Re: 2.6.34-rc1 eat my photo SD card :-(

[Jens Axboe <jens.axboe@oracle.com>]

On Wed, Nov 07 2007, Roland Dreier wrote:
>  > Well, I spent the last 36 hours (more or less) trying to bisect the SD
>  > problem. The method I used was to insert the card, umount it, and make 8 dd
>  > in a row; the kernel is "bad" if they differs, "good" if they are the same. 
>  > 
>  > I could not finish the bisect. The last pair good/bad were:
>  > 
>  > bad:   [7aeacf982203fb4dea2f3434eefdc268cfd5d6d9] 
>  >        [BLOCK] blk_rq_map_sg: force clear termination bit
>  > good:  [e38f981758118d829cd40cfe9c09e3fa81e422aa] 
>  >        exportfs: update documentation
> 
> Thanks, that helps.  I read over the mmc changes in between those two
> commits, and I think I found the problem... could you please try the
> patch below (on top of the latest kernel) and report back how it
> works?  Unfortunately I am traveling and I don't have an SD card with
> me to test on my laptop...
> 
> Pierre, assuming Romano tests this patch successfully, please apply!
> 
> Thanks,
>   Roland
> 
> <-- patch below -->
> 
> mmc: Fix sg helper copy-and-paste error
> 
> Commit 45711f1a ("[SG] Update drivers to use sg helpers") had the
> following bogus change in drivers/mmc/card/queue.c:
> 
>     > -			src_buf = page_address(src->page) + src->offset;
>     > +			src_buf = sg_virt(dst);
> 
> (Notice that "src" is converted to "dst").  Turn this "dst" back into
> the intended "src".
> 
> Cc: Jens Axboe <jens.axboe@oracle.com>
> Signed-off-by: Roland Dreier <roland@digitalvampire.org>
> ---
> diff --git a/drivers/mmc/card/queue.c b/drivers/mmc/card/queue.c
> index 9203a0b..1b9c9b6 100644
> --- a/drivers/mmc/card/queue.c
> +++ b/drivers/mmc/card/queue.c
> @@ -310,7 +310,7 @@ static void copy_sg(struct scatterlist *dst, unsigned int dst_len,
>  		}
>  
>  		if (src_size == 0) {
> -			src_buf = sg_virt(dst);
> +			src_buf = sg_virt(src);
>  			src_size = src->length;
>  		}
>  

How embarassing, sorry about that! Pierre, shall I shove this upstream
or will you?

-- 
Jens Axboe