On Tue, 19 Dec 2006 03:44:51 +0200 Andrei Popa <[EMAIL PROTECTED]> wrote:
> On Mon, 2006-12-18 at 17:21 -0800, Andrew Morton wrote: > > On Mon, 18 Dec 2006 16:57:30 -0800 (PST) > > Linus Torvalds <[EMAIL PROTECTED]> wrote: > > > > > What happens if you only ifdef out that single thing? > > > > > > The actual page-cleaning functions make sure to only clear the TAG_DIRTY > > > bit _after_ the page has been marked for writeback. Is there some > > > ordering > > > constraint there, perhaps? > > > > > > I'm really reaching here. I'm trying to see the pattern, and I'm not > > > seeing it. I'm asking you to test things just to get more of a feel for > > > what triggers the failure, than because I actually have any kind of idea > > > of what the heck is going on. > > > > > > Andrew, Nick, Hugh - any ideas? > > > > If all of test_clear_page_dirty() has been commented out then the page will > > never become clean hence will never fall out of pagecache, so unless Andrei > > is doing a reboot before checking for corruption, perhaps the underlying > > data on-disk is incorrect, but we can't see it. > > if I do a sync and echo 1 > /proc/sys/vm/drop_caches OK, that works. > does the reboot is > still necesary ? It might be necessary to reboot in this case - if we're leaving the pagecache dirty, writing to drop_caches won't remove it. And you probably won't be able to get a clean reboot either. > > > > Andrei, how _are_ you running this test? What's the exact sequence of > > steps? > > > > In particular, are you doing anything which would cause the corrupted file > > to be evicted from memory, thus forcing a read from disk? Such as > > unmounting and then remounting the filesystem? > > I boot linux, I start rtorrent and start the download, while it's > downloading I start evolution and i check my mail(my mbox is very large, > several hundered megabytes), I close evolution(I use evolution just to > have another application witch uses the filesystem and the memory), I > start evolution again. I start firefox. The download is complete. > Rtorrent says if the hash is good or not. I do a "unrar t qwe.rar" to > test that all 84 downloaded rar files are ok and see the result. > > > > > The point of my question is to check that the data is really incorrect > > on-disk, or whether it is incorrect in pagecache. > > > > Also, it'd be useful if you could determine whether the bug appears with > > the ext2 filesystem: do s/ext3/ext2/ in /etc/fstab, or boot with > > rootfstype=ext2 if it's the root filesystem. > > I will test. ok, thanks. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
