On Wed, Jan 13, 2021 at 05:04:30PM +0800, Yang Weijiang wrote:
> QEMU option -cpu max(max_features) means "Enables all features supported by
> the accelerator in the current host", this looks true for all the features
> except guest max physical address width, so add this patch to enable it.
>
> Signed-off-by: Yang Weijiang <weijiang.y...@intel.com>
> ---
> target/i386/cpu.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/target/i386/cpu.c b/target/i386/cpu.c
> index 35459a38bb..b5943406f7 100644
> --- a/target/i386/cpu.c
> +++ b/target/i386/cpu.c
> @@ -6673,7 +6673,7 @@ static void x86_cpu_realizefn(DeviceState *dev, Error
> **errp)
> warned = true;
> }
>
> - if (cpu->host_phys_bits) {
> + if (cpu->host_phys_bits || cpu->max_features) {
> /* The user asked for us to use the host physical bits */
> cpu->phys_bits = host_phys_bits;
> if (cpu->host_phys_bits_limit &&
> --
> 2.17.2
>
>
Hi,
This patch as commit 5a140b255d ("x86/cpu: Use max host physical address
if -cpu max option is applied") prevents me from using '-cpu host' while
booting an i386_defconfig kernel.
$ qemu-system-i386 \
-append console=ttyS0 \
-cpu host \
-display none \
-enable-kvm \
-initrd rootfs.cpio \
-kernel bzImage \
-serial mon:stdio
qemu-system-i386: phys-bits should be between 32 and 36 (but is 48)
Am I expected to pass "-cpu host,host-phys-bits=false" now or did this
do something unexpected?
Cheers,
Nathan
