ARM: 7864/1: Handle 64-bit memory in case of 32-bit phys_addr_t

Use CONFIG_ARCH_PHYS_ADDR_T_64BIT to determine
if ignoring or truncating of memory banks is
neccessary. This may be needed in the case of
64-bit memory bank addresses but when phys_addr_t
is kept 32-bit.

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 12 insertions, 4 deletions

diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c
index 5ec4443af08b..53c3901f7ee3 100644
--- a/arch/arm/kernel/setup.c
+++ b/arch/arm/kernel/setup.c
@@ -624,6 +624,7 @@ void __init dump_machine_table(void)
 int __init arm_add_memory(u64 start, u64 size)
 {
         struct membank *bank = &meminfo.bank[meminfo.nr_banks];
+        u64 aligned_start;
 
         if (meminfo.nr_banks >= NR_BANKS) {
                 printk(KERN_CRIT "NR_BANKS too low, "
@@ -636,10 +637,16 @@ int __init arm_add_memory(u64 start, u64 size)
          * Size is appropriately rounded down, start is rounded up.
          */
         size -= start & ~PAGE_MASK;
-        bank->start = PAGE_ALIGN(start);
+        aligned_start = PAGE_ALIGN(start);
 
-#ifndef CONFIG_ARM_LPAE
-        if (bank->start + size < bank->start) {
+#ifndef CONFIG_ARCH_PHYS_ADDR_T_64BIT
+        if (aligned_start > ULONG_MAX) {
+                printk(KERN_CRIT "Ignoring memory at 0x%08llx outside "
+                       "32-bit physical address space\n", (long long)start);
+                return -EINVAL;
+        }
+
+        if (aligned_start + size > ULONG_MAX) {
                 printk(KERN_CRIT "Truncating memory at 0x%08llx to fit in "
                         "32-bit physical address space\n", (long long)start);
                 /*
@@ -647,10 +654,11 @@ int __init arm_add_memory(u64 start, u64 size)
                  * 32 bits, we use ULONG_MAX as the upper limit rather than 4GB.
                  * This means we lose a page after masking.
                  */
-                size = ULONG_MAX - bank->start;
+                size = ULONG_MAX - aligned_start;
         }
 #endif
 
+        bank->start = aligned_start;
         bank->size = size & ~(phys_addr_t)(PAGE_SIZE - 1);
 
         /*