From 571b14375019c3a66ef70d4d4a7083f4238aca30 Mon Sep 17 00:00:00 2001 From: Russell King Date: Sat, 11 Jan 2014 11:22:18 +0000 Subject: [PATCH] ARM: ignore memory below PHYS_OFFSET If the kernel is loaded higher in physical memory than normal, and we calculate PHYS_OFFSET higher than the start of RAM, this leads to boot problems as we attempt to map part of this RAM into userspace. Rather than struggle with this, just truncate the mapping. Signed-off-by: Russell King --- arch/arm/kernel/setup.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c index 7a2dd46..061cea8 100644 --- a/arch/arm/kernel/setup.c +++ b/arch/arm/kernel/setup.c @@ -660,6 +660,20 @@ int __init arm_add_memory(u64 start, u64 size) } #endif + if (aligned_start < PHYS_OFFSET) { + if (aligned_start + size <= PHYS_OFFSET) { + pr_info("Ignoring memory below PHYS_OFFSET: 0x%08llx-0x%08llx\n", + aligned_start, aligned_start + size); + return -EINVAL; + } + + pr_info("Ignoring memory below PHYS_OFFSET: 0x%08llx-0x%08llx\n", + aligned_start, (u64)PHYS_OFFSET); + + size -= PHYS_OFFSET - aligned_start; + aligned_start = PHYS_OFFSET; + } + bank->start = aligned_start; bank->size = size & ~(phys_addr_t)(PAGE_SIZE - 1); -- 2.7.4