Re: [PATCH] pciehp: Acknowledge the spurious "cmd completed" event.

[Bjorn Helgaas <bhelgaas@google.com>]

On Mon, Nov 25, 2013 at 07:03:11PM +0000, Rajat Jain wrote:
> Hello,
> 
> > > On a different note, I feel there is still a need to apply my original
> > patch. There is still an open problem in case of spurious interrupts (or
> > in any case where the condition "if (slot_status & PCI_EXP_SLTSTA_CC)"
> > becomes true in pcie_write_cmd()). That is because once that happens, we
> > never clear that interrupt, and no further hotplug interrupts shall be
> > received unless we do that.
> > 
> > I agree this is an issue and we should address it somehow.  My
> > hesitation is just that I'd prefer to do some more aggressive
> > restructuring rather than apply a point fix.  For example:
> 
> OK, I'll attempt to fix it that way when I get time.
> 
> > 
> > - We currently look at PCI_EXP_SLTSTA_CC in pcie_isr(), pcie_poll_cmd(),
> > and pcie_write_cmd().  I think it would be better to look at it only in
> > pcie_isr().
> > 
> > - I don't think pcie_poll_cmd() should exist at all; we should poll by
> > calling pcie_isr() instead.
> > 
> > - We need pcie_write_cmd(), but I think the way it waits is backwards.
> >  Currently we issue the command, then wait for it to complete.  I think
> > we should issue the command, note the current time, and return without
> > waiting.  The *next* time we need to issue a command, we can wait for
> > completion of the previous one (or timeout) if necessary.
> > 
> > But maybe we need the point fix in the interim, especially if anybody
> > can actually produce the scenario you mention.
> 
> Ok.

This patch is still in patchwork, but I've lost track of where we are.
Did you resolve this in the series that I just applied, or is it still
an outstanding issue?

Bjorn