On Tue, 17 Dec 2002, Mikael Pettersson wrote:
> I wrote:
> >On Sun, 15 Dec 2002 02:23:34 +0100, Marc-Christian Petersen wrote:
> >>> Kernel 2.4.21-pre1 broke the ide-tape driver: the driver
> >>> now hangs during initialisation. 2.2 kernels (with Andre's
> >>> IDE patch) and 2.4 up to 2.4.20 do not have this problem.
> >>> My box has a Seagate STT8000A ATAPI tape drive as hdd;
> >>> hdc is a Philips CD-RW, and the controller is ICH2 (i850 chipset).
> >>http://linux.bkbits.net:8080/linux-2.4/patch@1.828?nav=index.html|ChangeSet@-7d|cset@1.828
> >
> >Addendum: this patch fixes the init-time hang, and ide-tape does
> >seem to work fine, but 'rmmod ide-tape' oopses -- 2.4.20-ac2 also
> >oopses on 'rmmod ide-tape'.
>
> Solved, I think. Observe ide-tape's module_exit() procedure idetape_exit():
>
> >static void __exit idetape_exit (void)
> >{
> > ide_drive_t *drive;
> > int minor;
> >
> > for (minor = 0; minor < MAX_HWIFS * MAX_DRIVES; minor++) {
> > drive = idetape_chrdevs[minor].drive;
> > if (drive != NULL && idetape_cleanup(drive))
> > printk(KERN_ERR "ide-tape: %s: cleanup_module() "
> > "called while still busy\n", drive->name);
> > }
> >#ifdef CONFIG_PROC_FS
> > if (drive->proc)
> > ide_remove_proc_entries(drive->proc, idetape_proc);
> >#endif
> >
> > ide_unregister_module(&idetape_module);
> >}
>
> In the "if (drive->proc)" line, drive==NULL when I rmmod ide-tape,
> causing the oops.
>
> I'm not sure if ide_remove_proc_entries() is needed or not,
> but the current code is obviously broken.
>
> - ide_unregister_module() removes ide-tape's proc entry
> (/proc/ide/ideX/hdY/name) for us, at least that's what happens
> on my box after I commented out the entire "if (drive->proc) ..."
> statement to prevent the oops. So possibly the call should be deleted.
>
> - ide-disk/ide-floppy do the test&call inside the loop rather than after,
> so possibly the call should be moved into the loop, and augmented
> to be "if (drive && drive->proc) ide_remove_proc_entries(...)".
Yes... here is a patch which moves the ide_remove_proc_entries inside the
detection loop. Without ide_remove_proc_entries inside the loop we would
also not unregister more than one device /proc entries, too.
Please test it, works for me.
--- linux-bk/drivers/ide/ide-tape.c 2002-12-19 18:05:07.000000000 -0200
+++ linux-2.4.21/drivers/ide/ide-tape.c 2002-12-19 17:59:39.000000000 -0200
@@ -6597,14 +6597,16 @@
for (minor = 0; minor < MAX_HWIFS * MAX_DRIVES; minor++) {
drive = idetape_chrdevs[minor].drive;
- if (drive != NULL && idetape_cleanup(drive))
- printk(KERN_ERR "ide-tape: %s: cleanup_module() "
- "called while still busy\n", drive->name);
- }
+ if (drive) {
+ if (idetape_cleanup(drive))
+ printk(KERN_ERR "ide-tape: %s: cleanup_module() "
+ "called while still busy\n", drive->name);
#ifdef CONFIG_PROC_FS
- if (drive->proc)
- ide_remove_proc_entries(drive->proc, idetape_proc);
+ if (drive->proc)
+ ide_remove_proc_entries(drive->proc, idetape_proc);
#endif
+ }
+ }
ide_unregister_module(&idetape_module);
}
-
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/
This archive was generated by hypermail 2b29 : Mon Dec 23 2002 - 22:00:25 EST