From 17880a0f10421c5e456d593c70da03b1688d34ac Mon Sep 17 00:00:00 2001 From: Jan Beulich Date: Fri, 12 May 2017 17:24:17 +0200 Subject: [PATCH] public/elfnote: document non-alignment of relocated init-P2M Since PV kernels can't use large pages anyway, when the init-P2M support was added it was decided to keep the implementation simple and not align large pages in PFN space. Document this. Signed-off-by: Jan Beulich Acked-by: Andrew Cooper Release-acked-by: Julien Grall --- xen/include/public/elfnote.h | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/xen/include/public/elfnote.h b/xen/include/public/elfnote.h index 353985fe58..936aa65822 100644 --- a/xen/include/public/elfnote.h +++ b/xen/include/public/elfnote.h @@ -173,7 +173,9 @@ * The (non-default) location the initial phys-to-machine map should be * placed at by the hypervisor (Dom0) or the tools (DomU). * The kernel must be prepared for this mapping to be established using - * large pages, despite such otherwise not being available to guests. + * large pages, despite such otherwise not being available to guests. Note + * that these large pages may be misaligned in PFN space (they'll obviously + * be aligned in MFN and virtual address spaces). * The kernel must also be able to handle the page table pages used for * this mapping not being accessible through the initial mapping. * (Only x86-64 supports this at present.) -- 2.30.2