to workaround wrong BIOS memory map.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
arch/x86/kernel/e820.c | 44 ++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 44 insertions(+), 0 deletions(-)
diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c
index 14d0a1a..73dc6a7 100644
--- a/arch/x86/kernel/e820.c
+++ b/arch/x86/kernel/e820.c
@@ -1044,6 +1044,47 @@ static int __init parse_memmap_opt(char *p)
}
early_param("memmap", parse_memmap_opt);
+static void __init e820_align_ram_page(void)
+{
+ int i;
+ bool changed = false;;
+
+ for (i = 0; i < e820.nr_map; i++) {
+ struct e820entry *entry = &e820.map[i];
+ u64 start, end;
+ u64 start_aligned, end_aligned;
+
+ if (entry->type != E820_RAM)
+ continue;
+
+ start = entry->addr;
+ end = start + entry->size;
+
+ start_aligned = round_up(start, PAGE_SIZE);
+ end_aligned = round_down(end, PAGE_SIZE);
+
+ if (end_aligned <= start_aligned) {
+ e820_update_range(start, end - start, E820_RAM, E820_RESERVED);
+ changed = true;
+ continue;
+ }
+ if (start < start_aligned) {
+ e820_update_range(start, start_aligned - start, E820_RAM, E820_RESERVED);
+ changed = true;
+ }
+ if (end_aligned < end) {
+ e820_update_range(end_aligned, end - end_aligned, E820_RAM, E820_RESERVED);
+ changed = true;
+ }
+ }
+
+ if (changed) {
+ sanitize_e820_map();
+ printk(KERN_INFO "aligned physical RAM map:\n");
+ e820_print_map("aligned");
+ }
+}
+
void __init finish_e820_parsing(void)
{
if (userdef) {
@@ -1056,6 +1097,9 @@ void __init finish_e820_parsing(void)
printk(KERN_INFO "user-defined physical RAM map:\n");
e820_print_map("user");
}
+
+ /* In case, We have RAM entres that are not PAGE aligned */
+ e820_align_ram_page();
}
static inline const char *e820_type_to_string(int e820_type)
--
1.6.4.2
--
