Hi Julien, On Tue, May 31, 2016 at 12:07:58PM +0100, Julien Grall wrote: >Hi Peng, > >On 27/05/16 11:23, Peng Fan wrote: >>To ARM64, we should use '(VMAP_VIRT_START + GB(1))' as VMAP_VIRT_END, > >s/To/For/
Fix in V2. > >>but not '(VMAP_VIRT_START + GB(1) - 1)'. >> >>Seeing 'vm_end[type] = PFN_DOWN(end - start);' in vm_init_type, >>if not correct VMAP_VIRT_END, one page is wasted. > >I find difficult to parse the commit message. How about: Sorry (: > >"xen/arm64: config: Correctly define VMAP_VIRT_END > >The vmap initialization code (vm_init_type) will round down the end of the >region to a page-aligned address. > >On ARM64, the default vmap region is located between 1G and 2G. Based on the >initialization code, the end address is excluded of the region. > >Therefore the current definition of VMAP_VIRT_END will lead the vmap code to >not use the last 4K of the region. > >Fix it by defining VMAP_VIRT_END as "VMAP_VIRT_START + GB(1)". >" Thanks for your good description. Thanks, Peng. > >> >>Signed-off-by: Peng Fan <van.free...@gmail.com> >>Cc: Julien Grall <julien.gr...@arm.com> >>Cc: Stefano Stabellini <sstabell...@kernel.org> >>--- >> >>I found X86 use '(VMAP_VIRT_START + GB(64))' and ARM32 use XENHEAP_VIRT_START, >>both are aligned address. So, I think ARM64 may also need to use aligned >>address. I am not very sure (: > >Correct, this should be aligned to avoid wasting a page. > >> >> xen/include/asm-arm/config.h | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >>diff --git a/xen/include/asm-arm/config.h b/xen/include/asm-arm/config.h >>index 2d11b62..f92c0a0 100644 >>--- a/xen/include/asm-arm/config.h >>+++ b/xen/include/asm-arm/config.h >>@@ -147,7 +147,7 @@ >> #define SLOT0_ENTRY_SIZE SLOT0(1) >> >> #define VMAP_VIRT_START GB(1) >>-#define VMAP_VIRT_END (VMAP_VIRT_START + GB(1) - 1) >>+#define VMAP_VIRT_END (VMAP_VIRT_START + GB(1)) >> >> #define FRAMETABLE_VIRT_START GB(32) >> #define FRAMETABLE_SIZE GB(32) >> > >Regards, > >-- >Julien Grall _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel
