Re: [PATCH] xen: arm: don't release modules which aren't in RAM into the heap

[Julien Grall <julien.grall@linaro.org>]

Hi Ian,

On 23/07/14 17:45, Ian Campbell wrote:
> They might be in e.g. flash or something but more likely they could
> bein a bank of RAM which we aren't handling or in RAM which the

being?

> bootloader hasn't told us about for some reason.
>
> Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
> Cc: Fu Wei <fu.wei@linaro.org>
> Cc: Roy Franz <roy.franz@linaro.org>
> ---
>   xen/arch/arm/setup.c |    9 +++++++--
>   1 file changed, 7 insertions(+), 2 deletions(-)
>
> diff --git a/xen/arch/arm/setup.c b/xen/arch/arm/setup.c
> index e53e491..446b4dc 100644
> --- a/xen/arch/arm/setup.c
> +++ b/xen/arch/arm/setup.c
> @@ -247,8 +247,13 @@ void __init discard_initial_modules(void)
>           paddr_t s = mi->module[i].start;
>           paddr_t e = s + PAGE_ALIGN(mi->module[i].size);
>
> -        if ( mi->module[i].kind != BOOTMOD_XEN )
> -            dt_unreserved_regions(s, e, init_domheap_pages, 0);
> +        if ( mi->module[i].kind == BOOTMOD_XEN )
> +            continue;
> +
> +        if ( !mfn_valid(paddr_to_pfn(s)) || !mfn_valid(paddr_to_pfn(e)))
> +            continue;

What happen if the bootloader decide to put the module between 2 banks 
and having the hole in the middle. Such as:

start of the module

end of bank 0

hole

start of bank 1

end of the module

Regards,

-- 
Julien Grall