Thomas Huth <th...@redhat.com> writes:
> On 26/09/2019 15.46, Christian Borntraeger wrote: >> >> >> On 26.09.19 14:58, Daniel P. Berrangé wrote: >>> On Thu, Sep 26, 2019 at 08:50:36AM +0100, Peter Maydell wrote: >>>> On Thu, 26 Sep 2019 at 00:31, Alex Bennée <alex.ben...@linaro.org> wrote: >>>>> >>>>> The 32 bit hosts are already a second class citizen especially with >>>>> support for running 64 bit guests under TCG. We are also limited by >>>>> testing as actual working 32 bit machines are getting quite rare in >>>>> developers personal menageries. For TCG supporting newer types like >>>>> Int128 is a lot harder with 32 bit calling conventions compared to >>>>> their larger bit sized cousins. Fundamentally address space is the >>>>> most useful thing for the translator to have even for a 32 bit guest a >>>>> 32 bit host is quite constrained. >>>>> >>>>> As far as I'm aware 32 bit KVM users are even less numerous. Even >>>>> ILP32 doesn't make much sense given the address space QEMU needs to >>>>> manage. >>>> >>>> For KVM we should wait until the kernel chooses to drop support, >>>> I think. >>> >>> What if the kernel is waiting for QEMU to drop support too ;-P >> >> For what its worth on kvm/s390 we never cared about implementing >> 32 bit. > > Looking at tcg/s390/tcg-target.inc.c : > > ... > /* We only support generating code for 64-bit mode. */ > #if TCG_TARGET_REG_BITS != 64 > #error "unsupported code generation mode" > #endif > ... > > ... it seems to me that TCG does not support 32-bit on s390 either. I > think we can remove s390 (32-bit) from the list completely? It's the same for riscv32 I think. > > Thomas -- Alex Bennée
