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See http://www.infradead.org/rpr.html Cc: "Tian, Kevin" , Raj Ashok , Jean-Philippe Brucker , LKML , iommu@lists.linux-foundation.org, Alex Williamson , David Woodhouse X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" On Wed, Mar 25, 2020 at 04:17:05PM -0700, Jacob Pan wrote: > Having a single UAPI version to govern the user-kernel data structures > makes compatibility check straightforward. On the contrary, supporting > combinations of multiple versions of the data can be a nightmare to > maintain. > > This patch defines a unified UAPI version to be used for compatibility > checks between user and kernel. This is bullshit. Version numbers don't scale and we've avoided them everywhere. You need need flags specifying specific behavior. > +#define IOMMU_UAPI_VERSION 1 > +static inline int iommu_get_uapi_version(void) > +{ > + return IOMMU_UAPI_VERSION; > +} Also inline functions like this in UAPI headers that actually get included by userspace programs simply don't work. _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu