RE: [bug report] nvme not re-recognize when changed M.2 SSD in S3 mode

[Ricky WU <ricky_wu@xxxxxxxxxxx>]

Hi Lukas,

I tested this patch and the result looks good, but if the two SSD has same VID, PID and capacity it still has problem.
So I think add S/N to compare is necessary if it can do

And I also tested SD7.0 card the result is same with M.2 SSD

> > --- a/drivers/pci/hotplug/pciehp_core.c
> > +++ b/drivers/pci/hotplug/pciehp_core.c
> > @@ -152,6 +152,25 @@ static int get_adapter_status(struct hotplug_slot
> *hotplug_slot, u8 *value)
> >       return 0;
> >  }
> >
> > +static bool pciehp_device_replaced(struct controller *ctrl) {
> > +     struct pci_dev *pdev;
> 
> I've realized this needs to be
> 
> +       struct pci_dev *pdev __free(pci_dev_put);
> 
> to avoid leaking a ref on the child device.  For testing purposes, the patch
> should still be fine without this change, but I'll have to fix this up if/when
> submitting a proper patch.
> 
> > +     u32 reg;
> > +
> > +     pdev = pci_get_slot(ctrl->pcie->port->subordinate, PCI_DEVFN(0, 0));
> > +     if (!pdev)
> > +             return true;
> > +
> > +     if (!pci_bus_read_dev_vendor_id(ctrl->pcie->port->subordinate,
> > +                                     PCI_DEVFN(0, 0), &reg, 0))
> > +             return true;
> > +
> > +     if (reg != (pdev->vendor | (pdev->device << 16)))
> > +             return true;
> > +
> > +     return false;
> > +}
> > +
> >  /**
> >   * pciehp_check_presence() - synthesize event if presence has changed
> >   * @ctrl: controller to check
> > @@ -172,7 +191,8 @@ static void pciehp_check_presence(struct
> > controller *ctrl)
> >
> >       occupied = pciehp_card_present_or_link_active(ctrl);
> >       if ((occupied > 0 && (ctrl->state == OFF_STATE ||
> > -                       ctrl->state == BLINKINGON_STATE)) ||
> > +                           ctrl->state == BLINKINGON_STATE ||
> > +                           pciehp_device_replaced(ctrl))) ||
> >           (!occupied && (ctrl->state == ON_STATE ||
> >                          ctrl->state == BLINKINGOFF_STATE)))
> >               pciehp_request(ctrl, PCI_EXP_SLTSTA_PDC);