Re: css hang; somewhere between test12 and test13pre4ac2

[Jens Axboe <axboe@suse.de>]

[-- Attachment #1: Type: text/plain, Size: 1090 bytes --]

On Mon, Dec 25 2000, Dave Gilbert wrote:
> > The most likely suspect (as someone else pointed out) is not at
> > all css (I'm not even sure what you mean by css hang?) but UDF.
> 
> I mean a complete system hang when playing a CSS disc - doesn't even ping.
> Doesn't recover.

Hmm

> > Given the fs changes. Since sysrq still works, it would help a
> > lot if you could capture sysrq-p repeatedly and send it in.
> 
> I think at this point the only thing that works is sysrq-b - at least the
> sysrq-u's and sysrq-s's that I've given don't seem to have cleanly
> unmounted the file system.

Could you at least check? You may need some sort of serial console too..

> > Do you have any non-css discs to beat on UDF?
> 
> Yep one disc (Scanners) - it is fine - hence my reason for beleiving it is
> a CSSism (although I guess CSS makes other demands on the UDF code).

Not so. Once a css "session" has been established, data is read just
like off any other CD. But try with this patch applied, it could be
a NULL pointer deref at the wrong time.

-- 
* Jens Axboe <axboe@suse.de>
* SuSE Labs

[-- Attachment #2: idecd_log-2 --]
[-- Type: text/plain, Size: 268 bytes --]

--- drivers/ide/ide-cd.c~	Sat Dec 23 23:59:52 2000
+++ drivers/ide/ide-cd.c	Sun Dec 24 00:03:38 2000
@@ -333,7 +333,7 @@
 {
 	int log = 0;
 
-	if (sense == NULL || pc->quiet)
+	if (sense == NULL || pc == NULL || pc->quiet)
 		return 0;
 
 	switch (sense->sense_key) {