On 04/04/2023 17.42, BALATON Zoltan wrote:
On Tue, 4 Apr 2023, Cédric Le Goater wrote:
[ adding Zoltan ]
On 4/4/23 16:00, Thomas Huth wrote:
On 05/02/2023 23.12, Mark Cave-Ayland wrote:
On 30/01/2023 20:45, Alex Bennée wrote:
Daniel P. Berrangé <berrange@xxxxxxxxxx> writes:
On Mon, Jan 30, 2023 at 11:47:02AM +0000, Peter Maydell wrote:
On Mon, 30 Jan 2023 at 11:44, Thomas Huth <thuth@xxxxxxxxxx> wrote:
Testing 32-bit host OS support takes a lot of precious time during
the QEMU
contiguous integration tests, and considering that many OS vendors
stopped
shipping 32-bit variants of their OS distributions and most hardware
from
the past >10 years is capable of 64-bit
True for x86, not necessarily true for other architectures.
Are you proposing to deprecate x86 32-bit, or all 32-bit?
I'm not entirely sure about whether we're yet at a point where
I'd want to deprecate-and-drop 32-bit arm host support.
Do we have a feeling on which aspects of 32-bit cause us the support
burden ? The boring stuff like compiler errors from mismatched integer
sizes is mostly quick & easy to detect simply through a cross compile.
I vaguely recall someone mentioned problems with atomic ops in the past,
or was it 128-bit ints, caused implications for the codebase ?
Atomic operations on > TARGET_BIT_SIZE and cputlb when
TCG_OVERSIZED_GUEST is set. Also the core TCG code and a bunch of the
backends have TARGET_LONG_BITS > TCG_TARGET_REG_BITS ifdefs peppered
throughout.
I am one of an admittedly small group of people still interested in
using KVM-PR on ppc32 to boot MacOS, although there is some interest on
using 64-bit KVM-PR to run super-fast MacOS on modern Talos hardware.
From my perspective losing the ability to run 64-bit guests on 32-bit
hardware with TCG wouldn't be an issue, as long as it were still
possible to use qemu-system-ppc on 32-bit hardware using both TCG and
KVM to help debug the remaining issues.
Hi Mark!
Just out of curiosity (since we briefly talked about 32-bit KVM on ppc in
today's QEMU/KVM call - in the context of whether qemu-system-ppc64 is a
proper superset of qemu-system-ppc when it comes to building a unified
qemu-system binary): What host machine are you using for running KVM-PR?
And which QEMU machine are you using for running macOS? The mac99 or the
g3beige machine?
Zoltan, what about the pegasos2 and sam460ex machines ? can they be run
under KVM ?
I don't know as I don't have PPC hardware to test on but theoretically they
should work. Although BookE KVM was dropped from Linux I think so sam460ex
could only work with an old kernel on a BookE host which is now rare
[...]
Thanks for your explanations, that indeed helps to understand the situation!
But are you sure about the BookE KVM removal in the Linux kernel? ... when I
look at the arch/powerpc/kvm/ folder there, I can still see some files there
with "booke" in the name?
Thomas
