On Tue, 13 Apr 2021, Boris Ostrovsky wrote: > On 4/13/21 2:14 AM, Juergen Gross wrote: > > In x86 kernel development the question came up whether we need to > > support XENFEAT_gnttab_map_avail_bits not being set when running as a PV > > guest. > > > > This feature is active for PV guests since Xen 3.4. > > > > So the basic question is: which is the oldest version of Xen we want to > > support in the Linux kernel? As far as I know there is no Xen based > > product in productive use with Xen older than 4.2. > > > > Would we be fine to drop support for older versions (feel free to > > suggest other versions than 4.2 as the first to be supported Xen > > version)? > > > > In case the answer is yes, I'd post some patches to clean up the kernel, > > including a safety net to bail out in case a feature needed isn't > > available. > > Sounds good to me.
For ARM, the Xen ABI became stable only with Xen 4.4.
