Messages in this thread | | | Subject | Re: [PATCH] iommu/amd - Use dev_err to send events to the system log | From | "Hook, Gary" <> | Date | Wed, 14 Feb 2018 09:58:31 -0500 |
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On 2/14/2018 6:49 AM, Joerg Roedel wrote: > On Tue, Feb 13, 2018 at 02:24:56PM -0500, Hook, Gary wrote: >> Without actually running a driver and getting some debug info, I'll just >> say that my example compiled, the amd_iommu structure points to a pci_dev >> which contains a device, and the two possibilities are likely equivalent. >> >> I'll vet that, of course, but working under the assumption that they are >> equivalent, the question becomes, do you have a preference? > > They are not equivalent, your version points to the pci_dev containing > the IOMMU, my version points to the (virtual) iommu-device for that > particular iommu in the kernel. > > So the difference in the prefix is: > > your version: '0000:00:00.2:' > > vs. my version: 'ivhd0:' > > The latter is the better prefix, because it points to the iommu. A > pci_dev can contain more than one iommu, so that prefix is not specific > enough. I know that there is currently no hardware implementing multiple > iommus on one pci_dev, but it is allowed according to the spec.
Excellent; specificity is good. I'll crank a new version using that device.
Thank you!
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