Re: [PATCH] x86: consider modules when cutting off memory

[Keir Fraser <keir.xen@gmail.com>]

On 18/11/2013 00:37, "Jan Beulich" <JBeulich@suse.com> wrote:

> The code in question runs after module ranges got already removed from
> the E820 table, so when determining the new maximum page/PDX we need to
> explicitly take them into account.
> 
> Furthermore we need to round up the ending addresses here, in order to
> fully cover eventual partial trailing pages.

Is rounding up the right thing to do? We round down in find_max_pfn()?

> Signed-off-by: Jan Beulich <jbeulich@suse.com>
> 
> --- a/xen/arch/x86/setup.c
> +++ b/xen/arch/x86/setup.c
> @@ -1013,9 +1013,17 @@ void __init __start_xen(unsigned long mb
>                      ASSERT(j);
>                  }
>                  map_e = boot_e820.map[j].addr + boot_e820.map[j].size;
> -                if ( (map_e >> PAGE_SHIFT) < max_page )
> +                for ( j = 0; j < mbi->mods_count; ++j )
>                  {
> -                    max_page = map_e >> PAGE_SHIFT;
> +                    uint64_t end = pfn_to_paddr(mod[j].mod_start) +
> +                                   mod[j].mod_end;
> +
> +                    if ( map_e < end )
> +                        map_e = end;
> +                }
> +                if ( PFN_UP(map_e) < max_page )
> +                {
> +                    max_page = PFN_UP(map_e);
>                      max_pdx = pfn_to_pdx(max_page - 1) + 1;
>                  }
>                  printk(XENLOG_WARNING "Ignoring inaccessible memory range"
> 
> 
>