On Fri, Nov 21, 2014 at 11:24:02AM -0700, Alex Williamson wrote: > This is really 2 sets of 2 patches, but they both add bits to > dev_flags so are included together. > > This fixes two problems we've seen with resets. The first is for > devices that advertise a PM reset mechanism, but it doesn't appear to > do anything. We add a quirk and flags bit to indicate the PM reset > mechanism isn't viable. This happens on some AMD GPUs and causes > vfio-pci to assume the PM reset was successful when it really did > nothing and we should have escalated to a PCI bus reset. Alex > Deucher confirms that PM reset isn't used by graphics drivers. The > exclusion here is for users of pci_reset_function(), which mostly > only includes pci-sysfs and drivers like legacy KVM device assignment > and VFIO. > > The second issue is a problem identified with an Atheros wifi chip > where in performing a bus reset of the device, we not only permanently > lose access to the device, but it introduces host stability issues if > we try to access it. I've been unsuccessful in finding any way to > make the device behave or in finding anyone with access to hardware > documentation and errata for this device, so it seems like the most > appropriate path is to blacklist bus resets for topologies including > this device. The second two patches add infrastructure and quirks to > do this. Thanks, > > Alex > > --- > > Alex Williamson (4): > PCI: quirk Atheros AR93xx to avoid bus reset > PCI: Allow device quirks to exclude bus reset I applied these two (above) to for-linus for v3.19, thanks. > PCI: quirk AMD/ATI VGA cards to avoid PM reset > PCI: Allow device quirks to exclude D3->D0 PM reset > > > drivers/pci/pci.c | 42 +++++++++++++++++++++++++++++++++++++----- > drivers/pci/quirks.c | 35 +++++++++++++++++++++++++++++++++++ > include/linux/pci.h | 4 ++++ > 3 files changed, 76 insertions(+), 5 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
