Re: [PATCH AUTOSEL 5.5 23/28] kconfig: Add yes2modconfig and mod2yesconfig targets.

[Tetsuo Handa]

Hello.

I'm fine with backporting this patch. But if you want to backport this patch, please also
backport 089b7d890f972f6b ("kconfig: Invalidate all symbols after changing to y or m.")
which actually makes this patch functional.

On 2020/03/27 8:23, Sasha Levin wrote:
> From: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx>
> 
> [ Upstream commit 89b9060987d988333de59dd218c9666bd7ee95a5 ]
> 
> Since kernel configs provided by syzbot are close to "make allyesconfig",
> it takes long time to rebuild. This is especially waste of time when we
> need to rebuild for many times (e.g. doing manual printk() inspection,
> bisect operations).
> 
> We can save time if we can exclude modules which are irrelevant to each
> problem. But "make localmodconfig" cannot exclude modules which are built
> into vmlinux because /sbin/lsmod output is used as the source of modules.
> 
> Therefore, this patch adds "make yes2modconfig" which converts from =y
> to =m if possible. After confirming that the interested problem is still
> reproducible, we can try "make localmodconfig" (and/or manually tune
> based on "Modules linked in:" line) in order to exclude modules which are
> irrelevant to the interested problem. While we are at it, this patch also
> adds "make mod2yesconfig" which converts from =m to =y in case someone
> wants to convert from =m to =y after "make localmodconfig".
> 
> Signed-off-by: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx>
> Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx>
> Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx>
> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>