Re: [PULL 027/115] hw/i386/vmport: Propagate IOPort read to vCPU EAX register

[Laurent Vivier]

On 11/06/2020 21:43, Paolo Bonzini wrote:
> From: Liran Alon <liran.alon@oracle.com>
> 
> vmport_ioport_read() returns the value that should propagate to vCPU EAX
> register when guest reads VMPort IOPort (i.e. By x86 IN instruction).
> 
> However, because vmport_ioport_read() calls cpu_synchronize_state(), the
> returned value gets overridden by the value in QEMU vCPU EAX register.
> i.e. cpu->env.regs[R_EAX].
> 
> To fix this issue, change vmport_ioport_read() to explicitly override
> cpu->env.regs[R_EAX] with the value it wish to propagate to vCPU EAX
> register.
> 
> Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com>
> Signed-off-by: Liran Alon <liran.alon@oracle.com>
> Message-Id: <20200312165431.82118-4-liran.alon@oracle.com>
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> ---
>  hw/core/machine.c |  1 +
>  hw/i386/vmport.c  | 32 +++++++++++++++++++++++++++++---
>  2 files changed, 30 insertions(+), 3 deletions(-)
> 
> diff --git a/hw/core/machine.c b/hw/core/machine.c
> index bb3a7b18b1..83f0fe5c91 100644
> --- a/hw/core/machine.c
> +++ b/hw/core/machine.c
> @@ -43,6 +43,7 @@ GlobalProperty hw_compat_4_2[] = {
>      { "qxl", "revision", "4" },
>      { "qxl-vga", "revision", "4" },
>      { "fw_cfg", "acpi-mr-restore", "false" },
> +    { "vmport", "x-read-set-eax", "off" },

This is modifying the hw_compat_4_2 properties while qemu-5.0 has been
already released. I think all the vmport property updates [1] should go
to hw_compat_5_0.

Liran? Paolo?

Thanks,
Laurent

[1]

b889212973da hw/i386/vmport: Propagate IOPort read to vCPU EAX register
0342ee761ef2 hw/i386/vmport: Set EAX to -1 on failed and unsupported
commands
f8bdc550370f hw/i386/vmport: Report vmware-vmx-type in CMD_GETVERSION
aaacf1c15a22 hw/i386/vmport: Add support for CMD_GETBIOSUUID

    { "vmport", "x-read-set-eax", "off" },
    { "vmport", "x-signal-unsupported-cmd", "off" },
    { "vmport", "x-report-vmx-type", "off" },
    { "vmport", "x-cmds-v2", "off" },