On Tuesday, April 8th, 2025 at 9:07 AM, Alejandro Vallejo <agarc...@amd.com>
wrote:
>
>
> From: "Daniel P. Smith" dpsm...@apertussolutions.com
>
>
> Enable selecting the mode in which the domain will be built and ran. This
> includes:
>
> - whether it will be either a 32/64 bit domain
> - if it will be run as a PV or HVM domain
> - and if it will require a device model (not applicable for dom0)
>
> In the device tree, this will be represented as a bit map that will be carried
> through into struct boot_domain.
>
> Signed-off-by: Daniel P. Smith dpsm...@apertussolutions.com
>
> Reviewed-by: Jason Andryuk jason.andr...@amd.com
>
> ---
> xen/arch/x86/domain-builder/fdt.c | 19 +++++++++++++++++++
> xen/arch/x86/include/asm/boot-domain.h | 5 +++++
> xen/arch/x86/setup.c | 3 ++-
> 3 files changed, 26 insertions(+), 1 deletion(-)
>
> diff --git a/xen/arch/x86/domain-builder/fdt.c
> b/xen/arch/x86/domain-builder/fdt.c
> index 4c6aafe195..da65f6a5a0 100644
> --- a/xen/arch/x86/domain-builder/fdt.c
> +++ b/xen/arch/x86/domain-builder/fdt.c
> @@ -193,6 +193,25 @@ static int __init process_domain_node(
> bd->domid = (domid_t)val;
>
> printk(" domid: %d\n", bd->domid);
>
> }
> + else if ( strncmp(prop_name, "mode", name_len) == 0 )
> + {
> + if ( fdt_prop_as_u32(prop, &bd->mode) != 0 )
>
> + {
> + printk(" failed processing mode for domain %s\n", name);
> + return -EINVAL;
> + }
> +
> + printk(" mode: ");
> + if ( !(bd->mode & BUILD_MODE_PARAVIRT) )
>
> + {
> + if ( bd->mode & BUILD_MODE_ENABLE_DM )
>
> + printk("HVM\n");
> + else
> + printk("PVH\n");
> + }
> + else
> + printk("PV\n");
> + }
> }
I would re-write so the positive condition is processed first, e.g.:
if ( bd->mode & BUILD_MODE_PARAVIRT )
printk("PV\n");
else if ( bd->mode & BUILD_MODE_ENABLE_DM )
printk("HVM\n");
else
printk("PVH\n");
I think it will reduce indentation and make code block a bit easier to read.
Also, if there are more uses for printing string representation of a
boot module mode in the future, perhaps move it to a separate function?
What do you think?
>
> fdt_for_each_subnode(node, fdt, dom_node)
> diff --git a/xen/arch/x86/include/asm/boot-domain.h
> b/xen/arch/x86/include/asm/boot-domain.h
> index d7c6042e25..e316d4bcde 100644
> --- a/xen/arch/x86/include/asm/boot-domain.h
> +++ b/xen/arch/x86/include/asm/boot-domain.h
> @@ -13,6 +13,11 @@
> struct boot_domain {
> domid_t domid;
>
> + /* On | Off /
> +#define BUILD_MODE_PARAVIRT (1 << 0) / PV | PVH/HVM /
> +#define BUILD_MODE_ENABLE_DM (1 << 1) / HVM | PVH */
> + uint32_t mode;
> +
> struct boot_module *kernel;
> struct boot_module *module;
> const char *cmdline;
> diff --git a/xen/arch/x86/setup.c b/xen/arch/x86/setup.c
> index db7280225e..4127a0105d 100644
> --- a/xen/arch/x86/setup.c
> +++ b/xen/arch/x86/setup.c
> @@ -1020,7 +1020,8 @@ static struct domain *__init create_dom0(struct
> boot_info *bi)
> struct boot_domain *bd = &bi->domains[0];
>
> struct domain *d;
>
> - if ( opt_dom0_pvh )
> + if ( opt_dom0_pvh ||
> + (bi->hyperlaunch_enabled && !(bd->mode & BUILD_MODE_PARAVIRT)) )
>
> {
> dom0_cfg.flags |= (XEN_DOMCTL_CDF_hvm |
> ((hvm_hap_supported() && !opt_dom0_shadow) ?
> --
> 2.43.0
