Re: [PATCH] xen/arm: Workaround for memory problem >1gb on last section

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

Hi Frediano,

In general, we add in the subject the version of the subject (for
instance [PATCH v3]).

Sorry to ask you few others changes. The title doesn't seem suitable,
it's not a workaround (it would mean it's temporary) but an error in the
code.

On 10/02/2014 03:07 PM, Frediano Ziglio wrote:
> setup_xenheap_mappings setup head memory on Arm 32 has a limit of 1gb.
> On system with large memory is possible that there are no blocks of memory
> smaller than 1gb leading xenheap_pages to be more than 1gb.
> This cause memory errors trying to access heap after the 1gb limit.
> 
> Signed-off-by: Frediano Ziglio <frediano.ziglio@huawei.com>
> ---
>  xen/arch/arm/setup.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/xen/arch/arm/setup.c b/xen/arch/arm/setup.c
> index 446de8a..e223d1b 100644
> --- a/xen/arch/arm/setup.c
> +++ b/xen/arch/arm/setup.c
> @@ -509,6 +509,7 @@ static void __init setup_mm(unsigned long
> dtb_paddr, size_t dtb_size)
>      heap_pages = ram_pages;
>      xenheap_pages = (heap_pages/8 + 0x1fffUL) & ~0x1fffUL;
>      xenheap_pages = max(xenheap_pages, 128UL<<(20-PAGE_SHIFT));
> +    xenheap_pages = min(xenheap_pages, 1UL<<(30-PAGE_SHIFT));

Can you also update the comment above, saying we are requesting at most 1G?

With this 2 minors changes:

Reviewed-by: Julien Grall <julien.grall@linaro.org>

Regards,

-- 
Julien Grall