On 06/27/2018 09:34 AM, Michal Hocko wrote: > On Tue 26-06-18 10:04:16, Andrew Morton wrote: > > And as I've argued before the code would be wrong regardless. We would > leak the memory or worse touch somebody's else kmap without knowing > that. So we have a choice between a mem leak, data corruption k or a > silent fixup. I would prefer the last option. And blowing up on a BUG > is not much better on something that is easily fixable. I am not really > convinced that & ~__GFP_HIGHMEM is something to lose sleep over. Maybe put the fixup into a "#ifdef CONFIG_HIGHMEM" block and then modern systems won't care? In that case it could even be if (WARN_ON_ONCE(...)) so future cases with wrong expectations would become known. Vlastimil