Hi, On Wed, Nov 08, 2017 at 09:44:48AM -0600, Govinda Tatti wrote: > Thanks Jan for your review comments. Please see below for my comments. > > On 11/7/2017 8:40 AM, Jan Beulich wrote: > >>>>On 06.11.17 at 18:48, <govinda.ta...@oracle.com> wrote: > >>--- a/Documentation/ABI/testing/sysfs-driver-pciback > >>+++ b/Documentation/ABI/testing/sysfs-driver-pciback > >>@@ -11,3 +11,15 @@ Description: > >> #echo 00:19.0-E0:2:FF > > >> /sys/bus/pci/drivers/pciback/quirks > >> will allow the guest to read and write to the > >> configuration > >> register 0x0E. > >>+ > >>+What: /sys/bus/pci/drivers/pciback/do_flr > >>+Date: Nov 2017 > >>+KernelVersion: 4.15 > >>+Contact: xen-de...@lists.xenproject.org > >>+Description: > >>+ An option to perform a slot or bus reset when a PCI device > >>+ is owned by Xen PCI backend. Writing a string of DDDD:BB:DD.F > >>+ will cause the pciback driver to perform a slot or bus reset > >>+ if the device supports it. It also checks to make sure that > >>+ all of the devices under the bridge are owned by Xen PCI > >>+ backend. > >Why do you name this "do_flr" when you don't even try FLR, but > >go to slot or then bus reset right away. > Yes, I agree but xen toolstack has already been modified to consume"do_flr" > attribute. Hence, we are using the > function that matches with sysfs attribute. >
Hmm.. I remember some discussion from ages ago related to this. Back then it was suggested to "emulate" the flr capability (by doing slot or bus reset) for devices which don't have *native* flr available? So is this patch perhaps related to that? If the PCI device in question has native flr capability, then native flr is used, right ? I guess I should read the full patch.. -- Pasi
