Re: framebuffer corruption due to overlapping stp instructions on arm64

Florian Weimer
2018-08-03T07:53:56Z

On 08/03/2018 09:11 AM, Andrew Pinski wrote:
> Yes fix Links not to use memcpy on the framebuffer.
> It is undefined behavior to use device memory with memcpy.

Some (de facto) ABIs require that it is supported, though. For example,
the POWER string functions avoid unaligned loads and stores for this
reason because the platform has the same issue with device memory. And
yes, GCC will expand memcpy on POWER to something that is incompatible
with device memory. 8-(

If we don't want people to use memcpy, we probably need to provide a
credible alternative.

Thanks,
Florian