[PATCH 3.10 81/85] ARM: 7864/1: Handle 64-bit memory in case of 32-bit phys_addr_t

Greg Kroah-Hartman
2014-03-21T00:23:35Z

From: Magnus Damm <damm@opensource.se>

commit 6d7d5da7d75c6df676c8b72d32b02ff024438f0c upstream.

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>
Cc: Wang Nan <wangnan0@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
arch/arm/kernel/setup.c | 16 ++++++++++++----
1 file changed, 12 insertions(+), 4 deletions(-)

--- a/arch/arm/kernel/setup.c
+++ b/arch/arm/kernel/setup.c
@@ -530,6 +530,7 @@ void __init dump_machine_table(void)
int __init arm_add_memory(phys_addr_t start, phys_addr_t 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, "
@@ -542,10 +543,16 @@ int __init arm_add_memory(phys_addr_t st
* 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);
/*
@@ -553,10 +560,11 @@ int __init arm_add_memory(phys_addr_t st
* 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);

/*