Linux Virtualization - Apr 2007 - [PATCH 1/4] Prep for paravirt: move pagetable includes.

Move header includes for the nopud / nopmd types to the location of the
actual pte / pgd type definitions.  This allows generic 4-level page
type code to be written before the split 2/3 level page table headers are
included.

Signed-off-by: Zachary Amsden <zach@vmware.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

==================================================================---
a/include/asm-i386/page.h
+++ b/include/asm-i386/page.h
@@ -52,6 +52,7 @@ typedef struct { unsigned long long pgpr
 #define pte_val(x)	((x).pte_low | ((unsigned long long)(x).pte_high <<
32))
 #define __pmd(x) ((pmd_t) { (x) } )
 #define HPAGE_SHIFT	21
+#include <asm-generic/pgtable-nopud.h>
 #else
 typedef struct { unsigned long pte_low; } pte_t;
 typedef struct { unsigned long pgd; } pgd_t;
@@ -59,6 +60,7 @@ typedef struct { unsigned long pgprot; }
 #define boot_pte_t pte_t /* or would you rather have a typedef */
 #define pte_val(x)	((x).pte_low)
 #define HPAGE_SHIFT	22
+#include <asm-generic/pgtable-nopmd.h>
 #endif
 #define PTE_MASK	PAGE_MASK
 
==================================================================---
a/include/asm-i386/pgtable-2level.h
+++ b/include/asm-i386/pgtable-2level.h
@@ -1,7 +1,5 @@
 #ifndef _I386_PGTABLE_2LEVEL_H
 #define _I386_PGTABLE_2LEVEL_H
-
-#include <asm-generic/pgtable-nopmd.h>
 
 #define pte_ERROR(e) \
 	printk("%s:%d: bad pte %08lx.\n", __FILE__, __LINE__, (e).pte_low)
==================================================================---
a/include/asm-i386/pgtable-3level.h
+++ b/include/asm-i386/pgtable-3level.h
@@ -1,7 +1,5 @@
 #ifndef _I386_PGTABLE_3LEVEL_H
 #define _I386_PGTABLE_3LEVEL_H
-
-#include <asm-generic/pgtable-nopud.h>
 
 /*
  * Intel Physical Address Extension (PAE) Mode - three-level page

(Andrew had already taken that last one, I meant to send this)

Subject: Be careful about touching BIOS address space

BIOS ROM areas may not be mapped into the guest address space, so be careful
when touching those addresses to make sure they appear to be mapped.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

==================================================================---
a/arch/i386/kernel/setup.c
+++ b/arch/i386/kernel/setup.c
@@ -270,7 +270,14 @@ static struct resource standard_io_resou
 	.flags	= IORESOURCE_BUSY | IORESOURCE_IO
 } };
 
-#define romsignature(x) (*(unsigned short *)(x) == 0xaa55)
+static inline int romsignature(const unsigned char *x)
+{
+     unsigned short sig;
+     int ret = 0;
+     if (__get_user(sig, (const unsigned short *)x) == 0)
+	  ret = (sig == 0xaa55);
+     return ret;
+}
 
 static int __init romchecksum(unsigned char *rom, unsigned long length)
 {
==================================================================---
a/arch/i386/pci/pcbios.c
+++ b/arch/i386/pci/pcbios.c
@@ -5,6 +5,7 @@
 #include <linux/pci.h>
 #include <linux/init.h>
 #include <linux/module.h>
+#include <asm/uaccess.h>
 #include "pci.h"
 #include "pci-functions.h"
 
@@ -301,7 +302,7 @@ static struct pci_raw_ops pci_bios_acces
 
 static struct pci_raw_ops * __devinit pci_find_bios(void)
 {
-	union bios32 *check;
+	union bios32 *check, sig;
 	unsigned char sum;
 	int i, length;
 
@@ -314,6 +315,10 @@ static struct pci_raw_ops * __devinit pc
 	for (check = (union bios32 *) __va(0xe0000);
 	     check <= (union bios32 *) __va(0xffff0);
 	     ++check) {
+		long sig;
+		if (__get_user(sig, &check->fields.signature))
+			continue;
+
 		if (check->fields.signature != BIOS32_SIGNATURE)
 			continue;
 		length = check->fields.length * 16;

-- 
 ccontrol: http://ccontrol.ozlabs.org

Rusty Russell wrote:
> Move header includes for the nopud / nopmd types to the location of the
> actual pte / pgd type definitions.  This allows generic 4-level page
> type code to be written before the split 2/3 level page table headers are
> included.
>
> Signed-off-by: Zachary Amsden <zach@vmware.com>
> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
>   
I sent this one out previously .. I think it is already in a subsystem tree.

Zach