Re: [PATCH v2 34/39] xen/riscv: restore register state in the new IMSIC VS-file

[Jan Beulich <jbeulich@xxxxxxxx>]

On 27.08.2026 17:21, Oleksii Kurochko wrote:
> @@ -630,13 +649,13 @@ static void cf_check imsic_vsfile_local_read_clear(void 
> *data)
>      old_vsiselect = csr_read(CSR_VSISELECT);
>      old_hstatus = csr_read(CSR_HSTATUS);
>      new_hstatus = old_hstatus & ~HSTATUS_VGEIN;
> -    new_hstatus |= ((unsigned long)idata->hgei) << HSTATUS_VGEIN_SHIFT;
> +    new_hstatus |= MASK_INSR(idata->hgei, HSTATUS_VGEIN);

Please put into final shape upon introduction.

>      csr_write(CSR_HSTATUS, new_hstatus);
>  
>      /*
> -     * There is no need to use atomic functions version to store
> -     * values in MRIF because imsic_vsfile_read_clear() is always called
> -     * with pointer to temporary MRIF on stack.
> +     * No atomic accessors are needed to store the values into the MRIF here,
> +     * as imsic_vsfile_read_clear() is always called with a pointer to a
> +     * temporary MRIF on the stack.
>       */

Same for this comment perhaps.

> @@ -1077,5 +1140,12 @@ void imsic_migrate_vcpu(struct vcpu *v)
>      /* Free-up old IMSIC VS-file */
>      vgein_release(v, old_vsfile_id, old_vsfile_cpu);
>  
> -    BUG_ON("unimplemented");
> +    /* Restore register state in the new IMSIC VS-file */
> +    vsfile_data.mrif = &tmrif;

Ah, here &tmrif is used a 2nd time.

> +    imsic_call_on_cpu(new_vsfile_cpu, imsic_vsfile_local_update, 
> &vsfile_data);
> +
> +    /* Set VCPU HSTATUS.VGEIN to new IMSIC VS-file */
> +    vcpu_guest_cpu_user_regs(v)->hstatus &= ~HSTATUS_VGEIN;
> +    vcpu_guest_cpu_user_regs(v)->hstatus |=
> +            MASK_INSR(new_vsfile_hgei, HSTATUS_VGEIN);

Nit: Indentation.

Other comments on earlier patches apply here (and possibly elsewhere) as
well. Just ftaod.

Jan