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> > > > + if (ret) > > > > + return ret; > > > > > > Were do you allocate the second level entry for ssid 0 if we're using > > > 2-level cd tables? > > > > I don't think we need to. The entire design here has a non-valid CD entry > > for SSID 0. > > Hmm, whether we allocate a 2-level cd table would actually depend on > the "1 << cd_table->s1cdmax" v.s. CTXDESC_L2_ENTRIES, right? > > If the device supports PASID and s1cdmax is large, we should prepare > a 2-level cd tables, even if only SSID0 is used at this moment since > we have to support !0 pasids via potential SVA domains. > > In all Other cases, we would prepare a linear one. Yes, this is what arm_smmu_alloc_cd_tables() is doing. I think will was questioning if this needs to be arm_smmu_alloc_cd_ptr(master, 0); To ensure there is some memory under the SSID=0 case, but it seems we don't need that. Jason