On Mon, Mar 11, 2019 at 05:28:15PM +0100, Ralph Seichter wrote:
> * John Stoffel:
> > And we're going to run into this exact same problem the next time
> > Linus bumps the major version
> Looking at the Linux Kernel development history, you see that major
> versions have been released years apart. Version 5 has only just
> arrived.
The large problem is, that on Linux the version of the kernel only
defines the kernel interface. It however does not show if the libc for
userspace contains a syscal wrapper to make it usable. You can upgrade
one without the other for a wide variety of combinations. There are
even multiple libc implementations available.
This is different to all the BSD, where kernel and libc are defined as
one unit and need to be updated in particular order to not break stuff.
Let's assume you are running Linux 5.0 with glibc 2.2. Linux 5.0
support epoll_create, glibc 2.2 does not contain a syscall wrapper, so
it is not usable from userspace. What will you do?
> > Maybe it's make more sense to assume that all new releases are
> > compatible, and only add in a nother switch statement when you know
> > there's an issue?
> Personally, I prefer Wietse to run QA and change the build when he is
> satisfied things are working. You can always make local changes if you
> are in a hurry, some years down the road. ;-)
QA for what? QA that the libc interface did not change suddenly?
Bastian
--
Four thousand throats may be cut in one night by a running man.
-- Klingon Soldier, "Day of the Dove", stardate unknown
