloaders more complicated, and the bootloaders are harder to fix. -hpa
