Re: framebuffer corruption due to overlapping stp instructions on arm64

Catalin Marinas
2018-08-08T14:50:25Z

On Wed, Aug 08, 2018 at 02:26:11PM +0000, David Laight wrote:
> From: Mikulas Patocka
> > Sent: 08 August 2018 14:47
> ...
> > The problem on ARM is that I see data corruption when the overlapping
> > unaligned writes are done just by a single core.
>
> Is this a sequence of unaligned writes (that shouldn't modify the
> same physical locations) or an aligned write followed by an
> unaligned one that updates part of the earlier write.
> (Or the opposite order?)

In the memcpy() case, there can be a sequence of unaligned writes but
they would not modify the same byte (so no overlapping address at the
byte level).

--
Catalin