Messages in this thread | | | Date | Tue, 21 Sep 2010 16:19:50 -0700 | From | Andrew Morton <> | Subject | Re: [PATCH] fbmem: Fix fb_read, fb_write unaligned accesses. |
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On Sat, 18 Sep 2010 01:23:47 +0100 James Hogan <james@albanarts.com> wrote:
> Apologies for corrupted patch. I'll try again. > Comments? I'd also appreciate if somebody familiar with sbus on sparc > could check this patch is sane since I know virtually nothing about sbus > and am not in a position to compile for sparc, let alone test on it: > > fb_{read,write} access the framebuffer using lots of fb_{read,write}l's > but don't check that the file position is aligned which can cause > problems on some architectures which do not support unaligned accesses.
What are these "problems"?
I'd have thought they would be fairly fatal, in which case this is a high-priority patch. But I'd also have thought that the problems would have been noted before now.
So I assume that you're doing something which nobody has done before.
Confused. Help?
> Since the operations are essentially memcpy_{from,to}io, new > fb_memcpy_{from,to}fb macros have been defined and these are used > instead. > > For Sparc, fb_{read,write} macros use sbus_{read,write}, so this defines > new sbus_memcpy_{from,to}io functions the same as memcpy_{from,to}io but > using sbus_{read,write}b instead of {read,write}b.
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