Re: [PATCH v3 3/3] PCI: dwc: Enable MSI affinity support

[Tsai Sung-Fu]

Hi,

Do we have plan to land this feature upstream ?

Thanks

On Wed, Jan 28, 2026 at 1:09 AM Jon Hunter <jonathanh@xxxxxxxxxx> wrote:
>
> Hi Thomas,
>
> On 27/01/2026 13:34, Thomas Gleixner wrote:
> > On Tue, Jan 27 2026 at 11:30, Thomas Gleixner wrote:
> >> The below untested hack should confirm that theory.
> >
> > Actually looking at it deeper the solution is trivial because in this
> > case writing the MSI message to the device is not required when the
> > affinity changes because the message does not change. It is set once via
> > msi_domain_activate() and stays the same for the life time of the
> > interrupt.
> >
> > So the below prevents the invocation of irq_chip_write_msi_msg() in
> > msi_domain_set_affinity(), but I would recommend to investigate the
> > actual underlying problem nevertheless:
> >
> > It is going to roar its ugly head at some other place sooner than later
> > as there are tons of other places which guard against
> > pci_dev::current_state != PCI_D0.
> >
> > Thanks,
> >
> >          tglx
> > ---
> > --- a/kernel/irq/chip.c
> > +++ b/kernel/irq/chip.c
> > @@ -1495,7 +1495,7 @@ int irq_chip_redirect_set_affinity(struc
> >       WRITE_ONCE(redir->target_cpu, cpumask_first(dest));
> >       irq_data_update_effective_affinity(data, dest);
> >
> > -     return IRQ_SET_MASK_OK;
> > +     return IRQ_SET_MASK_OK_DONE;
> >   }
> >   EXPORT_SYMBOL_GPL(irq_chip_redirect_set_affinity);
> >   #endif
> >
>
> Yes that does fix it!
>
> Tested-by: Jon Hunter <jonathanh@xxxxxxxxxx>
>
> Thanks!
> Jon
>
> --
> nvpublic
>