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 z9MVXXZd 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because that hides everything. vfio_device still needs it. > > So, we have two ops that need to be touched to support this: > > vfio_device_fops > vfio_pci_ops > > For the 1st one's vfio_device_fops.get_unmapped_area(), it'll need its own > fallback which must be mm_get_unmapped_area() to keep the old behavior, and > that was defined only if CONFIG_MMU. OK, CONFIG_MMU makes a little bit of sense > IOW, if one day file_operations.get_unmapped_area() would allow some other > retval to be able to fallback to the default (mm_get_unmapped_area()), then > we don't need this special ifdef. But now it's not ready for that.. That can't be fixed with a config, the logic in vfio_device_fops has to be if (!device->ops->get_unmapped_area() return .. do_default thing.. return device->ops->get_unmapped() Has nothing to do with CONFIG_ARCH_SUPPORTS_HUGE_PFNMAP, there are more device->ops that just PCI. If you do the API with an align/order argument then the default behavior should happen when passing PAGE_SIZE. Jason