From 965194c15dc9e4f3bc44432b39c441c86af7f11d Mon Sep 17 00:00:00 2001
From: Yinghai Lu <yhlu.kernel@gmail.com>
Date: Sat, 12 Jul 2008 14:31:28 -0700
Subject: x86: max_low_pfn_mapped fix, #2

tighten the boundary checks around max_low_pfn_mapped - dont overmap
nor undermap into holes.

also print out tseg for AMD cpus, for diagnostic purposes.
(this is an SMM area, and we split up any big mappings around that area)

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/arch/x86/kernel/cpu/amd_64.c b/arch/x86/kernel/cpu/amd_64.c
index bd182b76..7c36fb8 100644
--- a/arch/x86/kernel/cpu/amd_64.c
+++ b/arch/x86/kernel/cpu/amd_64.c
@@ -200,6 +200,7 @@ static void __cpuinit init_amd(struct cpuinfo_x86 *c)
 		 * benefit in doing so.
 		 */
 		if (!rdmsrl_safe(MSR_K8_TSEG_ADDR, &tseg)) {
+		    printk(KERN_DEBUG "tseg: %010llx\n", tseg);
 		    if ((tseg>>PMD_SHIFT) <
 				(max_low_pfn_mapped>>(PMD_SHIFT-PAGE_SHIFT)) ||
 			((tseg>>PMD_SHIFT) <
diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
index 0389cb8..fb6f2ab 100644
--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -658,11 +658,11 @@ static int cpa_process_alias(struct cpa_data *cpa)
 	struct cpa_data alias_cpa;
 	int ret = 0;
 
-	if (cpa->pfn > max_pfn_mapped)
+	if (cpa->pfn >= max_pfn_mapped)
 		return 0;
 
 #ifdef CONFIG_X86_64
-	if (cpa->pfn > max_low_pfn_mapped && cpa->pfn < (1UL<<(32-PAGE_SHIFT)))
+	if (cpa->pfn >= max_low_pfn_mapped && cpa->pfn < (1UL<<(32-PAGE_SHIFT)))
 		return 0;
 #endif
 	/*
diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c
index 749766c3..d458507 100644
--- a/arch/x86/mm/pat.c
+++ b/arch/x86/mm/pat.c
@@ -449,8 +449,8 @@ int phys_mem_access_prot_allowed(struct file *file, unsigned long pfn,
 	if (retval < 0)
 		return 0;
 
-	if (((pfn <= max_low_pfn_mapped) ||
-	     (pfn >= (1UL<<(32 - PAGE_SHIFT)) && pfn <= max_pfn_mapped)) &&
+	if (((pfn < max_low_pfn_mapped) ||
+	     (pfn >= (1UL<<(32 - PAGE_SHIFT)) && pfn < max_pfn_mapped)) &&
 	    ioremap_change_attr((unsigned long)__va(offset), size, flags) < 0) {
 		free_memtype(offset, offset + size);
 		printk(KERN_INFO
diff --git a/arch/x86/pci/i386.c b/arch/x86/pci/i386.c
index 5281e34..2aafb67 100644
--- a/arch/x86/pci/i386.c
+++ b/arch/x86/pci/i386.c
@@ -334,9 +334,9 @@ int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma,
 		flags = new_flags;
 	}
 
-	if (((vma->vm_pgoff <= max_low_pfn_mapped) ||
+	if (((vma->vm_pgoff < max_low_pfn_mapped) ||
 	     (vma->vm_pgoff >= (1UL<<(32 - PAGE_SHIFT)) &&
-	      vma->vm_pgoff <= max_pfn_mapped)) &&
+	      vma->vm_pgoff < max_pfn_mapped)) &&
 	    ioremap_change_attr((unsigned long)__va(addr), len, flags)) {
 		free_memtype(addr, addr + len);
 		return -EINVAL;
-- 
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