Hi Ralf, *,
On Wed, Apr 24, 2002 at 03:03:15PM -0700, Jun Sun wrote:
> Looks like the infamous cache aliasing problem. Steve Longerbeam had a
> patch which may help. Please try it and let me know the results.
> Maurice Turcotte wrote:
> >I am having a problem with Linux Kernel 2.4.5 on a mips.
> >
> >I have two processes using share memory for IPC. This same
> >code works fine with Kernel 2.4.7 on a x86. The problem is
> >that the second process reads old data out of the shared
> >memory.
> >
> >The executive summary->
> >
> >Process #1 writes "A" to shared memory at 0x2aac7210
> >Process #2 reads 0 from shared memory at address 0x2aaca210
> >Process #1 writes "B" to shared memory at 0x2aac7210
> >Process #2 read "A" from shared memory at address 0x2aaca210
> >Process #1 writes "C" to shared memory at 0x2aac7210
> >Process #2 read "B" from shared memory at address 0x2aaca210
> >
I today tried the patch in conjunction with XFree86 and XSHM on
an Indy R5000/150. Usually all gtk shared-pixmaps get destroyed
and written lines in it. With this patch all these garbage disappears.
As long as there a no serious issues against this patch i would
vote for inclused. It applies against todays cvs with only little
offsets and gave me no problems. It definitly solves some serious
issues with shm.
Flo
--
Florian Lohoff flo@rfc822.org +49-5201-669912
Nine nineth on september the 9th Welcome to the new billenium
cache-alias.patch
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