Hi,
On 16/05/2017 02:17, David Daney wrote:
> When checking to see if a PCI bus can safely be reset, we check to see
> if any of the children have their PCI_DEV_FLAGS_NO_BUS_RESET flag set.
> As these devices are know not to behave well after a bus reset.
nit: s/know/known
>
> Some PCIe root port bridges also do not behave well after a bus reset,
> sometimes causing the devices behind the bridge to become unusable.
>
> Add a check for the PCI_DEV_FLAGS_NO_BUS_RESET flag being set in the
> bridge device to allow these bridges to be flagged, and prevent their
> buses from being reset.
>
> A follow on patch will add a quirk for this type of bridge.
>
> Signed-off-by: David Daney <david.daney@xxxxxxxxxx>
Thanks
Eric
> ---
> drivers/pci/pci.c | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
> index b01bd5b..b64e4d1 100644
> --- a/drivers/pci/pci.c
> +++ b/drivers/pci/pci.c
> @@ -4318,6 +4318,10 @@ static bool pci_bus_resetable(struct pci_bus *bus)
> {
> struct pci_dev *dev;
>
> +
> + if (bus->self && (bus->self->dev_flags & PCI_DEV_FLAGS_NO_BUS_RESET))
> + return false;
> +
> list_for_each_entry(dev, &bus->devices, bus_list) {
> if (dev->dev_flags & PCI_DEV_FLAGS_NO_BUS_RESET ||
> (dev->subordinate && !pci_bus_resetable(dev->subordinate)))
>
