Hi Jens, On Thu, 31 Jan 2008 19:16:54 +0100, Jens Axboe wrote: > On 31/01/2008, at 18.04, Kiyoshi Ueda <k-ueda@xxxxxxxxxxxxx> wrote: > > On Thu, 31 Jan 2008 14:05:58 +0100, Jens Axboe wrote: > >> On Thu, Jan 31 2008, Nai Xia wrote: > >>> My dmesg relevant info is quite similar: > >>> > >>> [ 6.875041] Freeing unused kernel memory: 320k freed > >>> [ 8.143120] ide-cd: rq still having bio: dev hdc: type=2, > >>> flags=114c8 > >>> [ 8.144439] > >>> [ 8.144439] sector 10824201199534213, nr/cnr 0/0 > >>> [ 8.144439] bio cf029280, biotail cf029280, buffer 00000000, data > >>> 00000000, len 158 > >>> [ 8.144439] cdb: 12 00 00 00 fe 00 00 00 00 00 00 00 00 00 00 00 > >>> [ 8.144439] backup: data_len=158 bi_size=158 > >>> [ 8.160756] ide-cd: rq still having bio: dev hdc: type=2, > >>> flags=114c8 > >>> [ 8.160756] > >>> [ 8.160756] sector 2669858, nr/cnr 0/0 > >>> [ 8.160756] bio cf029300, biotail cf029300, buffer 00000000, data > >>> 00000000, len 158 > >>> [ 8.160756] cdb: 12 01 00 00 fe 00 00 00 00 00 00 00 00 00 00 00 > >>> [ 8.160756] backup: data_len=158 bi_size=158 > >>> [ 14.851101] eth0: link up > >>> [ 27.121883] eth0: no IPv6 routers present > >>> > >>> > >>> And by the way, Kiyoshi, > >>> This can be reproduced in a typical setup vmware workstation 6.02 > >>> with > >>> a vritual IDE cdrom, > >>> in case you wanna catch that with your own eyes. :-) > >>> Thanks for your trying hard to correct this annoying bug. > >> > >> The below fix should be enough. It's perfectly legal to have leftover > >> byte counts when the drive signals completion, happens all the time > >> for eg user issued commands where you don't know an exact byte count. > >> > >> diff --git a/drivers/ide/ide-cd.c b/drivers/ide/ide-cd.c > >> index 74c6087..bee05a3 100644 > >> --- a/drivers/ide/ide-cd.c > >> +++ b/drivers/ide/ide-cd.c > >> @@ -1722,7 +1722,7 @@ static ide_startstop_t cdrom_newpc_intr > >> (ide_drive_t *drive) > >> */ > >> if ((stat & DRQ_STAT) == 0) { > >> spin_lock_irqsave(&ide_lock, flags); > >> - if (__blk_end_request(rq, 0, 0)) > >> + if (__blk_end_request(rq, 0, rq->data_len)) > >> BUG(); > >> HWGROUP(drive)->rq = NULL; > >> spin_unlock_irqrestore(&ide_lock, flags); > > > > OK, I undarstand the leftover is legal. > > > > By the way, is it safe to always return success if there is a > > leftover? > > I thought we might have to complete the rq with -EIO in such case. > > data_len being non zero should pass the residual count back to the > issuer. Aah, so the issuer can know how many bytes of the I/Os are not done, and the error status of the bio which is completed by end_that_request_first() in __blk_end_request() don't matter for the issuer. OK, thanks. I think the patch is fine. Thanks, Kiyoshi Ueda - To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html