From mboxrd@z Thu Jan 1 00:00:00 1970 From: catalin.marinas@arm.com (Catalin Marinas) Date: Tue, 16 Oct 2012 17:46:39 +0100 Subject: [PATCH 3/4] arm64: Ignore memory blocks below PHYS_OFFSET In-Reply-To: <1350406000-30882-1-git-send-email-catalin.marinas@arm.com> References: <1350406000-30882-1-git-send-email-catalin.marinas@arm.com> Message-ID: <1350406000-30882-4-git-send-email-catalin.marinas@arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org 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 --- arch/arm64/kernel/setup.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) 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 @@ static void __init setup_machine_fdt(phys_addr_t dt_phys) 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); }