On 18.01.21 14:12, Anshuman Khandual wrote: > This series adds a mechanism allowing platforms to weigh in and prevalidate > incoming address range before proceeding further with the memory hotplug. > This helps prevent potential platform errors for the given address range, > down the hotplug call chain, which inevitably fails the hotplug itself. > > This mechanism was suggested by David Hildenbrand during another discussion > with respect to a memory hotplug fix on arm64 platform. > > https://lore.kernel.org/linux-arm-kernel/1600332402-30123-1-git-send-email-anshuman.khandual@xxxxxxx/ > > This mechanism focuses on the addressibility aspect and not [sub] section > alignment aspect. Hence check_hotplug_memory_range() and check_pfn_span() > have been left unchanged. Wondering if all these can still be unified in > an expanded memhp_range_allowed() check, that can be called from multiple > memory hot add and remove paths. > > This series applies on v5.11-rc4 and has been tested on arm64. But only > build tested on s390. > > Changes in V3 > > - Updated the commit message in [PATCH 1/3] > - Replaced 1 with 'true' and 0 with 'false' in memhp_range_allowed() > - Updated memhp_range.end as VMEM_MAX_PHYS - 1 and updated vmem_add_mapping() on s390 > - Changed memhp_range_allowed() behaviour in __add_pages() > - Updated __add_pages() to return E2BIG when memhp_range_allowed() fails for non-linear mapping based requests Minor thing, we should make up our mind if we want to call stuff internally "memhp_" or "mhp". I prefer the latter, because it is shorter. -- Thanks, David / dhildenb
