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    SubjectRe: [PATCH 1/2] PCI: Allow PCI_DEV_FLAGS_NO_BUS_RESET to be used on bus device.
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    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@cavium.com>

    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)))
    >

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