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charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Proofpoint-GUID: _xi9pacj57s62QZ_ovfsVkOHDmrusefo X-Proofpoint-ORIG-GUID: _xi9pacj57s62QZ_ovfsVkOHDmrusefo X-Authority-Analysis: v=2.4 cv=N+kZ0W9B c=1 sm=1 tr=0 ts=6a2038a5 cx=c_pps a=cFYjgdjTJScbgFmBucgdfQ==:117 a=2UbFsIa4v//lIgRL4kGwwA==:17 a=IkcTkHD0fZMA:10 a=FelO9ux0wxsA:10 a=VkNPw1HP01LnGYTKEx00:22 a=7x6HtfJdh03M6CCDgxCd:22 a=jCddH8ec0KUNCymVuxII:22 a=VabnemYjAAAA:8 a=AWNa1KPf0UDjnrnzYgsA:9 a=QEXdDO2ut3YA:10 a=scEy_gLbYbu1JhEsrz4S:22 a=gKebqoRLp9LExxC7YDUY:22 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwNjAzMDEzOCBTYWx0ZWRfXzkPZ+SYbALPl L72OhZEbsjjRP4wC57GcidunS0WJmLHLQ6zk0Eo8yGIbBaptQSfKDBvW8lTmu49bN2j5MSEuEot aoRikKZGBR5S8YsnswjPhowN8kc1mT+M/3DohRkZ10/w2logT9gcruVJB+dLgS3Jp7YU2NqY0hQ mFz2SuvmSFhboxUp1J8G265Z06/sYoo3/AR6mNWWM9uPrnDaQ9tRrpFP9z3+7MPoi22PrIy11sw 9Ohe6E9enpyeXi9+Tj63GythzdbppzmG5ItyKwhkY8/tr/A99B78ev4KK0cnuueNaKAh6Ut0859 abjfJrsvlbrtC2OvPhsPcsHcAzDXZqi0+/c1JZURTipIJ0TIUsBndKjo0FKIw4iYEA7XugAiW+w GffnZq3TMIzWUJcH7iK9uj7rCOsYHqbAk8eRNdXXv4YKJUZ8Tzdi3gj9gnfbXU27IQBEgEBi296 7YkQL5tjjAUhMQcEhMA== X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1143,Hydra:6.1.125,FMLib:17.12.100.49 definitions=2026-06-03_05,2026-05-28_03,2025-10-01_01 Hi Alex, On 02/06/2026 20:14, Alex Williamson wrote: > > On Tue, 2 Jun 2026 17:50:04 +0100 > Matt Evans wrote: >> On 29/05/2026 00:14, Alex Williamson wrote: >>> On Wed, 27 May 2026 03:23:12 -0700 >>> Matt Evans wrote: >>>> + uint32_t old_attr = priv->memattr; >>>> + >>>> + if (flags & VFIO_DEVICE_FEATURE_SET) { >>>> + switch(db_attr.memattr) { >>>> + case VFIO_DEVICE_FEATURE_DMA_BUF_MEMATTR_NC: >>>> + case VFIO_DEVICE_FEATURE_DMA_BUF_MEMATTR_WC: >>>> + priv->memattr = db_attr.memattr; >>>> + break; >>>> + >>>> + default: >>>> + ret = -ENOTSUPP; >>> >>> -EINVAL >> >> I'd like to push back on this one; ENOTSUPP distinguishes trying to use >> a wild attribute value from all manner of other screwups such as >> trying to GET (with it no longer supported), passing an fd that isn't a >> DMABUF, etc. >> >> I'm not wed to the value ENOTSUPP, just something distinctive versus the >> other errors userspace might see, and that value seems appropriate. > > It needs to be a uAPI errno though, aiui ENOTSUPP is an internal NFS > errno. How about EOPNOTSUPP? Thanks, Ew, right! TIL, and it's caught by checkpatch too (which I fastidiously run but still missed this somehow...) :( "ENOTSUPP is not a standard error code and should be avoided in new patches. EOPNOTSUPP should be used instead." Fixed. Thanks, Matt