Re: [GIT PULL] SCSI fixes for 2.6.32-rc3

Ingo Molnar
2009-10-12T13:06:52Z

* James Bottomley <James.Bottomley@suse.de> wrote:

> On Fri, 2009-10-09 at 11:15 +0200, Ingo Molnar wrote:
> > * Linus Torvalds <torvalds@linux-foundation.org> wrote:
> >
> > > On Thu, 8 Oct 2009, Theodore Tso wrote:
> > > >
> > > > So would it be acceptable to merge the 50 kloc of crap _during_ the
> > > > merge window?
> > >
> > > Yes. I actually looked at the driver (since I had pulled it - I've
> > > unpulled it but am still mulling it over), and while I think it looked
> > > huge and overly complex, it by no means gave me the kinds of vibes I
> > > get from some "obviously-ported-from-windows-with-no-clue" drivers.
> > >
> > > So at least from my quick look I didn't get the feeling that the
> > > driver was "evil". For me, it's a timing issue. I hate getting big
> > > pull requests after -rc1 is out, and I really don't like the feeling
> > > that people are just ignoring the merge window.
> > >
> > > That said, if somebody wants to look more closely at the driver, and
> > > then wants to convince people that it should have gone through
> > > "staging", feel free. But that's not what I've personally been arguing
> > > about.
> >
> > Greg, what's your take on the quality of this new driver? Do you have
> > some time to do a review of this with drivers/staging/ versus drivers/
> > glasses on? The Git URI is at:
>
> To me, the matter of staging versus actual tree isn't a quality issue
> (otherwise we'd be shifting ~75% of SCSI drivers to staging, depending
> on whose view of "quality" was being used). [...]

I think you need to update your notion of what goes into
drivers/staging/ - these days it's primarily about code/implementation
quality (Greg please correct me if i'm wrong about that).

Driver ABIs are distinctly down the priority list.

> [...] It's an ABI issue. If we would have to change the user visible
> ABI while the driver was being cleaned up, I'd want it in staging to
> warn users to expect these problems. Although we couldn't clean up
> everything, I did make sure this driver plugs correctly into the
> standard linux FC ABI before putting it in the SCSI tree, so there are
> no ABI changes anticipated even though there will likely be a lot of
> code changes. Therefore, the correct clean up path for this one is
> through the SCSI tree.

What kind of significant ABI does this driver expose? If this question
even comes up then it's using the wrong kind of ABI i think. Drivers
should almost never expose significant new ABIs.

If it's a storage management ABI then that should have been done at a
higher level - possibly as a system call, but at minimum as a general
facility.

(Anyway ... this cannot be argued without knowing what specific ABI you
mean here.)

Ingo