Messages in this thread | | | Date | Mon, 22 Aug 2016 11:06:01 +0200 | From | Thierry Reding <> | Subject | Re: [PATCH 2/4] arm64: defconfig: Set cma heap size to 128MB |
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On Fri, Aug 19, 2016 at 11:42:06PM +0800, Guodong Xu wrote: > From: Xinliang Liu <xinliang.liu@linaro.org> > > For debian linux, cma heap is used to allocate graphic buffers. > The default size is 16 MB which is not enought. > So increase the size to 128 MB. > > Signed-off-by: Xinliang Liu <xinliang.liu@linaro.org> > --- > arch/arm64/configs/defconfig | 1 + > 1 file changed, 1 insertion(+)
This is a bad idea. You're increasing this heap for all users of the default configuration (which on 64-bit ARM is everyone, really). Many of the devices don't require the CMA except maybe for the occasional very small buffer. Most implement some form of IOMMU support that removes the need for large amounts of contiguous physical memory.
I think it's a better idea to have some bootloader append a cma=128 to the kernel command-line if necessary.
Thierry [unhandled content-type:application/pgp-signature] | |