From mboxrd@z Thu Jan 1 00:00:00 1970 From: Laurent Pinchart Date: Thu, 23 Oct 2014 23:50:42 +0000 Subject: Re: [PATCH 2/4] mm: cma: Always consider a 0 base address reservation as dynamic Message-Id: <3165257.hQsT1mEnTD@avalon> List-Id: References: <1414074828-4488-1-git-send-email-laurent.pinchart+renesas@ideasonboard.com> <1414074828-4488-3-git-send-email-laurent.pinchart+renesas@ideasonboard.com> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-arm-kernel@lists.infradead.org Hi Michal, On Thursday 23 October 2014 18:55:20 Michal Nazarewicz wrote: > 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 > > > > Acked-by: Michal Nazarewicz > > And like before, this should also probably also go to stable. v3.17 and older don't have the extra fixed checks, so I don't think there's a need to Cc 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; -- Regards, Laurent Pinchart