Re: [PATCH] PCI Hotplug: fakephp: fix deadlock... again

[Alex Chiang <achiang@hp.com>]

* Matthew Wilcox <matthew@wil.cx>:
> On Mon, Sep 01, 2008 at 12:40:18PM -0600, Alex Chiang wrote:
> > We get the "slot already scheduled for removal" because that
> > particular device has 2 functions, and we're creating slots
> > on a per-slot basis now, not a per-function basis.
> > 
> > Although, I wonder, Willy -- is that really the right thing
> > to do? Seems like fakephp would be more useful if we did
> > operate on a per-function basis, and not per-slot. Especially
> > given Yu's work with SR-IOV, where we can apparently have
> > lots of functions per a physical device.
> 
> I suspect it depends on what you believe the point of fakephp
> is.  

Ok, this was all developed before I started working in this area,
or Linux, even. ;)

> My assumption was that it was a way to fake what would happen
> if you had a hotplug controller for a particular slot.  In that
> context, the change I made was clearly correct.  If you want to
> use it for hot-removing individual functions from a Linux guest
> running under a hypervisor (for example), that's much less
> useful.

Sure, that sounds reasonable.

In that case, my patch should fix the stupid regression I
introduced, but if others think that fakephp would be more useful
for hot-removing functions, I wouldn't object to reverting the
original patch.

Thanks.

/ac