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authorEduardo Habkost <ehabkost@redhat.com>2008-06-25 04:19:16 (GMT)
committerIngo Molnar <mingo@elte.hu>2008-07-08 11:11:04 (GMT)
commita6523748bddd38bcec11431f57502090b6014a96 (patch)
tree1aa906ba270628323fcdfb26a0ae0f7cfba80ae6 /include
parent491eccb721c2ee67250273a96e4515fb5b423337 (diff)
downloadlinux-fsl-qoriq-a6523748bddd38bcec11431f57502090b6014a96.tar.xz
paravirt/x86, 64-bit: move __PAGE_OFFSET to leave a space for hypervisor
Set __PAGE_OFFSET to the most negative possible address + 16*PGDIR_SIZE. The gap is to allow a space for a hypervisor to fit. The gap is more or less arbitrary, but it's what Xen needs. When booting native, kernel/head_64.S has a set of compile-time generated pagetables used at boot time. This patch removes their absolutely hard-coded layout, and makes it parameterised on __PAGE_OFFSET (and __START_KERNEL_map). Signed-off-by: Eduardo Habkost <ehabkost@redhat.com> Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Cc: xen-devel <xen-devel@lists.xensource.com> Cc: Stephen Tweedie <sct@redhat.com> Cc: Eduardo Habkost <ehabkost@redhat.com> Cc: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'include')
-rw-r--r--include/asm-x86/page_64.h8
1 files changed, 7 insertions, 1 deletions
diff --git a/include/asm-x86/page_64.h b/include/asm-x86/page_64.h
index cac5b9e..010d12d 100644
--- a/include/asm-x86/page_64.h
+++ b/include/asm-x86/page_64.h
@@ -26,7 +26,13 @@
#define PUD_PAGE_SIZE (_AC(1, UL) << PUD_SHIFT)
#define PUD_PAGE_MASK (~(PUD_PAGE_SIZE-1))
-#define __PAGE_OFFSET _AC(0xffff810000000000, UL)
+/*
+ * Set __PAGE_OFFSET to the most negative possible address +
+ * PGDIR_SIZE*16 (pgd slot 272). The gap is to allow a space for a
+ * hypervisor to fit. Choosing 16 slots here is arbitrary, but it's
+ * what Xen requires.
+ */
+#define __PAGE_OFFSET _AC(0xffff880000000000, UL)
#define __PHYSICAL_START CONFIG_PHYSICAL_START
#define __KERNEL_ALIGN 0x200000