On Fri, Feb 12, 2021 at 11:30:41AM +0000, Steven Price wrote: > On 11/02/2021 20:21, sonicadvance1@gmail.com wrote: > > Why do we need compatibility layers? > > There are ARMv8 CPUs that only support AArch64 but still need to run > > AArch32 applications. > > Cortex-A34/R82 and other cores are prime examples of this. > > Additionally if a user is needing to run legacy 32-bit x86 software, it > > needs the same compatibility layer. > Unless I'm much mistaken QEMU's user mode already does this - admittedly I > don't tend to run "legacy 32-bit x86 software". Yes, this has been deployed on Debian for a long time - you can install any combination of Debian architectures on a single system and it will use qemu to run binaries that can't be supported natively by the hardware.