Re: [Regression] Changes to i2c-piix4.c initialisation prevent loading of sp5100_tco watchdog driver on AMD SB800 chipset

[Guenter Roeck]

On 04/01/2017 03:13 AM, Boszormenyi Zoltan wrote:
> 2017-03-31 17:05 keltezÃssel, Guenter Roeck Ãrta:
> > On Fri, Mar 31, 2017 at 04:46:02PM +0200, Boszormenyi Zoltan wrote:
> > > 2017-03-31 14:49 keltezÃssel, Guenter Roeck Ãrta:
> > > > request_muxed_region() can fail, and literally every other driver
> > > > using it checks for that failure. Please do the same.
> > >
> > > In what circumstances can request_muxed_region() fail? As far as
> > > I can see, only if two drivers use the same I/O port base and the
> > > already present region did not use IORESOURCE_MUXED which is
> > > not the case here. When request_muxed_region() is used consistently,
> > > subsequent requests are put on a wait queue and the first one is
> > > woken up when the region is released. So, it's basically a mutex.
> > > Am I missing something here?
> >
> > Yes. failure to allocate the resource is one.
>
> So, a common mutex should be used.

Just because you don't want to check for errors ?

I am not on favor of your new solution. I think it violates layering all over
the place, and I dislike the idea of having a global mutex as you propose.
I won't shut it down, but I'll let others provide feedback on your new series
of patches.

Guenter

> I have also added synchronization to the USB PCI quirks code and
> have split the patch into three pieces now (USB quirks, i2c-piix4 and
> sp5100_tco) and they were sent to the relevant mailing lists.
>
> I don't know which subsystem wants to take it, all 3 patches are
> needed at once.
>
> Best regards,
> ZoltÃn BÃszÃrmÃnyi