Re: Linux 4.9.256

From: Greg Kroah-Hartman
Date: Mon Feb 08 2021 - 13:39:24 EST


On Mon, Feb 08, 2021 at 05:50:21PM +0200, Avi Kivity wrote:
> On 05/02/2021 16.26, Greg Kroah-Hartman wrote:
> > I'm announcing the release of the 4.9.256 kernel.
> >
> > This, and the 4.4.256 release are a little bit "different" than normal.
> >
> > This contains only 1 patch, just the version bump from .255 to .256 which ends
> > up causing the userspace-visable LINUX_VERSION_CODE to behave a bit differently
> > than normal due to the "overflow".
> >
> > With this release, KERNEL_VERSION(4, 9, 256) is the same as KERNEL_VERSION(4, 10, 0).
>
>
> I think this is a bad idea. Many kernel features can only be discovered by
> checking the kernel version. If a feature was introduced in 4.10, then an
> application can be tricked into thinking a 4.9 kernel has it.
>
>
> IMO, better to stop LINUX_VERSION_CODE at 255 and introduce a
> LINUX_VERSION_CODE_IMPROVED that has more bits for patchlevel.

We are going to stop LINUX_VERSION_CODE at 255 now, see the posted
patches from Sasha, I think we are now ok.

thanks,

greg k-h