On Fri, May 27, 2016 at 7:21 AM, Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> wrote: > hm, this is all ten year old Mel code. > > What's the priority on this? What are the user-visible runtime > effects, how many people are affected, etc? Low priority. To get bitten by this you need to enable a zone that appears after ZONE_MOVABLE in the zone_type enum. As far as I can tell this means running a kernel with ZONE_DEVICE or ZONE_CMA enabled, so I can't see this affecting too many people. I only noticed this because I've been fiddling with ZONE_DEVICE on powerpc and 4.6 broke my test kernel. This bug, in conjunction with the changes in Taku Izumi's kernelcore=mirror patch (d91749c1dda71) and powerpc being the odd architecture which initialises max_zone_pfn[] to ~0ul instead of 0 caused all of system memory to be placed into ZONE_DEVICE at boot, followed a panic since device memory cannot be used for kernel allocations. I've already submitted a patch to fix the powerpc specific bits, but I figured this should be fixed too. oliver -- 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>