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Wouldn’t range_contains() also match a subrange? Is it okay to treat a contained but non-identical decoder range as a duplicate as well? >> + return 0; >> + >> + range = kzalloc_obj(*range); >> + if (!range) >> + return -ENOMEM; >> + >> + range->pdev = pdev; >> + range->hpa_range = *hpa_range; >> + list_add_tail(&range->list, &ctx->ranges); >> + >> + return 0; >> +} >> + >> +static int cxl_hdm_ranges_collect(struct cxl_hdm_range_context *ctx, >> + struct pci_dev *pdev) >> +{ >> + struct cxl_hdm_info *info; >> + int rc; >> + >> + guard(rwsem_read)(&cxl_rwsem.dpa); >> + info = pdev->hdm; >> + if (!info) { >> + pci_err(pdev, "CXL HDM decoder state unavailable\n"); >> + return -ENXIO; >> + } >> + >> + for (int i = 0; i < info->decoder_count; i++) { >> + struct cxl_decoder_settings *settings = &info->settings[i]; >> + >> + if (!(settings->flags & CXL_DECODER_F_ENABLE)) >> + continue; >> + >> + if (settings->flags & CXL_DECODER_F_NORMALIZED_ADDRESSING) { >> + pci_err(pdev, >> + "CXL reset does not support normalized address decoders\n"); >> + return -EOPNOTSUPP; >> + } >> + >> + rc = cxl_hdm_range_add(ctx, pdev, &settings->hpa_range); >> + if (rc) >> + return rc; >> + } >> + >> + return 0; >> +} >> + >> +static int cxl_hdm_range_len(struct pci_dev *pdev, >> + const struct range *hpa_range, u64 *len) >> +{ >> + if (hpa_range->end < hpa_range->start) >> + return -EINVAL; >> + >> + if (hpa_range->start > RESOURCE_SIZE_MAX || >> + hpa_range->end > RESOURCE_SIZE_MAX) { > Given that above you established that (end >= start) couple lines above, you really only need to test end here. > >> + pci_err(pdev, >> + "CXL reset range [%#llx-%#llx] exceeds resource address size\n", >> + hpa_range->start, hpa_range->end); >> + return -EOVERFLOW; >> + } >> + >> + *len = range_len(hpa_range); >> + if (!*len || *len > RESOURCE_SIZE_MAX) { >> + pci_err(pdev, >> + "CXL reset range [%#llx-%#llx] exceeds resource size\n", >> + hpa_range->start, hpa_range->end); >> + return -EOVERFLOW; >> + } >> + >> + if (*len > SIZE_MAX) { >> + pci_err(pdev, >> + "CXL reset range [%#llx-%#llx] exceeds cache flush size\n", >> + hpa_range->start, hpa_range->end); >> + return -EOVERFLOW; >> + } >> + >> + return 0; >> +} > This function is doing too much. I suggest you rename it cxl_hdm_range_validate() and drop the *len parameter. And just assign len from range_len(hpa_range) once it's validated. I'll paste a diff at the end as a suggestion. I applied this refactor in v11: the helper is now cxl_hdm_range_validate(), it no longer has a len output parameter, and the caller assigns range_len() after validation. > >> + >> +static int cxl_hdm_range_request(struct cxl_hdm_range *range) >> +{ >> + struct pci_dev *pdev = rang -- Regards, Srirangan