[Date Prev] | [Thread Prev] | [Thread Next] | [Date Next] -- [Date Index] | [Thread Index] | [List Home]
Subject: Re: [PATCH v2 0/2] transport-pci: Introduce legacy registers access using AQ
On Mon, May 15, 2023 at 06:00:02PM +0000, Parav Pandit wrote: > > From: Michael S. Tsirkin <mst@redhat.com> > > Sent: Monday, May 15, 2023 1:56 PM > > > > On Mon, May 15, 2023 at 05:51:05PM +0000, Parav Pandit wrote: > > > > > > > From: Michael S. Tsirkin <mst@redhat.com> > > > > Sent: Monday, May 15, 2023 1:45 PM > > > > > > > > On Mon, May 15, 2023 at 03:49:44PM +0000, Parav Pandit wrote: > > > > > All legacy interface via AQ. > > > > > All modern interface access via PCI or its own transport between > > > > > driver and > > > > device. > > > > > > > > I am wondering however about the hypervisor notifications. > > > > Generally these are the most problematic aspect here I feel. For > > > > example, how does it interact with VIRTIO_F_NOTIF_CONFIG_DATA? And > > > > generally, having both guest and host be allowed to access device's BAR > > seems problematic. > > > > Can we reserve a PF BAR region for these things or is that too expensive? > > > > > > VIRTIO_F_NOTIF_CONFIG_DATA is not present for the legacy. > > > > it is not but it just might be required, or it won't be there. > > > How can it be required if it not part of it? > I likely didn't follow your question/comment, can you please explain. VIRTIO_F_NOTIF_CONFIG_DATA is there presumably for a reason. > > > For modern device, guest driver will access the device own BAR directly with > > its own config_data anyway. > > > Should we reserve a region in the PF BAR for SF/SIOV device?, should device > > report which BAR/area to use for the given SF/SIOV device? > > > May be yes, those are different discussions with tradeoff to consider during > > SIOV discussions. It is not related to VFs. > > > > For SIOV it's a given. But we can do this for SRIOV: reserve a PF region per VF. > Each VF has its own BAR area for driver notifications. But it is passed through to guest presumably. -- MST
[Date Prev] | [Thread Prev] | [Thread Next] | [Date Next] -- [Date Index] | [Thread Index] | [List Home]