From: kaf24@firebug.cl.cam.ac.uk <kaf24@firebug.cl.cam.ac.uk>
Date: Wed, 7 Jun 2006 10:24:44 +0000 (+0100)
Subject: x86/64 Linux: destroy entire init memory mapping beyond kernel image.
X-Git-Tag: archive/raspbian/4.8.0-1+rpi1~1^2~15972^2~48
X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=2ad3e284b4cc608c2a5464e04fe95d8f11c6c922;p=xen.git

x86/64 Linux: destroy entire init memory mapping beyond kernel image.
Avoids overlap with modules mapping area.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
---

diff --git a/linux-2.6-xen-sparse/arch/x86_64/kernel/setup-xen.c b/linux-2.6-xen-sparse/arch/x86_64/kernel/setup-xen.c
index e02aba7b34..0b88c1781f 100644
--- a/linux-2.6-xen-sparse/arch/x86_64/kernel/setup-xen.c
+++ b/linux-2.6-xen-sparse/arch/x86_64/kernel/setup-xen.c
@@ -819,14 +819,6 @@ void __init setup_arch(char **cmdline_p)
 #ifdef CONFIG_XEN
 	{
 		int i, j, k, fpp;
-		unsigned long va;
-
-		/* 'Initial mapping' of initrd must be destroyed. */
-		for (va = xen_start_info->mod_start;
-		     va < (xen_start_info->mod_start+xen_start_info->mod_len);
-		     va += PAGE_SIZE) {
-			HYPERVISOR_update_va_mapping(va, __pte_ma(0), 0);
-		}
 
 		if (!xen_feature(XENFEAT_auto_translated_physmap)) {
 			/* Make sure we have a large enough P->M table. */
@@ -842,14 +834,6 @@ void __init setup_arch(char **cmdline_p)
 				PFN_PHYS(PFN_UP(xen_start_info->nr_pages *
 						sizeof(unsigned long))));
 
-			/* Destroyed 'initial mapping' of old p2m table. */
-			for (va = xen_start_info->mfn_list;
-			     va < (xen_start_info->mfn_list +
-				   (xen_start_info->nr_pages*sizeof(unsigned long)));
-			     va += PAGE_SIZE) {
-				HYPERVISOR_update_va_mapping(va, __pte_ma(0), 0);
-			}
-
 			/*
 			 * Initialise the list of the frames that specify the
 			 * list of frames that make up the p2m table. Used by
diff --git a/linux-2.6-xen-sparse/arch/x86_64/mm/init-xen.c b/linux-2.6-xen-sparse/arch/x86_64/mm/init-xen.c
index 3882686049..fe41bfacc3 100644
--- a/linux-2.6-xen-sparse/arch/x86_64/mm/init-xen.c
+++ b/linux-2.6-xen-sparse/arch/x86_64/mm/init-xen.c
@@ -668,12 +668,28 @@ void __meminit init_memory_mapping(unsigned long start, unsigned long end)
 
 	if (!after_bootmem) {
 		BUG_ON(start_pfn != table_end);
-		/*
-		 * Destroy the temporary mappings created above. Prevents
+
+		/* Re-vector virtual addresses pointing into the initial
+		   mapping to the just-established permanent ones. */
+		xen_start_info = __va(__pa(xen_start_info));
+		xen_start_info->pt_base = (unsigned long)
+			__va(__pa(xen_start_info->pt_base));
+		if (!xen_feature(XENFEAT_auto_translated_physmap)) {
+			phys_to_machine_mapping =
+				__va(__pa(xen_start_info->mfn_list));
+			xen_start_info->mfn_list = (unsigned long)
+				phys_to_machine_mapping;
+		}
+		if (xen_start_info->mod_start)
+			xen_start_info->mod_start = (unsigned long)
+				__va(__pa(xen_start_info->mod_start));
+
+		/* Destroy the Xen-created mappings beyond the kernel image as
+		 * well as the temporary mappings created above. Prevents
 		 * overlap with modules area (if init mapping is very big).
 		 */
-		start = __START_KERNEL_map + (table_start << PAGE_SHIFT);
-		end   = __START_KERNEL_map + (table_end   << PAGE_SHIFT);
+		start = PAGE_ALIGN((unsigned long)_end);
+		end   = __START_KERNEL_map + (table_end << PAGE_SHIFT);
 		for (; start < end; start += PAGE_SIZE)
 			WARN_ON(HYPERVISOR_update_va_mapping(
 				start, __pte_ma(0), 0));