Subject: Re: port-arm/36513: Pre-cache load length exceeds source memory area in memcpy
To: None <scw@NetBSD.org, gnats-admin@netbsd.org, netbsd-bugs@netbsd.org,>
From: Steve Woodford <scw@netbsd.org>
List: netbsd-bugs
Date: 06/20/2007 08:05:07
The following reply was made to PR port-arm/36513; it has been noted by GNATS.

From: Steve Woodford <scw@netbsd.org>
To: gnats-bugs@netbsd.org
Cc: port-arm-maintainer@netbsd.org, gnats-admin@netbsd.org,
	netbsd-bugs@netbsd.org
Subject: Re: port-arm/36513: Pre-cache load length exceeds source memory area in memcpy
Date: Wed, 20 Jun 2007 09:03:32 +0100

 On Wednesday 20 June 2007 03:15, Hiroki Doshita wrote:
 
 > Pre-cache load length exceeds source memory area in memcpy.
 > Unrelated area is written back to memory, which causes
 > some troubles.
 
 Can you elaborate on the "some troubles" part? The source cacheline will 
 not be marked dirty by pld, assuming it was already clean or not 
 resident in the cache to begin with, so a write-back will not occur.
 
 The only case I can think of where this *may* be an issue would be 
 copying from a cacheable memory region which is shared with a 
 DMA-capable device...
 
 Cheers, Steve