Re: [PATCH v3 04/23] xen/riscv: Implement construct_domain()

[Oleksii Kurochko <oleksii.kurochko@xxxxxxxxx>]

On 6/17/26 1:26 PM, Jan Beulich wrote:
> On 17.06.2026 13:17, Oleksii Kurochko wrote:
> > Implement construct_domain() function for RISC-V, which performs initial setup
> > for the domain's first vCPU, loads the kernel, initrd, and device tree,
> > and sets up guest CPU registers for boot.
> >
> > It also creates additional vCPUs up to max_vcpus and assigns the device tree
> > address and boot cpuid in registers.
> >
> > Signed-off-by: Oleksii Kurochko <oleksii.kurochko@xxxxxxxxx>
> > ---
> > Changes in v3:
> >   - s/%d/%u for printing vCPU index in the failure message.
> >   - Drop dprintk() for successful vCPU creation.
> My
>
> Acked-by: Jan Beulich <jbeulich@xxxxxxxx>
>
> was lost, however. One more remark:
>
> > --- /dev/null
> > +++ b/xen/arch/riscv/domain-build.c
> > @@ -0,0 +1,50 @@
> > +/* SPDX-License-Identifier: GPL-2.0-or-later */
> > +
> > +#include <xen/fdt-domain-build.h>
> > +#include <xen/fdt-kernel.h>
> > +#include <xen/init.h>
> > +#include <xen/sched.h>
> > +
> > +#include <asm/current.h>
> > +#include <asm/guest_access.h>
> > +
> > +int __init construct_domain(struct domain *d, struct kernel_info *kinfo)
> > +{
> > +    struct vcpu *v = d->vcpu[0];
> > +    struct cpu_user_regs *regs = vcpu_guest_cpu_user_regs(v);
> > +
> > +    BUG_ON(v->is_initialised);
> > +
> > +    /*
> > +     * At the moment *_load() don't return value and will just panic()
> > +     * inside.
> > +     * TODO: it will be good to change that.
> > +     */
> > +    kernel_load(kinfo);
> > +    initrd_load(kinfo, copy_to_guest_phys);
> > +    dtb_load(kinfo, copy_to_guest_phys);
> > +
> > +    regs->sepc = kinfo->entry;
> > +
> > +    /* Guest boot cpuid = 0 */
> > +    regs->a0 = 0;
> > +    regs->a1 = kinfo->dtb_paddr;
> > +
> > +    for ( unsigned int i = 1; i < d->max_vcpus; i++ )
> > +    {
> > +        const struct vcpu *tmp_v = vcpu_create(d, i);
> > +
> > +        if ( !tmp_v )
> > +        {
> > +            printk("Failed to allocate %pd v%u\n", d, i);
> If you dropped the blank before v%u, the output would match that of %pv
> (improving the chances of people actually spotting that the exact same
> thing is meant). Once again - can do the adjustment while committing,
> provided you agree (and provided earlier patches gain the necessary
> acks).
I will be happy with that.

Thanks.

~ Oleksii