There isn't really a way to use an arch-specific get_user_pages_fast in mainline, you'd need to revert the whole series. As a relatively quick workaround you can just remove the select HAVE_FAST_GUP if SPARC64 line from arch/sparc/Kconfig
There isn't really a way to use an arch-specific get_user_pages_fast in mainline, you'd need to revert the whole series. As a relatively quick workaround you can just remove the select HAVE_FAST_GUP if SPARC64 line from arch/sparc/Kconfig