Re: RFC on PCI Device Lock

[Alex Williamson <alex.williamson@redhat.com>]

On Tue, 4 Sep 2018 20:41:20 -0700
Sinan Kaya <okaya@kernel.org> wrote:

> On 9/4/2018 8:09 PM, Sinan Kaya wrote:
> > On 9/4/2018 7:46 PM, Alex Williamson wrote:  
> >> #define PCI_RESET_DEV_SPECIFIC    (1 << 0)
> >> #define PCI_RESET_FLR        (1 << 1)
> >> #define PCI_RESET_PM        (1 << 2)
> >> #define PCI_RESET_SLOT        (1 << 3)
> >> #define PCI_RESET_BUS        (1 << 4)
> >>
> >> #define PCI_RESET_ANY        (~0)
> >> #define PCI_RESET_FUNC        (PCI_RESET_DEV_SPECIFIC | \
> >>                  PCI_RESET_FLR | PCI_RESET_PM)
> >> #define PCI_RESET_LINK        (PCI_RESET_SLOT | PCI_RESET_BUS)  
> > 
> > I should be able to put something together using __pci_reset_function_locked()
> > shortly.
> > 
> > This is not that difficult to implement.
> >   
> 
> I posted these
> 
> https://bugzilla.kernel.org/attachment.cgi?id=278297
> https://bugzilla.kernel.org/attachment.cgi?id=278299
> 
> Let me know if I misunderstood you. I'll again wait for test feedback first.

Yep, that's essentially it.  I assume we'd want to trickle this through
other interfaces and the hfi1 folks can look at whether they want to
drop their custom config save/restore in favor of using
pci_reset_function_locked(), which would do that for them.
pci_reset_bus() should also allow the caller to set a mask so vfio
doesn't worry about defaults changing in the core.  Thanks,

Alex