Re: [PATCH 04/16] x86/srat: vmap the pages for acpi_slit

[Jan Beulich <jbeulich@xxxxxxxx>]

On 30.04.2020 22:44, Hongyan Xia wrote:
> --- a/xen/arch/x86/srat.c
> +++ b/xen/arch/x86/srat.c
> @@ -196,7 +196,8 @@ void __init acpi_numa_slit_init(struct acpi_table_slit 
> *slit)
>               return;
>       }
>       mfn = alloc_boot_pages(PFN_UP(slit->header.length), 1);
> -     acpi_slit = mfn_to_virt(mfn_x(mfn));
> +     acpi_slit = vmap_boot_pages(mfn, PFN_UP(slit->header.length));
> +     BUG_ON(!acpi_slit);
>       memcpy(acpi_slit, slit, slit->header.length);
>  }

I'm not sure in how far this series is still to be considered
active / pending; I still have it in my inbox as something to
look at in any event. If it is, then I think the latest by this
patch it becomes clear that we either want to make vmalloc()
boot-allocator capable, or introduce e.g. vmalloc_boot().
Having this recurring pattern including the somewhat odd
vmap_boot_pages() is imo not the best way forward. It would
then also no longer be necessary to allocate contiguous pages,
as none of the users up to here appear to have such a need.

Jan