On Wed 31-07-19 15:42:53, David Hildenbrand wrote: > On 31.07.19 15:25, Michal Hocko wrote: [...] > > I know we have documented this as an ABI and it is really _sad_ that > > this ABI didn't get through normal scrutiny any user visible interface > > should go through but these are sins of the past... > > A quick google search indicates that > > Kata containers queries the block size: > https://github.com/kata-containers/runtime/issues/796 > > Powerpc userspace queries it: > https://groups.google.com/forum/#!msg/powerpc-utils-devel/dKjZCqpTxus/AwkstV2ABwAJ > > I can imagine that ppc dynamic memory onlines only pieces of added > memory - DIMMs AFAIK (haven't looked at the details). > > There might be more users. Thanks! I suspect most of them are just using the information because they do not have anything better. Thinking about it some more, I believe that we can reasonably provide both APIs controlable by a command line parameter for backwards compatibility. It is the hotplug code to control sysfs APIs. E.g. create one sysfs entry per add_memory_resource for the new semantic. It is some time since I've checked the ACPI side of the matter but that code shouldn't really depend on a particular size of the memblock either when trigerring udev events. I might be wrong here of course. -- Michal Hocko SUSE Labs
