On Tue, Feb 27, 2024 at 01:14:18PM +0000, Edmund Raile wrote: > Using LSI / Agere FW643 with vfio-pci will exhaust all > pci_reset_fn_methods, the bus reset at the end causes a broken link > only recoverable by removing power > (power-off / suspend + rescan). > Prevent this bus reset. > With this change, the device can be assigned to VMs with VFIO. > Note that it will not be reset, resulting in leaking state between VMs > and host. > > Signed-off-by: Edmund Raile <edmund.raile@xxxxxxxxx> Applied to pci/virtualization for v6.9, thank you! > --- > > I sincerely thank you for your patience and explaining > the background of pci resets which I lacked. > The commit message and comment now describe it correctly. > The comment on leaking states was added. > > Usefulness: > > The LSI FW643 PCIe->FireWire 800 interface may be EOL but it is > the only one that does not use a PCIe->PCI bridge. > It is reliable and enables FireWire audio interfaces to be used > on modern machines. > > Virtualization allows for flexible access to professional audio > software. > > It has been used in at least the following Apple machines: > MacBookPro10,1 > MacBookPro9,2 > MacBookPro6,2 > MacBookPro5,1 > Macmini6,1 > Macmini3,1 > iMac12,2 > iMac9,1 > iMac8,1 > > Implementation: > > PCI_VENDOR_ID_ATT was reused as they are identical. > > drivers/pci/quirks.c | 13 +++++++++++++ > 1 file changed, 13 insertions(+) > > diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c > index d797df6e5f3e..e0e4ad9e6d50 100644 > --- a/drivers/pci/quirks.c > +++ b/drivers/pci/quirks.c > @@ -3765,6 +3765,19 @@ DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_ATHEROS, 0x003e, quirk_no_bus_reset); > */ > DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_CAVIUM, 0xa100, quirk_no_bus_reset); > > +/* > + * Using LSI / Agere FW643 with vfio-pci will exhaust all > + * pci_reset_fn_methods, the bus reset at the end causes a broken link > + * only recoverable by removing power > + * (power-off / suspend + rescan). > + * Prevent this bus reset. > + * With this change, the device can be assigned to VMs with VFIO. > + * Note that it will not be reset, resulting in leaking state between VMs > + * and host. > + */ > +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_ATT, 0x5900, quirk_no_bus_reset); > +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_ATT, 0x5901, quirk_no_bus_reset); > + > /* > * Some TI KeyStone C667X devices do not support bus/hot reset. The PCIESS > * automatically disables LTSSM when Secondary Bus Reset is received and > -- > 2.43.0 > >
