Re: [PATCH v2 2/3] target/i386: ignore CPL0-specific features in user mode emulation

[Richard Henderson <richard.henderson@linaro.org>]

On 6/26/23 10:33, Paolo Bonzini wrote:
> Features such as PCID are only accessible through privileged operations,
> and therefore have no impact on any user-mode operation.  Allow reporting
> them to programs running under user mode emulation, so that "-cpu" can be
> used with more named CPU models.
> 
> XSAVES would be similar, but it doesn't make sense to provide it until
> XSAVEC is implemented.
> 
> With this change, all CPUs up to Broadwell-v4 can be emulate.  Skylake-Client
> requires XSAVEC, while EPYC also requires SHA-NI, MISALIGNSSE and TOPOEXT.
> MISALIGNSSE is not hard to implement, but I am not sure it is worth using
> a precious hflags bit for it.
> 
> Fixes:https://gitlab.com/qemu-project/qemu/-/issues/1534
> Signed-off-by: Paolo Bonzini<pbonzini@redhat.com>
> ---
>   target/i386/cpu.c | 83 +++++++++++++++++++++++++++++++++++++++++++----
>   1 file changed, 76 insertions(+), 7 deletions(-)

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

r~