Messages in this thread | | | Date | Fri, 10 Mar 2023 08:36:06 -0400 | From | Jason Gunthorpe <> | Subject | Re: [PATCH v2] vhost/vdpa: Add MSI translation tables to iommu for software-managed MSI |
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On Fri, Mar 10, 2023 at 04:53:42AM -0500, Michael S. Tsirkin wrote: > On Fri, Mar 10, 2023 at 05:45:46PM +0800, Jason Wang wrote: > > On Fri, Mar 10, 2023 at 4:41 PM Michael S. Tsirkin <mst@redhat.com> wrote: > > > > > > On Mon, Feb 20, 2023 at 10:37:18AM +0800, Jason Wang wrote: > > > > On Fri, Feb 17, 2023 at 8:43 PM Jason Gunthorpe <jgg@nvidia.com> wrote: > > > > > > > > > > On Fri, Feb 17, 2023 at 05:12:29AM -0500, Michael S. Tsirkin wrote: > > > > > > On Thu, Feb 16, 2023 at 08:14:50PM -0400, Jason Gunthorpe wrote: > > > > > > > On Tue, Feb 07, 2023 at 08:08:43PM +0800, Nanyong Sun wrote: > > > > > > > > From: Rong Wang <wangrong68@huawei.com> > > > > > > > > > > > > > > > > Once enable iommu domain for one device, the MSI > > > > > > > > translation tables have to be there for software-managed MSI. > > > > > > > > Otherwise, platform with software-managed MSI without an > > > > > > > > irq bypass function, can not get a correct memory write event > > > > > > > > from pcie, will not get irqs. > > > > > > > > The solution is to obtain the MSI phy base address from > > > > > > > > iommu reserved region, and set it to iommu MSI cookie, > > > > > > > > then translation tables will be created while request irq. > > > > > > > > > > > > > > Probably not what anyone wants to hear, but I would prefer we not add > > > > > > > more uses of this stuff. It looks like we have to get rid of > > > > > > > iommu_get_msi_cookie() :\ > > > > > > > > > > > > > > I'd like it if vdpa could move to iommufd not keep copying stuff from > > > > > > > it.. > > > > > > > > > > > > Absolutely but when is that happening? > > > > > > > > > > Don't know, I think it has to come from the VDPA maintainers, Nicolin > > > > > made some drafts but wasn't able to get it beyond that. > > > > > > > > Cindy (cced) will carry on the work. > > > > > > > > Thanks > > > > > > Hmm didn't see anything yet. Nanyong Sun maybe you can take a look? > > > > Just to clarify, Cindy will work on the iommufd conversion for > > vhost-vDPA, the changes are non-trivial and may take time. Before we > > are able to achieve that, I think we still need something like this > > patch to make vDPA work on software managed MSI platforms. > > > > Maybe Nanyong can post a new version that addresses the comment so far? > > > > Thanks > > Maybe but an ack from iommu maintainers will be needed anyway. Let's see > that version, maybe split the export to a patch by itself to make the > need for that ack clear.
A patch to export that function is alread posted:
https://lore.kernel.org/linux-iommu/BN9PR11MB52760E9705F2985EACCD5C4A8CBA9@BN9PR11MB5276.namprd11.prod.outlook.com/T/#u
But I do not want VDPA to mis-use it unless it also implements all the ownership stuff properly.
Jason
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