Re: [PATCH v2 5/5] xen/memory, tools: Make init-dom0less consume XEN_DOMCTL_get_mem_map

From: Anthony PERARD <anthony.perard@cloud.com>
To: Henry Wang <xin.wang2@amd.com>
Cc: xen-devel@lists.xenproject.org, Wei Liu <wl@xen.org>,
	Andrew Cooper <andrew.cooper3@citrix.com>,
	George Dunlap <george.dunlap@citrix.com>,
	Jan Beulich <jbeulich@suse.com>, Julien Grall <julien@xen.org>,
	Stefano Stabellini <sstabellini@kernel.org>,
	Alec Kwapis <alec.kwapis@medtronic.com>
Subject: Re: [PATCH v2 5/5] xen/memory, tools: Make init-dom0less consume XEN_DOMCTL_get_mem_map
Date: Mon, 25 Mar 2024 15:35:47 +0000	[thread overview]
Message-ID: <9162a331-645c-4e45-b5d0-57c6b9b4f79b@perard> (raw)
In-Reply-To: <20240308015435.4044339-6-xin.wang2@amd.com>

On Fri, Mar 08, 2024 at 09:54:35AM +0800, Henry Wang wrote:
> diff --git a/tools/helpers/init-dom0less.c b/tools/helpers/init-dom0less.c
> index fee93459c4..92c612f6da 100644
> --- a/tools/helpers/init-dom0less.c
> +++ b/tools/helpers/init-dom0less.c
> @@ -23,16 +23,30 @@ static int alloc_xs_page(struct xc_interface_core *xch,
>                           libxl_dominfo *info,
>                           uint64_t *xenstore_pfn)
>  {
> -    int rc;
> -    const xen_pfn_t base = GUEST_MAGIC_BASE >> XC_PAGE_SHIFT;
> -    xen_pfn_t p2m = (GUEST_MAGIC_BASE >> XC_PAGE_SHIFT) + XENSTORE_PFN_OFFSET;
> +    int rc, i;
> +    xen_pfn_t base = ((xen_pfn_t)-1);
> +    xen_pfn_t p2m = ((xen_pfn_t)-1);
> +    uint32_t nr_regions = XEN_MAX_MEM_REGIONS;
> +    struct xen_mem_region mem_regions[XEN_MAX_MEM_REGIONS] = {0};
> +
> +    rc = xc_get_domain_mem_map(xch, info->domid, mem_regions, &nr_regions);

Shouldn't you check the value of in `rc`?

> +    for ( i = 0; i < nr_regions; i++ )
> +    {
> +        if ( mem_regions[i].type == GUEST_MEM_REGION_MAGIC )
> +        {
> +            base = mem_regions[i].start >> XC_PAGE_SHIFT;
> +            p2m = (mem_regions[i].start >> XC_PAGE_SHIFT) + XENSTORE_PFN_OFFSET;
> +        }
> +    }

Thanks,

-- 
Anthony PERARD