2011-02-12 10:37:06

by Russell King - ARM Linux

Subject: Re: [PATCH v4 17/19] ARM: LPAE: mark memory banks with start > ULONG_MAX as highmem

On Mon, Jan 24, 2011 at 05:55:59PM +0000, Catalin Marinas wrote:
> @@ -782,7 +782,8 @@ static void __init sanity_check_meminfo(void)
>
> #ifdef CONFIG_HIGHMEM
> if (__va(bank->start) > vmalloc_min ||
> - __va(bank->start) < (void *)PAGE_OFFSET)
> + __va(bank->start) < (void *)PAGE_OFFSET ||
> + bank->start > ULONG_MAX)

I think this check should be first, so that we don't try to evaluate __va()
on phys addresses > ULONG_MAX, possibly resulting in truncation.