[RFC PATCH 3/3] docs/about/deprecated: Deprecate the qemu-system-i386 binary

Thomas Huth posted 3 patches 2 years, 9 months ago
Maintainers: Eduardo Habkost <eduardo@habkost.net>, Marcel Apfelbaum <marcel.apfelbaum@gmail.com>, "Philippe Mathieu-Daudé" <philmd@linaro.org>, Yanan Wang <wangyanan55@huawei.com>, Paolo Bonzini <pbonzini@redhat.com>
[RFC PATCH 3/3] docs/about/deprecated: Deprecate the qemu-system-i386 binary
Posted by Thomas Huth 2 years, 9 months ago
Aside from not supporting KVM on 32-bit hosts, the qemu-system-x86_64
binary is a proper superset of the qemu-system-i386 binary. And with
the 32-bit x86 host support being deprecated now, it is possible to
deprecate the qemu-system-i386 binary now, too.

With regards to 32-bit KVM support in the x86 Linux kernel,
the developers confirmed that they do not need a recent
qemu-system-i386 binary here:

 https://lore.kernel.org/kvm/Y%2ffkTs5ajFy0hP1U@google.com/

Signed-off-by: Thomas Huth <thuth@redhat.com>
---
 docs/about/deprecated.rst | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/docs/about/deprecated.rst b/docs/about/deprecated.rst
index 1ca9dc33d6..c205816c7d 100644
--- a/docs/about/deprecated.rst
+++ b/docs/about/deprecated.rst
@@ -34,6 +34,22 @@ deprecating the build option and no longer defend it in CI. The
 ``--enable-gcov`` build option remains for analysis test case
 coverage.
 
+``qemu-system-i386`` binary (since 8.1)
+'''''''''''''''''''''''''''''''''''''''
+
+The ``qemu-system-i386`` binary was mainly useful for running with KVM
+on 32-bit x86 hosts, but most Linux distributions already removed their
+support for 32-bit x86 kernels, so hardly anybody still needs this. The
+``qemu-system-x86_64`` binary is a proper superset and can be used to
+run 32-bit guests by selecting a 32-bit CPU model, including KVM support
+on x86_64 hosts. Thus users are recommended to reconfigure their systems
+to use the ``qemu-system-x86_64`` binary instead. If a 32-bit CPU guest
+environment should be enforced, you can switch off the "long mode" CPU
+flag with ``-cpu max,lm=off``, or rename/symlink ``qemu-system-x86_64``
+to ``qemu-system-i386`` -- QEMU will then run with the 64-bit extensions
+disabled.
+
+
 System emulator command line arguments
 --------------------------------------
 
-- 
2.31.1
Re: [RFC PATCH 3/3] docs/about/deprecated: Deprecate the qemu-system-i386 binary
Posted by Philippe Mathieu-Daudé 2 years, 4 months ago
On 25/4/23 15:38, Thomas Huth wrote:
> Aside from not supporting KVM on 32-bit hosts, the qemu-system-x86_64
> binary is a proper superset of the qemu-system-i386 binary. And with
> the 32-bit x86 host support being deprecated now, it is possible to
> deprecate the qemu-system-i386 binary now, too.
> 
> With regards to 32-bit KVM support in the x86 Linux kernel,
> the developers confirmed that they do not need a recent
> qemu-system-i386 binary here:
> 
>   https://lore.kernel.org/kvm/Y%2ffkTs5ajFy0hP1U@google.com/
> 
> Signed-off-by: Thomas Huth <thuth@redhat.com>

Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Wilfred Mallawa <wilfred.mallawa@wdc.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>

> ---
>   docs/about/deprecated.rst | 16 ++++++++++++++++
>   1 file changed, 16 insertions(+)
> 
> diff --git a/docs/about/deprecated.rst b/docs/about/deprecated.rst
> index 1ca9dc33d6..c205816c7d 100644
> --- a/docs/about/deprecated.rst
> +++ b/docs/about/deprecated.rst
> @@ -34,6 +34,22 @@ deprecating the build option and no longer defend it in CI. The
>   ``--enable-gcov`` build option remains for analysis test case
>   coverage.
>   
> +``qemu-system-i386`` binary (since 8.1)
> +'''''''''''''''''''''''''''''''''''''''
> +
> +The ``qemu-system-i386`` binary was mainly useful for running with KVM
> +on 32-bit x86 hosts, but most Linux distributions already removed their
> +support for 32-bit x86 kernels, so hardly anybody still needs this. The
> +``qemu-system-x86_64`` binary is a proper superset and can be used to
> +run 32-bit guests by selecting a 32-bit CPU model, including KVM support
> +on x86_64 hosts. Thus users are recommended to reconfigure their systems
> +to use the ``qemu-system-x86_64`` binary instead. If a 32-bit CPU guest
> +environment should be enforced, you can switch off the "long mode" CPU
> +flag with ``-cpu max,lm=off``, or rename/symlink ``qemu-system-x86_64``
> +to ``qemu-system-i386`` -- QEMU will then run with the 64-bit extensions
> +disabled.
> +
> +
>   System emulator command line arguments
>   --------------------------------------
>