On Mon, Nov 10, 2025 at 11:02:32PM +0000, David Matlack wrote: > On 2025-11-10 02:32 PM, Alex Mastro wrote: > > On Mon, Nov 10, 2025 at 10:03:54PM +0000, David Matlack wrote: > > > On 2025-11-10 01:10 PM, Alex Mastro wrote: > > > > + > > > > + hdr = vfio_iommu_info_cap_hdr(buf, > > > > VFIO_IOMMU_TYPE1_INFO_CAP_IOVA_RANGE); > > > > + if (!hdr) > > > > + goto free_buf; > > > > > > Is this to account for running on old versions of VFIO? Or are there > > > some scenarios when VFIO can't report the list of IOVA ranges? > > > > I wanted to avoid being overly assertive in this low-level helper function, > > mostly out of ignorance about where/in which system states this capability > > may > > not be reported. > > Makes sense, but IIUC a failure here will eventually turn into an > assertion failure in all callers that exist today. So there's currently > no reason to plumb it up the stack.
Yes, the first part is true. > > For situations like this, I think we should err on asserting at the > lower level helpers, and only propagating errors up as needed. That > keeps all the happy-path callers simple, and those should be the > majority of callers (if not all callers). SGTM -- I will do this.

