On Wed, Sep 26, 2018 at 11:25:37AM -0700, Alexander Duyck wrote: > With that said I am open to suggestions if you still feel like I need to > follow this up with some additional work. I just want to avoid introducing > any regressions in regards to functionality or performance. Hi Alexander, the problem I see is that devm/hmm is using some of the memory-hotplug features, but their paths are becoming more and more diverged with changes like this, and that is sometimes a problem when we need to change something in the generic memory-hotplug code. E.g: I am trying to fix two issues in the memory-hotplug where we can access steal pages if we hot-remove memory before online it. That was not so difficult to fix, but I really struggled with the exceptions that HMM/devm represent in this regard, for instance, regarding the resources. The RFCv2 can be found here [1] https://patchwork.kernel.org/patch/10569083/ And the initial discussion with Jerome Glisse can be found here [2]. So it would be great to stick to the memory-hotplug path as much as possible, otherwise when a problem arises, we need to think how we can workaround HMM/devm. [1] https://patchwork.kernel.org/patch/10569083/ [2] https://patchwork.kernel.org/patch/10558725/ -- Oscar Salvador SUSE L3
