Re: [RFC][PATCH] PCI: rcar-gen4: Add missing PM ops

[Marek Vasut]

On 9/7/26 3:46 PM, Koichiro Den wrote:

Hello Den-san,

> I have reproduced the NULL pointer dereference at pci->pp.ops->deinit on R-Car
> S4 Spider in EP mode with CONFIG_PCIE_DW_HOST=y.
>
> (I used next-20260904 with this patch and the following fix applied:
>   "buffer: fix NULL dereference of bh->b_folio in __bh_submit()")

[...]

>      [drivers/pci/controller/dwc/pcie-designware-host.c]
>      1225 int dw_pcie_suspend_noirq(struct dw_pcie *pci)
>      1226 {
>      ...
>      1286         pci->pp.skip_pwrctrl_off = pme_capable;
>      1287         dw_pcie_stop_link(pci);
>    > 1288         if (pci->pp.ops->deinit)
>      1289                 pci->pp.ops->deinit(&pci->pp);
>      1290

Thank you for your help with the endpoint part.

The fix turns out to be very simple -- the suspend/resume handling is 
specific to the PCIe controller in RC mode, so I added a conditional to 
invoke those host (RC) suspend/resume operations only if the controller 
is in that mode, and I sent a V2.

This RC-only fix in V2 is also in line with what MX6 and DRA7xx PCIe 
controllers do.

--
Best regards,
Marek Vasut