On Tue, Apr 16, 2024 at 5:37 PM Jiri Pirko <jiri@xxxxxxxxxxx> wrote: > > Tue, Apr 16, 2024 at 05:52:41AM CEST, jasowang@xxxxxxxxxx wrote: > >On Tue, Apr 16, 2024 at 12:25 AM Jiri Pirko <jiri@xxxxxxxxxxx> wrote: > >> > >> From: Jiri Pirko <jiri@xxxxxxxxxx> > >> > >> Currently there is no way for user to set what features the driver > >> should obey or not, it is hard wired in the code. > >> > >> In order to be able to debug the device behavior in case some feature is > >> disabled, introduce a debugfs infrastructure with couple of files > >> allowing user to see what features the device advertises and > >> to set filter for features used by driver. > >> > >> Example: > >> $cat /sys/bus/virtio/devices/virtio0/features > >> 1110010111111111111101010000110010000000100000000000000000000000 > >> $ echo "5" >/sys/kernel/debug/virtio/virtio0/filter_feature_add > >> $ cat /sys/kernel/debug/virtio/virtio0/filter_features > >> 5 > >> $ echo "virtio0" > /sys/bus/virtio/drivers/virtio_net/unbind > >> $ echo "virtio0" > /sys/bus/virtio/drivers/virtio_net/bind > >> $ cat /sys/bus/virtio/devices/virtio0/features > >> 1110000111111111111101010000110010000000100000000000000000000000 > >> > >> Note that sysfs "features" know already exists, this patch does not > >> touch it. > >> > >> Signed-off-by: Jiri Pirko <jiri@xxxxxxxxxx> > >> --- > > > >Note that this can be done already with vp_vdpa feature provisioning: > > > >commit c1ca352d371f724f7fb40f016abdb563aa85fe55 > >Author: Jason Wang <jasowang@xxxxxxxxxx> > >Date: Tue Sep 27 15:48:10 2022 +0800 > > > > vp_vdpa: support feature provisioning > > > >For example: > > > >vdpa dev add name dev1 mgmtdev pci/0000:02:00.0 device_features 0x300020000 > > Sure. My intension was to make the testing possible on any virtio > device. It did that actually, vp_vdpa bridge virtio-pci device into vDPA bus with mediation layer (like feature filtering etc). So it can only run on top of standard virtio-pci device. > Narrowing the testing for vpda would be limitting. Unless you want to use other transport like virtio-mmio. Thanks > > > > > >Thanks > > >
