On Thu, 7 Nov 2019 21:30:41 +0000, Parav Pandit wrote: > > -----Original Message----- > > From: kvm-owner@xxxxxxxxxxxxxxx <kvm-owner@xxxxxxxxxxxxxxx> On Behalf > > Of Jakub Kicinski > > Sent: Thursday, November 7, 2019 2:43 PM > > To: Parav Pandit <parav@xxxxxxxxxxxx> > > Cc: alex.williamson@xxxxxxxxxx; davem@xxxxxxxxxxxxx; > > kvm@xxxxxxxxxxxxxxx; netdev@xxxxxxxxxxxxxxx; Saeed Mahameed > > <saeedm@xxxxxxxxxxxx>; kwankhede@xxxxxxxxxx; leon@xxxxxxxxxx; > > cohuck@xxxxxxxxxx; Jiri Pirko <jiri@xxxxxxxxxxxx>; linux- > > rdma@xxxxxxxxxxxxxxx > > Subject: Re: [PATCH net-next 16/19] net/mlx5: Implement dma ops and params > > for mediated device Please try to avoid generating those headers, you're not an occasional contributor. They're annoying and a waste of space :( > > On Thu, 7 Nov 2019 10:08:31 -0600, Parav Pandit wrote: > > > Implement dma ops wrapper to divert dma ops to its parent PCI device > > > because Intel IOMMU (and may be other IOMMU) is limited to PCI devices. > > > > > > Reviewed-by: Saeed Mahameed <saeedm@xxxxxxxxxxxx> > > > Signed-off-by: Parav Pandit <parav@xxxxxxxxxxxx> > > > > Isn't this supposed to use PASSID or whatnot? Could you explain a little? This > > mdev stuff is pretty new to networking folks.. > > Currently series doesn't support PCI PASID. > While doing dma mapping, Intel IOMMU expects dma device to be PCI device in few function traces like, find_or_alloc_domain(), > Since mdev bus is not a PCI bus, DMA mapping needs to go through its parent PCI device. > Otherwise dma ops on mdev devices fails, as I think it fails to identify how to perform the translations. > (It doesn't seem to consult its parent device). What's missing for PASSID to work? HW support? FW support? IOMMU plumbing? mdev plumbing? mlx5 plumbing?
