On Tue, Sep 01, 2009 at 03:43:48PM +0200, Laurent Pinchart wrote: > I might be missing something obvious, but I fail to see how VIVT caches > could work at all with multiple mappings. If a kernel-allocated buffer > is DMA'ed to, we certainly want to invalidate all cache lines that store > buffer data. As the cache doesn't care about physical addresses we thus > need to invalidate all virtual mappings for the buffer. If the buffer is > mmap'ed in userspace I don't see how that would be done. You need to ask MM gurus about that. I don't touch the Linux MM very often so tend to keep forgetting how it works. However, it does work for shared mappings of files on CPUs with VIVT caches. -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
