[PATCH 0/4] Patches for -next

[Russell King - ARM Linux]

On Wed, May 26, 2010 at 02:06:35PM +0100, Catalin Marinas wrote:
> +#ifdef CONFIG_SMP
> +void __sync_icache_dcache(pte_t pteval)
> +{
> +	struct page *page = pte_page(pteval);
> +	struct address_space *mapping = page_mapping(page);

Err. no.  You're assuming that the physical page associated with the
PTE always has a struct page.  What if it's a device mapping?  What
if it's a mapping for some memory which isn't being handled by the
kernel?

You want this to be:

	unsigned long pfn = pte_pfn(pteval);

	if (pfn_valid(pfn)) {
		struct page *page = pfn_to_page(pfn);
		struct address_space *mapping = page_mapping(page);