Xinxin Jin
2013-Feb-25 19:51 UTC
When does Xen build 1:1 direct mapping of all physical memory ?
Hi, all, I assumed that Xen fills up the page table entires for 1:1 direct mapping of all physical memory at start time, but I cannot find the code. Could anyone tell me when Xen builds up pte for this mapping ? Thanks, -- Xinxin _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel
Jan Beulich
2013-Feb-26 08:31 UTC
Re: When does Xen build 1:1 direct mapping of all physical memory ?
>>> On 25.02.13 at 20:51, Xinxin Jin <xinxinjin89@gmail.com> wrote: > I assumed that Xen fills up the page table entires for 1:1 direct mapping > of all physical memory at start time, but I cannot find the code. Could > anyone tell me when Xen builds up pte for this mapping ?xen/arch/x86/mm.c:init_frametable() Jan
Xinxin Jin
2013-Feb-26 22:23 UTC
Re: When does Xen build 1:1 direct mapping of all physical memory ?
Hi Jan, I think init_frametable() is to initialize frame table, whose virtual address starts at FRAMETABLE_VIRT_START ? How about the direct 1:1 mapping of all of machine memroy whose virtual address start at DIRECTMAP_VIRT_START? Thanks, On Tue, Feb 26, 2013 at 12:31 AM, Jan Beulich <JBeulich@suse.com> wrote:> >>> On 25.02.13 at 20:51, Xinxin Jin <xinxinjin89@gmail.com> wrote: > > I assumed that Xen fills up the page table entires for 1:1 direct mapping > > of all physical memory at start time, but I cannot find the code. Could > > anyone tell me when Xen builds up pte for this mapping ? > > xen/arch/x86/mm.c:init_frametable() > > Jan > >-- Xinxin _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel
Jan Beulich
2013-Feb-27 07:37 UTC
Re: When does Xen build 1:1 direct mapping of all physical memory ?
>>> On 26.02.13 at 23:23, Xinxin Jin <xinxinjin89@gmail.com> wrote: > Hi Jan, I think init_frametable() is to initialize frame table, whose > virtual address starts at FRAMETABLE_VIRT_START ? How about the direct 1:1 > mapping of all of machine memroy whose virtual address start at > DIRECTMAP_VIRT_START?Oh, sorry, yes, this isn''t the direct mapping. Check the calls to map_pages_to_xen() in __start_xen() for the direct mapping. Jan