Hi Andrew, On Tue, Feb 11, 2020 at 7:30 AM Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> wrote: > > On Tue, 11 Feb 2020 02:54:52 +0900 Masahiro Yamada <masahiroy@xxxxxxxxxx> wrote: > > > Change a header to mandatory-y if both of the following are met: > > > > [1] At least one architecture (except um) specifies it as generic-y in > > arch/*/include/asm/Kbuild > > > > [2] Every architecture (except um) either has its own implementation > > (arch/*/include/asm/*.h) or specifies it as generic-y in > > arch/*/include/asm/Kbuild > > (reads Documentation/kbuild/makefiles.rst to remember what these things > do). > > Why are we making this change? What's the benefit? One obvious benefit is the diff stat: 25 files changed, 52 insertions(+), 557 deletions(-) It is tedious to list generic-y for each arch that needs it. So, mandatory-y works like a fallback default (by just wrapping asm-generic one) when arch does not have a specific header implementation. See the following commits: def3f7cefe4e81c296090e1722a76551142c227c a1b39bae16a62ce4aae02d958224f19316d98b24 It is tedious to convert headers one by one, so I processed by a shell script. -- Best Regards Masahiro Yamada