[PATCH v16 9/9] of: fdt: fix memory address be truncated

[Haojian Zhuang]

early_init_dt_add_memory_arch() accepts base & size parameters as u64
type. memblock_add() accepts base & size parameters as phys_addr_t type.
But phys_addr_t isn't equal to u64. In 32-bit system, phys_addr_t is
32-bit long. If 64-bit memory address is specified in DTS file, it'll be
truncated into 32-bit address.

So create two values to store base & size first as phys_addr_t type.
Then compare them with u64 base & u64 size. If they don't match, discard
them.

Signed-off-by: Haojian Zhuang <haojian.zhuang at linaro.org>
---
 drivers/of/fdt.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index c4cddf0..10d5382 100644
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -878,6 +878,8 @@ int __init early_init_dt_scan_chosen(unsigned long node, const char *uname,
 void __init __weak early_init_dt_add_memory_arch(u64 base, u64 size)
 {
 	const u64 phys_offset = __pa(PAGE_OFFSET);
+	phys_addr_t mbase, msize;
+
 	base &= PAGE_MASK;
 	size &= PAGE_MASK;
 	if (base + size < phys_offset) {
@@ -885,6 +887,14 @@ void __init __weak early_init_dt_add_memory_arch(u64 base, u64 size)
 			   base, base + size);
 		return;
 	}
+	/* phys_addr_t may not be equal to u64 */
+	mbase = base;
+	msize = size;
+	if ((mbase != base) || (msize != size)) {
+		pr_warning("Ignoring memory block 0x%llx - 0x%llx\n",
+			   base, base + size);
+		return;
+	}
 	if (base < phys_offset) {
 		pr_warning("Ignoring memory range 0x%llx - 0x%llx\n",
 			   base, phys_offset);
-- 
1.9.1