arm64: Ignore memory blocks below PHYS_OFFSET
According to Documentation/arm64/booting.txt, the kernel image must be
loaded at a pre-defined offset from the start of RAM so that the kernel
can calculate PHYS_OFFSET based on this address. If the DT contains
memory blocks below this PHYS_OFFSET, report them and ignore the
corresponding memory range.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c
index 48ffb9f..7665a9b 100644
--- a/arch/arm64/kernel/setup.c
+++ b/arch/arm64/kernel/setup.c
@@ -170,7 +170,19 @@
void __init early_init_dt_add_memory_arch(u64 base, u64 size)
{
+ base &= PAGE_MASK;
size &= PAGE_MASK;
+ if (base + size < PHYS_OFFSET) {
+ 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);
+ size -= PHYS_OFFSET - base;
+ base = PHYS_OFFSET;
+ }
memblock_add(base, size);
}