On 10/04/2017 08:59 PM, Pavel Tatashin wrote: > This patch fixes another existing issue on systems that have holes in > zones i.e CONFIG_HOLES_IN_ZONE is defined. > > In for_each_mem_pfn_range() we have code like this: > > if (!pfn_valid_within(pfn) > goto free_range; > > Note: 'page' is not set to NULL and is not incremented but 'pfn' advances. page is initialized to NULL at the beginning of the function. PFN advances but we dont proceed unless pfn_valid_within(pfn) holds true which basically should have checked with arch call back if the PFN is valid in presence of memory holes as well. Is not this correct ? > Thus means if deferred struct pages are enabled on systems with these kind > of holes, linux would get memory corruptions. I have fixed this issue by > defining a new macro that performs all the necessary operations when we > free the current set of pages. If we bail out in case PFN is not valid, then how corruption can happen ? -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>
