Hi, this is the second version of the series. v1 was posted [1]. There are no functional changes since v1. I have just fixed up the changelog of patch 1 which had a wrong trace (c&p mistake). I have also added tested-bys and reviewed-bys. Mikhail has posted fixes for the two bugs quite some time ago [2]. I have pushed back on those fixes because I believed that it is much better to plug the problem at the initialization time rather than play whack-a-mole all over the hotplug code and find all the places which expect the full memory section to be initialized. We have ended up with 2830bf6f05fb ("mm, memory_hotplug: initialize struct pages for the full memory section") merged and cause a regression [3][4]. The reason is that there might be memory layouts when two NUMA nodes share the same memory section so the merged fix is simply incorrect. In order to plug this hole we really have to be zone range aware in those handlers. I have split up the original patch into two. One is unchanged (patch 2) and I took a different approach for `removable' crash. It would be great if Mikhail could test it still works for his memory layout. [1] http://lkml.kernel.org/r/20190128144506.15603-1-mhocko@xxxxxxxxxx [2] http://lkml.kernel.org/r/20181105150401.97287-2-zaslonko@xxxxxxxxxxxxx [3] https://bugzilla.redhat.com/show_bug.cgi?id=1666948 [4] http://lkml.kernel.org/r/20190125163938.GA20411@xxxxxxxxxxxxxx