On Mon, Mar 08, 2021 at 02:21:30PM +0000, Antti Järvinen wrote: > Some TI KeyStone C667X devices do no support bus/hot reset. Its PCIESS > automatically disables LTSSM when secondary bus reset is received and > device stops working. Prevent bus reset by adding quirk_no_bus_reset to > the device. With this change device can be assigned to VMs with VFIO, > but it will leak state between VMs. s/do no/do/not/ (also in the comment below) Does the user get any indication of this leaking state? I looked through drivers/vfio and drivers/pci, but I haven't found anything yet. We *could* log something in quirk_no_bus_reset(), but that would just be noise for people who don't pass the device through to a VM. So maybe it would be nicer if we logged something when we actually *do* pass it through to a VM. > Reference: https://e2e.ti.com/support/processors/f/791/t/954382 > Signed-off-by: Antti Järvinen <antti.jarvinen@xxxxxxxxx> > --- > drivers/pci/quirks.c | 10 ++++++++++ > 1 file changed, 10 insertions(+) > > diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c > index 653660e3ba9e..d9201ad1ca39 100644 > --- a/drivers/pci/quirks.c > +++ b/drivers/pci/quirks.c > @@ -3578,6 +3578,16 @@ DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_ATHEROS, 0x0034, quirk_no_bus_reset); > */ > DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_CAVIUM, 0xa100, quirk_no_bus_reset); > > +/* > + * Some TI keystone C667X devices do no support bus/hot reset. > + * Its PCIESS automatically disables LTSSM when secondary bus reset is > + * received and device stops working. Prevent bus reset by adding > + * quirk_no_bus_reset to the device. With this change device can be > + * assigned to VMs with VFIO, but it will leak state between VMs. > + * Reference https://e2e.ti.com/support/processors/f/791/t/954382 > + */ > +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_TI, 0xb005, quirk_no_bus_reset); > + > static void quirk_no_pm_reset(struct pci_dev *dev) > { > /* > -- > 2.17.1 >
