Re: [PATCH v6 1/9] PCI/ERR: Update error status after reset_link()

[Bjorn Helgaas]

On Fri, Jul 26, 2019 at 02:43:11PM -0700, sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx wrote:
> From: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx>
> 
> Commit bdb5ac85777d ("PCI/ERR: Handle fatal error recovery") uses
> reset_link() to recover from fatal errors. But, if the reset is
> successful there is no need to continue the rest of the error recovery
> checks. Also, during fatal error recovery, if the initial value of error
> status is PCI_ERS_RESULT_DISCONNECT or PCI_ERS_RESULT_NO_AER_DRIVER then
> even after successful recovery (using reset_link()) pcie_do_recovery()
> will report the recovery result as failure. So update the status of
> error after reset_link().
> 
> Fixes: bdb5ac85777d ("PCI/ERR: Handle fatal error recovery")
> Cc: Ashok Raj <ashok.raj@xxxxxxxxx>
> Cc: Keith Busch <keith.busch@xxxxxxxxx>
> Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx>
> ---
>  drivers/pci/pcie/err.c | 11 ++++++++---
>  1 file changed, 8 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/pci/pcie/err.c b/drivers/pci/pcie/err.c
> index 773197a12568..aecec124a829 100644
> --- a/drivers/pci/pcie/err.c
> +++ b/drivers/pci/pcie/err.c
> @@ -204,9 +204,13 @@ void pcie_do_recovery(struct pci_dev *dev, enum pci_channel_state state,
>  	else
>  		pci_walk_bus(bus, report_normal_detected, &status);
>  
> -	if (state == pci_channel_io_frozen &&
> -	    reset_link(dev, service) != PCI_ERS_RESULT_RECOVERED)
> -		goto failed;
> +	if (state == pci_channel_io_frozen) {
> +		status = reset_link(dev, service);
> +		if (status != PCI_ERS_RESULT_RECOVERED)
> +			goto failed;
> +		else
> +			goto done;

This will be easier to read without the negation, i.e.,

                if (status == PCI_ERS_RESULT_RECOVERED)
                        goto done;
                else
                        goto failed;

> +	}
>  
>  	if (status == PCI_ERS_RESULT_CAN_RECOVER) {
>  		status = PCI_ERS_RESULT_RECOVERED;
> @@ -228,6 +232,7 @@ void pcie_do_recovery(struct pci_dev *dev, enum pci_channel_state state,
>  	if (status != PCI_ERS_RESULT_RECOVERED)
>  		goto failed;
>  
> +done:
>  	pci_dbg(dev, "broadcast resume message\n");
>  	pci_walk_bus(bus, report_resume, &status);
>  
> -- 
> 2.21.0
>