Re: [PATCH RESEND] misc: pci_endpoint_test: Defer IRQ allocation until ioctl(PCITEST_SET_IRQTYPE)

[Bjorn Helgaas <helgaas@kernel.org>]

On Wed, Apr 23, 2025 at 02:46:03PM +0200, Niklas Cassel wrote:
> On Tue, Apr 22, 2025 at 12:53:19PM -0500, Bjorn Helgaas wrote:
> > On Sun, Apr 20, 2025 at 09:31:46AM +0530, Manivannan Sadhasivam wrote:
> > > On Wed, 16 Apr 2025 16:28:26 +0200, Niklas Cassel wrote:
> > > > Commit a402006d48a9 ("misc: pci_endpoint_test: Remove global 'irq_type'
> > > > and 'no_msi'") changed so that the default IRQ vector requested by
> > > > pci_endpoint_test_probe() was no longer the module param 'irq_type',
> > > > but instead test->irq_type. test->irq_type is by default
> > > > IRQ_TYPE_UNDEFINED (until someone calls ioctl(PCITEST_SET_IRQTYPE)).
> > > > 
> > > > However, the commit also changed so that after initializing test->irq_type
> > > > to IRQ_TYPE_UNDEFINED, it also overrides it with driver_data->irq_type, if
> > > > the PCI device and vendor ID provides driver_data.
> > > > 
> > > > [...]
> > > 
> > > Applied, thanks!
> > > 
> > > [1/1] misc: pci_endpoint_test: Defer IRQ allocation until ioctl(PCITEST_SET_IRQTYPE)
> > >       commit: 9d564bf7ab67ec326ec047d2d95087d8d888f9b1
> > 
> > a402006d48a9c ("misc: pci_endpoint_test: Remove global 'irq_type' and
> > 'no_msi'") appeared in v6.15-rc1, and apparently caused a regression
> > that some driver fails to probe on such platforms.
> > 
> > Since a402006d48a9c caused a regression and hasn't appeared in a
> > release yet, this sounds like a candidate for v6.15 via pci/for-linus?
> 
> I agree:
> https://lore.kernel.org/linux-pci/Z_0mUhHzGqNrMBGg@ryzen/
> 
> > I can move it if you agree.  I *would* like to have a little more
> > detail about the regression, e.g., the affected driver, so I can
> > justify merging this after the merge window.
> 
> All drivers without any driver_data defined, i.e.:
>         { PCI_DEVICE(PCI_VENDOR_ID_FREESCALE, PCI_DEVICE_ID_IMX8),},
>         { PCI_DEVICE(PCI_VENDOR_ID_RENESAS, PCI_DEVICE_ID_RENESAS_R8A774A1),},
>         { PCI_DEVICE(PCI_VENDOR_ID_RENESAS, PCI_DEVICE_ID_RENESAS_R8A774B1),},
>         { PCI_DEVICE(PCI_VENDOR_ID_RENESAS, PCI_DEVICE_ID_RENESAS_R8A774C0),},
>         { PCI_DEVICE(PCI_VENDOR_ID_RENESAS, PCI_DEVICE_ID_RENESAS_R8A774E1),},
> 
> 
> For those platforms, without this patch, you will get:
>   pci-endpoint-test 0001:01:00.0: Invalid IRQ type selected
>   pci-endpoint-test 0001:01:00.0: probe with driver pci-endpoint-test failed with error -22

So I guess this means it's "only" the host side
pci_endpoint_test_driver that won't probe, and the problem only
happens on the host controllers listed above or controllers with
programmable Vendor/Device ID that are set to match one of these?

I cherry picked this patch to pci/for-linus for v6.15, thanks!

Mani, this was the only patch on pci/misc-endpoint, so I deleted the
branch.

Bjorn