> as I remember IBM mainframes have had support for Aix/Linux guests for a while now
IBM VM has supported Linux guests ever since Linux was first ported to IBM mainframes, circa 1999-2000. Indeed, it is quite likely the initial port was done using VM.
IBM offered two versions of AIX on mainframes, AIX/370 in 1998 and AIX/ESA in 1991. However, how much code did these have in common with AIX on RS/6000? In the later case, very little – AIX/ESA is actually a port of the Mach kernel based OSF/1 to IBM mainframes, with little or no code shared with RS/6000 AIX (which contemporary AIX descends from). It actually had more in common with Digital/Compaq/HP's discontinued Tru64 UNIX (which is another OSF/1 derivative) than with AIX on RT-PC / POWER. I get the impression that AIX/370 had little or no code in common with RS/6000 AIX either – it was developed by Locus Computer Corporation – but I don't know enough about it to be sure about that. Neither AIX/370 or AIX/ESA ever saw any great adoption – both were discontinued in the 1990s, they were replaced by MVS OpenEdition (later OS/390 OpenEdition, and now z/OS Unix System Services) and also later on also by Linux.
IBM VM has supported Linux guests ever since Linux was first ported to IBM mainframes, circa 1999-2000. Indeed, it is quite likely the initial port was done using VM.
IBM offered two versions of AIX on mainframes, AIX/370 in 1998 and AIX/ESA in 1991. However, how much code did these have in common with AIX on RS/6000? In the later case, very little – AIX/ESA is actually a port of the Mach kernel based OSF/1 to IBM mainframes, with little or no code shared with RS/6000 AIX (which contemporary AIX descends from). It actually had more in common with Digital/Compaq/HP's discontinued Tru64 UNIX (which is another OSF/1 derivative) than with AIX on RT-PC / POWER. I get the impression that AIX/370 had little or no code in common with RS/6000 AIX either – it was developed by Locus Computer Corporation – but I don't know enough about it to be sure about that. Neither AIX/370 or AIX/ESA ever saw any great adoption – both were discontinued in the 1990s, they were replaced by MVS OpenEdition (later OS/390 OpenEdition, and now z/OS Unix System Services) and also later on also by Linux.