On Tue, 14 Dec 2021, Vlastimil Babka wrote: > If doesn't feel right to me to fix (or rather workaround) this on the level > of kmalloc caches just because the current reports come from there. If we > decide it's acceptable for kdump kernel to return !ZONE_DMA memory for > GFP_DMA requests, then it should apply at the page allocator level for all > allocations, not just kmalloc(). > > Also you mention above you'd prefer ZONE_DMA32 memory, while chances are > this approach of using KMALLOC_NORMAL caches will end up giving you > ZONE_NORMAL. On the page allocator level it would be much easier to > implement a fallback from non-populated ZONE_DMA to ZONE_DMA32 specifically. Well this only works if the restrictions on the physical memory addresses of each platform make that possible.
