Re: [S390] cio: fix stsch_reset.

[Michael Holzheu <HOLZHEU@de.ibm.com>]

heicars2@linux.vnet.ibm.com wrote on 12/31/2006 01:22:03 PM:

> On Sun, Dec 31, 2006 at 01:31:43AM -0500, Chuck Ebbert wrote:
> > In-Reply-To: <20061228103925.GB6270@skybase>
> >
> > On Thu, 28 Dec 2006 11:39:25 +0100, Martin Schwidefsky wrote:
> >
> > > @@ -881,10 +880,18 @@ static void cio_reset_pgm_check_handler(
> > >  static int stsch_reset(struct subchannel_id schid, volatile
> struct schib *addr)
> > >  {
> > >       int rc;
> > > +     register struct subchannel_id reg1 asm ("1") = schid;
> > >
> > >       pgm_check_occured = 0;
> > >       s390_reset_pgm_handler = cio_reset_pgm_check_handler;
> > > -     rc = stsch(schid, addr);
> > > +
> > > +     asm volatile(
> > > +             "       stsch   0(%2)\n"
> > > +             "       ipm     %0\n"
> > > +             "       srl     %0,28"
> > > +             : "=d" (rc)
> > > +             : "d" (reg1), "a" (addr), "m" (*addr) : "memory",
"cc");
> > > +
> > >       s390_reset_pgm_handler = NULL;
> > >       if (pgm_check_occured)
> > >               return -EIO;
> >
> >
> > Can't you just put a barrier() before the stsch() call?
>
> Yes, that would work too and would look much nicer.
>
> I think we should change the reset program check handler, so that it
searches
> the exception tables.

I think that this is really overkill, since having program checks in the
reset case will be VERY rare and stsch will probably the only case.
I would do that only, if we have a component, which needs that.

And I assume, that this will never happen!

Michael


-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/