x86: handle initrd that extends into unusable memory

On a system where system memory (according e820) is not covered by
mtrr, mtrr_trim_memory converts a portion of memory to reserved, but
bootloader has already put the initrd in that range.

Thus, we need to have 64bit to use relocate_initrd too.

[ Impact: fix using initrd when mtrr_trim_memory happen ]

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: stable@kernel.org

1 files changed, 3 insertions, 12 deletions

diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index d1c636bf31a7..be5ae80f897f 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -301,15 +301,13 @@ static void __init reserve_brk(void)
 
 #ifdef CONFIG_BLK_DEV_INITRD
 
-#ifdef CONFIG_X86_32
-
 #define MAX_MAP_CHUNK   (NR_FIX_BTMAPS << PAGE_SHIFT)
 static void __init relocate_initrd(void)
 {
 
         u64 ramdisk_image = boot_params.hdr.ramdisk_image;
         u64 ramdisk_size  = boot_params.hdr.ramdisk_size;
-        u64 end_of_lowmem = max_low_pfn << PAGE_SHIFT;
+        u64 end_of_lowmem = max_low_pfn_mapped << PAGE_SHIFT;
         u64 ramdisk_here;
         unsigned long slop, clen, mapaddr;
         char *p, *q;
@@ -365,14 +363,13 @@ static void __init relocate_initrd(void)
                 ramdisk_image, ramdisk_image + ramdisk_size - 1,
                 ramdisk_here, ramdisk_here + ramdisk_size - 1);
 }
-#endif
 
 static void __init reserve_initrd(void)
 {
         u64 ramdisk_image = boot_params.hdr.ramdisk_image;
         u64 ramdisk_size  = boot_params.hdr.ramdisk_size;
         u64 ramdisk_end   = ramdisk_image + ramdisk_size;
-        u64 end_of_lowmem = max_low_pfn << PAGE_SHIFT;
+        u64 end_of_lowmem = max_low_pfn_mapped << PAGE_SHIFT;
 
         if (!boot_params.hdr.type_of_loader ||
             !ramdisk_image || !ramdisk_size)
@@ -402,14 +399,8 @@ static void __init reserve_initrd(void)
                 return;
         }
 
-#ifdef CONFIG_X86_32
         relocate_initrd();
-#else
-        printk(KERN_ERR "initrd extends beyond end of memory "
-               "(0x%08llx > 0x%08llx)\ndisabling initrd\n",
-               ramdisk_end, end_of_lowmem);
-        initrd_start = 0;
-#endif
+
         free_early(ramdisk_image, ramdisk_end);
 }
 #else