lkml.org 
[lkml]   [2005]   [Nov]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
SubjectRe: Linux 2.6.14: Badness in as-iosched
On Mon, Nov 21 2005, Brice Goglin wrote:
> Jens Axboe wrote:
>
> >On Thu, Nov 10 2005, Brice Goglin wrote:
> >
> >
> >>Hi Jens,
> >>
> >>I just hit a badness (actually, tons of badness like this) in as-iosched
> >>while ripping
> >>an audio CD with ripperX (with cdparanoia as a backend).
> >>I was using 2.6.14 on an IBM Thinkpad R52. The kernel has been compiled with
> >>gcc-4.0.2-2 (Debian testing).
> >>
> >>The first badness in dmesg is:
> >>
> >>cdrom: dropping to single frame dma
> >>arq->state: 4
> >>Badness in as_insert_request at drivers/block/as-iosched.c:1519
> >> [<c0237410>] as_insert_request+0x70/0x1d0
> >> [<c022dc25>] __elv_add_request+0xa5/0xe0
> >> [<c022dc8b>] elv_add_request+0x2b/0x40
> >> [<c0230fe6>] blk_execute_rq_nowait+0x46/0x60
> >> [<c023107a>] blk_execute_rq+0x7a/0xe0
> >> [<c0231310>] blk_end_sync_rq+0x0/0x30
> >> [<c0160b77>] bio_phys_segments+0x27/0x30
> >> [<c0232610>] blk_rq_bio_prep+0x40/0xb0
> >> [<c0230dc7>] blk_rq_map_user+0xb7/0xf0
> >> [<c026bc32>] cdrom_read_cdda_bpc+0x182/0x210
> >> [<c026bd1b>] cdrom_read_cdda+0x5b/0xc0
> >>
> >>
> >
> >Similar case was posted yesterday (I realize yours is older, just missed
> >it the first time around), see my explanation here:
> >
> >http://lkml.org/lkml/2005/11/20/119
> >
> >And work-around below.
> >
> >
> Thank you very much, Jens.
> Is this patch going to -stable ?

Probably just killing the 'as' printk is a lot better for -stable.

Signed-off-by: Jens Axboe <axboe@suse.de>

--- linux-2.6.14/drivers/block/as-iosched.c~ 2005-11-21 16:38:36.000000000 +0100
+++ linux-2.6.14/drivers/block/as-iosched.c 2005-11-21 16:39:07.000000000 +0100
@@ -1513,13 +1513,8 @@
struct as_data *ad = q->elevator->elevator_data;
struct as_rq *arq = RQ_DATA(rq);

- if (arq) {
- if (arq->state != AS_RQ_PRESCHED) {
- printk("arq->state: %d\n", arq->state);
- WARN_ON(1);
- }
+ if (arq)
arq->state = AS_RQ_NEW;
- }

/* barriers must flush the reorder queue */
if (unlikely(rq->flags & (REQ_SOFTBARRIER | REQ_HARDBARRIER)
--
Jens Axboe

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-11-21 16:41    [W:0.035 / U:0.072 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site