On Thursday 20 November 2008 23:28, Dmitry Adamushko wrote: > 2008/11/20 Nick Piggin <nickpiggin@xxxxxxxxxxxx>: > > [ ... ] > > > > - The page is sent to the block layer, which stores into the page. Some > > block devices like 'brd' will potentially store via the kernel linear > > map here, and they probably don't do enough cache flushing. > > btw., if someone is curious, here is another case of what may happen > on VIPT systems when someone uses a "virtual" block device (like > 'brd') as, heh, a swap :-) > > http://www.linux-mips.org/archives/linux-mips/2008-11/msg00038.html Right... Now I'm lacking knowledge when it comes to devices, but I think it is probably reasonable for the block device layer to ensure the physical memory is uptodate after it signals request completion. That is, there shouldn't be any potentially aliasing dirty lines. Block devices which do any writeout via the kernel linear address (eg. brd) should do a flush_dcache_page. -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
