Re: [PATCH 2/4] mm: cma: Always consider a 0 base address reservation as dynamic

From: Michal Nazarewicz
Date: Thu Oct 23 2014 - 12:55:32 EST


On Thu, Oct 23 2014, Laurent Pinchart wrote:
> The fixed parameter to cma_declare_contiguous() tells the function
> whether the given base address must be honoured or should be considered
> as a hint only. The API considers a zero base address as meaning any
> base address, which must never be considered as a fixed value.
>
> Part of the implementation correctly checks both fixed and base != 0,
> but two locations check the fixed value only. Set fixed to false when
> base is 0 to fix that and simplify the code.
>
> Signed-off-by: Laurent Pinchart
> <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx>

Acked-by: Michal Nazarewicz <mina86@xxxxxxxxxx>

And like before, this should also probably also go to stable.

> ---
> mm/cma.c | 5 ++++-
> 1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/mm/cma.c b/mm/cma.c
> index 16c6650..6b14346 100644
> --- a/mm/cma.c
> +++ b/mm/cma.c
> @@ -239,6 +239,9 @@ int __init cma_declare_contiguous(phys_addr_t base,
> size = ALIGN(size, alignment);
> limit &= ~(alignment - 1);
>
> + if (!base)
> + fixed = false;
> +
> /* size should be aligned with order_per_bit */
> if (!IS_ALIGNED(size >> PAGE_SHIFT, 1 << order_per_bit))
> return -EINVAL;
> @@ -262,7 +265,7 @@ int __init cma_declare_contiguous(phys_addr_t base,
> }
>
> /* Reserve memory */
> - if (base && fixed) {
> + if (fixed) {
> if (memblock_is_region_reserved(base, size) ||
> memblock_reserve(base, size) < 0) {
> ret = -EBUSY;
> --
> 2.0.4
>

--
Best regards, _ _
.o. | Liege of Serenely Enlightened Majesty of o' \,=./ `o
..o | Computer Science, MichaÅ âmina86â Nazarewicz (o o)
ooo +--<mpn@xxxxxxxxxx>--<xmpp:mina86@xxxxxxxxxx>--ooO--(_)--Ooo--
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/