Re: [PATCH 3/3] kbuild: introduce KERNEL_VERSION2 and LINUX_VERSION_CODE2

From: Greg KH
Date: Sat Feb 06 2021 - 07:53:53 EST


On Fri, Feb 05, 2021 at 10:50:33PM -0500, Sasha Levin wrote:
> SUBLEVEL only has 8 bits of space, which means that we'll overflow it
> once it reaches 256.
>
> Few of the stable branches will imminently overflow SUBLEVEL while
> there's no risk of overflowing VERSION.
>
> Thus, give SUBLEVEL 8 more bits which will be stolen from VERSION, this
> should create a better balance between the different version numbers we
> use.
>
> We can't however use the original KERNEL_VERSION and LINUX_VERSION_CODE
> as userspace has created ABI dependency on their structure, and we risk
> breaking this userspace by modifying the layout of the version integers.
>
> Cc: stable@xxxxxxxxxx
> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
> Reviewed-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx>
> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

Reviewed-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>