Messages in this thread |  | | | Date | Tue, 26 Feb 2008 15:08:45 -0800 | | From | Andrew Morton <> | | Subject | Re: regression: CD burning (k3b) went broke | |
On Tue, 26 Feb 2008 14:36:43 +0100 Mike Galbraith <efault@gmx.de> wrote:
> > On Tue, 2008-02-26 at 10:48 +0100, Mike Galbraith wrote:
> > Greetings,> > > > I straced both a good and a bad kernel (good being .git with attached
> > revert patch applied) and filtered/diffed/merged the output. Scroll
> > down to "HERE" to see the problem (resid).
> >
> > I'm poking around, but not having much luck.
cc's added.
I'm told this is part of "Tejun's DMA drain handling".
> Seems the problem is data_len changes, but raw_data_len doesn't. I've
> not the foggiest IO-land clue, but k3b works again, so the below may
> have some diagnostic value.
So this change fixes a bug? Can we have a recap of how it does this?
> diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
> index ba21d97..7a6f784 100644> --- a/drivers/scsi/scsi_lib.c> +++ b/drivers/scsi/scsi_lib.c> @@ -871,7 +871,7 @@ void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes)
> scsi_end_bidi_request(cmd);
> return;
> }
> - req->data_len = scsi_get_resid(cmd);
> + req->data_len = req->raw_data_len = scsi_get_resid(cmd);
> }
>
> BUG_ON(blk_bidi_rq(req)); /* bidi not support for !blk_pc_request yet */
>
Thanks.
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