[PATCH] powerpc: Fixed memory reserve map layout

powerpc: Fixed memory reserve map layout

The memory reserve map is suppose to be a pair of 64-bit integers
to represent each region.  On ppc32 the code was treating the
pair as two 32-bit integers.  Additional the prom_init code was
producing the wrong layout on ppc32.

Added a simple check to try to provide backwards compatibility.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 24 insertions, 4 deletions

diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c
index 34ab0daec3a7..02e2115323e4 100644
--- a/arch/powerpc/kernel/prom.c
+++ b/arch/powerpc/kernel/prom.c
@@ -1100,17 +1100,37 @@ static int __init early_init_dt_scan_memory(unsigned long node,
 
 static void __init early_reserve_mem(void)
 {
-        unsigned long base, size;
-        unsigned long *reserve_map;
+        u64 base, size;
+        u64 *reserve_map;
 
-        reserve_map = (unsigned long *)(((unsigned long)initial_boot_params) +
+        reserve_map = (u64 *)(((unsigned long)initial_boot_params) +
                                         initial_boot_params->off_mem_rsvmap);
+#ifdef CONFIG_PPC32
+        /* 
+         * Handle the case where we might be booting from an old kexec
+         * image that setup the mem_rsvmap as pairs of 32-bit values
+         */
+        if (*reserve_map > 0xffffffffull) {
+                u32 base_32, size_32;
+                u32 *reserve_map_32 = (u32 *)reserve_map;
+
+                while (1) {
+                        base_32 = *(reserve_map_32++);
+                        size_32 = *(reserve_map_32++);
+                        if (size_32 == 0)
+                                break;
+                        DBG("reserving: %lx -> %lx\n", base_32, size_32);
+                        lmb_reserve(base_32, size_32);
+                }
+                return;
+        }
+#endif
         while (1) {
                 base = *(reserve_map++);
                 size = *(reserve_map++);
                 if (size == 0)
                         break;
-                DBG("reserving: %lx -> %lx\n", base, size);
+                DBG("reserving: %llx -> %llx\n", base, size);
                 lmb_reserve(base, size);
         }