3.5.7u1 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Jacob Shin <[email protected]>

commit 1bbbbe779aabe1f0768c2bf8f8c0a5583679b54a upstream.

On systems with very large memory (1 TB in our case), BIOS may report a
reserved region or a hole in the E820 map, even above the 4 GB range. Exclude
these from the direct mapping.

[ hpa: this should be done not just for > 4 GB but for everything above the 
legacy
  region (1 MB), at the very least.  That, however, turns out to require 
significant
  restructuring.  That work is well underway, but is not suitable for 
rc/stable. ]

Signed-off-by: Jacob Shin <[email protected]>
Link: 
http://lkml.kernel.org/r/[email protected]
Signed-off-by: H. Peter Anvin <[email protected]>
Signed-off-by: Herton Ronaldo Krzesinski <[email protected]>
---
 arch/x86/kernel/setup.c |   17 +++++++++++++++--
 1 file changed, 15 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 16be6dc..e615c31 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -919,8 +919,21 @@ void __init setup_arch(char **cmdline_p)
 
 #ifdef CONFIG_X86_64
        if (max_pfn > max_low_pfn) {
-               max_pfn_mapped = init_memory_mapping(1UL<<32,
-                                                    max_pfn<<PAGE_SHIFT);
+               int i;
+               for (i = 0; i < e820.nr_map; i++) {
+                       struct e820entry *ei = &e820.map[i];
+
+                       if (ei->addr + ei->size <= 1UL << 32)
+                               continue;
+
+                       if (ei->type == E820_RESERVED)
+                               continue;
+
+                       max_pfn_mapped = init_memory_mapping(
+                               ei->addr < 1UL << 32 ? 1UL << 32 : ei->addr,
+                               ei->addr + ei->size);
+               }
+
                /* can we preseve max_low_pfn ?*/
                max_low_pfn = max_pfn;
        }
-- 
1.7.9.5

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