On Wed, Jul 14, 2021 at 10:29 AM Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> wrote:
>
> On Wed, Jul 14, 2021 at 10:03:09AM -0400, David Jeffery wrote:
> >
> > diff --git a/drivers/usb/host/ehci-hcd.c b/drivers/usb/host/ehci-hcd.c
> > index 36f5bf6a0752..2283205d4b40 100644
> > --- a/drivers/usb/host/ehci-hcd.c
> > +++ b/drivers/usb/host/ehci-hcd.c
> > @@ -704,14 +704,18 @@ static irqreturn_t ehci_irq (struct usb_hcd *hcd)
> > {
> > struct ehci_hcd *ehci = hcd_to_ehci (hcd);
> > u32 status, masked_status, pcd_status = 0, cmd;
> > + u32 current_status;
> > int bh;
> >
> > spin_lock(&ehci->lock);
> >
> > - status = ehci_readl(ehci, &ehci->regs->status);
> > + status = 0;
> >
> > + current_status = ehci_readl(ehci, &ehci->regs->status);
> > +restart:
> > + status |= current_status;
> > /* e.g. cardbus physical eject */
> > - if (status == ~(u32) 0) {
> > + if (current_status == ~(u32) 0) {
> > ehci_dbg (ehci, "device removed\n");
> > goto dead;
> > }
>
> Mild stylistic quibble: I generally prefer to have a blank line before a
> /* ... */ comment. And it doesn't seem reasonable to have a blank line
> between "status = 0" and the current_status assignment, since those are
> similar once-only things before the beginning of the "restart" loop.
> Also, I would move the "status |= current_status" line after the test
> for device removed, since that test doesn't use status.
>
> But obviously none of these things affect the patch's correntness.
I'll update it with requested changes and resend it.
>
> You can choose to submit a new version of the patch with those stylistic
> changes, or if you prefer, just stick with this version. Either way,
>
> Acked-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
>
> Does this issue affect any other PCI-based host controller drivers?
>
> Alan Stern
>
Possibly. The uhci driver should have the same issue if hardware
exists with it and has MSI for it. I suspect the ohci driver has a
similar issue, but I'm not familiar enough with its interfaces and
specification to say for sure.
David Jeffery
