On Tue, Sep 28, 2010 at 23:19, richard -rw- weinberger <richard.weinber...@gmail.com> wrote: > On Tue, Sep 28, 2010 at 10:37 PM, Geert Uytterhoeven > <ge...@linux-m68k.org> wrote: >> >> This changeset from 2007 indeed moved the update of req->sector. >> >> However, in the new code, before or after applying your patch, there's no >> update >> of req->sector anymore. Everything is done in local variables. >> >> Is it possible that we only need the hunk below to fix the corruption? > > Yes, it seems so. So far all my test cases work fine. > I'll submit a patch in a few minutes.
Thanks, good to know! >> | diff --git a/arch/um/drivers/ubd_kern.c b/arch/um/drivers/ubd_kern.c >> | index 5ff5546..655ed9e 100644 >> | --- a/arch/um/drivers/ubd_kern.c >> | +++ b/arch/um/drivers/ubd_kern.c >> | @@ -746,8 +746,12 @@ static int ubd_open_dev(struct ubd *ubd_dev) >> | } >> | ubd_dev->fd = fd; >> | >> | + /* A setting higher than 1 sector currently (v2.6.33) generates >> | + data loss, both for raw and cow ubd. */ >> | + blk_queue_max_sectors(ubd_dev->queue, 1 * sizeof(long)); >> | + blk_queue_max_phys_segments(ubd_dev->queue, 1 * sizeof(long)); >> | + >> | if(ubd_dev->cow.file != NULL){ >> | - blk_queue_max_sectors(ubd_dev->queue, 8 * sizeof(long)); >> | >> | err = -ENOMEM; >> | ubd_dev->cow.bitmap = vmalloc(ubd_dev->cow.bitmap_len); So we can no longer process more than one sector? Why? Could it be 4d6c84d91d1a539ebc47d1a36a35e9390ba11fdc (ubd: cleanup completion path), which is one of the three commits you pointed out? Before 4d6c84d91d1a539ebc47d1a36a35e9390ba11fdc, blk_end_request() was only called when rq->nr_sectors reached zero. Now it's called for each part. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- ge...@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds ------------------------------------------------------------------------------ Start uncovering the many advantages of virtual appliances and start using them to simplify application deployment and accelerate your shift to cloud computing. http://p.sf.net/sfu/novell-sfdev2dev _______________________________________________ User-mode-linux-devel mailing list User-mode-linux-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel