x86, ramdisk: Export relocated ramdisk VA

The ramdisk can possibly get relocated if the whole image is not mapped.
And since we're going over it in the microcode loader and fishing out
the relevant microcode patches, we want access it at its new location.
Thus, export it.

Signed-off-by: Borislav Petkov <bp@suse.de>
Tested-by: Aravind Gopalakrishnan <Aravind.Gopalakrishnan@amd.com>

arch/x86/include/asm/setup.h

@@ -3,7 +3,6 @@
 
 #include <uapi/asm/setup.h>
 
-
 #define COMMAND_LINE_SIZE 2048
 
 #include <linux/linkage.h>
@@ -29,6 +28,8 @@
 #include <asm/bootparam.h>
 #include <asm/x86_init.h>
 
+extern u64 relocated_ramdisk;
+
 /* Interrupt control for vSMPowered x86_64 systems */
 #ifdef CONFIG_X86_64
 void vsmp_init(void);

arch/x86/kernel/setup.c

@@ -295,6 +295,8 @@ static void __init reserve_brk(void)
 	_brk_start = 0;
 }
 
+u64 relocated_ramdisk;
+
 #ifdef CONFIG_BLK_DEV_INITRD
 
 static u64 __init get_ramdisk_image(void)
@@ -321,25 +323,24 @@ static void __init relocate_initrd(void)
 	u64 ramdisk_image = get_ramdisk_image();
 	u64 ramdisk_size  = get_ramdisk_size();
 	u64 area_size     = PAGE_ALIGN(ramdisk_size);
-	u64 ramdisk_here;
 	unsigned long slop, clen, mapaddr;
 	char *p, *q;
 
 	/* We need to move the initrd down into directly mapped mem */
-	ramdisk_here = memblock_find_in_range(0, PFN_PHYS(max_pfn_mapped),
-						 area_size, PAGE_SIZE);
+	relocated_ramdisk = memblock_find_in_range(0, PFN_PHYS(max_pfn_mapped),
+						   area_size, PAGE_SIZE);
 
-	if (!ramdisk_here)
+	if (!relocated_ramdisk)
 		panic("Cannot find place for new RAMDISK of size %lld\n",
-			 ramdisk_size);
+		      ramdisk_size);
 
 	/* Note: this includes all the mem currently occupied by
 	   the initrd, we rely on that fact to keep the data intact. */
-	memblock_reserve(ramdisk_here, area_size);
-	initrd_start = ramdisk_here + PAGE_OFFSET;
+	memblock_reserve(relocated_ramdisk, area_size);
+	initrd_start = relocated_ramdisk + PAGE_OFFSET;
 	initrd_end   = initrd_start + ramdisk_size;
 	printk(KERN_INFO "Allocated new RAMDISK: [mem %#010llx-%#010llx]\n",
-			 ramdisk_here, ramdisk_here + ramdisk_size - 1);
+	       relocated_ramdisk, relocated_ramdisk + ramdisk_size - 1);
 
 	q = (char *)initrd_start;
 
@@ -363,7 +364,7 @@ static void __init relocate_initrd(void)
 	printk(KERN_INFO "Move RAMDISK from [mem %#010llx-%#010llx] to"
 		" [mem %#010llx-%#010llx]\n",
 		ramdisk_image, ramdisk_image + ramdisk_size - 1,
-		ramdisk_here, ramdisk_here + ramdisk_size - 1);
+		relocated_ramdisk, relocated_ramdisk + ramdisk_size - 1);
 }
 
 static void __init early_reserve_initrd(void)