On Fri, Mar 12, 2021 at 10:57:18PM +0000, James Puthukattukaran wrote:
> But the clearing of fatal error in the dpc_process_error is only for DPC trigger due to "unmaskable uncorrectable".
> If the trigger reason is ERR_FATAL, then it does not hit the else clause and neither is it cleared in the pci_do_recovery code.
If the reason is ERR_FATAL, then the port didn't detect the error; it is
just the first DPC capable downstream port to receive the message from
some device downstream, so there's nothing to clear in its AER register.
> From dpc_process_error with more context --
>
> else if (reason == 0 && <<<<<<< only for "unmaskable uncorrectable". What about for ERR_FATAL?
> dpc_get_aer_uncorrect_severity(pdev, &info) &&
> aer_get_device_error_info(pdev, &info)) {
> aer_print_error(pdev, &info);
> pci_aer_clear_nonfatal_status(pdev);
> pci_aer_clear_fatal_status(pdev);
> }
>
>
> > -----Original Message-----
> > From: Kelley, Sean V <sean.v.kelley@xxxxxxxxx>
> > Sent: Friday, March 12, 2021 5:25 PM
> > To: James Puthukattukaran <james.puthukattukaran@xxxxxxxxxx>;
> > Kuppuswamy, Sathyanarayanan
> > <sathyanarayanan.kuppuswamy@xxxxxxxxx>
> > Cc: Linux PCI <linux-pci@xxxxxxxxxxxxxxx>; bhelgaas@xxxxxxxxxx
> > Subject: [External] : Re: pci_do_recovery not handling fata errors
> >
> >
> >
> > > On Mar 12, 2021, at 12:56 PM, James Puthukattukaran
> > <james.puthukattukaran@xxxxxxxxxx> wrote:
> > >
> > > Hi -
> > > I’m trying to understand why pci_do_recovery() only clears non-fatal but
> > not fata errors? My immediate concern is call from dpc_handler. If a device
> > sends an ERR_FATAL to the root port, I would think that as part of recovery
> > the fatal status in the AER registers of the endpoint device would be cleared?
> > >
> >
> >
> > Adding Sathya who mentioned to me that:
> >
> > Fatal error are cleared in
> >
> > void dpc_process_error(struct pci_dev *pdev)
> >
> > 253 dpc_get_aer_uncorrect_severity(pdev, &info) &&
> > 254 aer_get_device_error_info(pdev, &info)) {
> > 255 aer_print_error(pdev, &info);
> > 256 pci_aer_clear_nonfatal_status(pdev);
> > 257 pci_aer_clear_fatal_status(pdev);
> >
> > Thanks,
> >
> > Sean
> >
> > > Snippet of concern in pci_do_recovery –
> > >
> > > /*
> > > * If we have native control of AER, clear error status in the Root
> > > * Port or Downstream Port that signaled the error. If the
> > > * platform retained control of AER, it is responsible for clearing
> > > * this status. In that case, the signaling device may not even be
> > > * visible to the OS.
> > > */
> > > if (host->native_aer || pcie_ports_native) {
> > > pcie_clear_device_status(bridge);
> > > pci_aer_clear_nonfatal_status(bridge); <<<< Just clearing
> > nonfatal. What about fatal?
> > > }
> > >
> > > Thanks
> > > James
>
