Bug 46391

Summary:	occassinal kernel panics on boot
Product:	v4l-dvb	Reporter:	Elmar Stellnberger (estellnb)
Component:	v4l-other	Assignee:	v4l-other (v4l-dvb_v4l-other)
Status:	RESOLVED CODE_FIX
Severity:	normal	CC:	alan, luis.henriques
Priority:	P1
Hardware:	All
OS:	Linux
Kernel Version:	3.4.6-2.10-desktop	Subsystem:
Regression:	No	Bisected commit-id:
Attachments:	better compressed screenshot Fix ISR registration Fix ISR registration V2

Description Elmar Stellnberger 2012-08-24 09:22:03 UTC

Since the 3.x kernel (afaicr) the kernel panics occassionally on boot. No trace is left in messages(/var/log/dmesg). The debug output says that there is a NULL pointer dereferenciation when starting the Plymouth graphical boot screen. Now here comes a screen shot:

Comment 1 Elmar Stellnberger 2012-08-24 09:26:31 UTC

Interesting, since I have booted 3.4.6-1.1-desktop with nomodeset (All the KMS related stuff is still bleeding edge; at me KMS does not work at all at the moment (regression): https://bugzilla.novell.com/show_bug.cgi?id=776569).

Comment 2 Elmar Stellnberger 2012-08-24 10:09:41 UTC

uploaded image: www.elstel.com/uploads/kernel-oops/kernel_panic_20120824_100717.jpg, www.elstel.org/uploads/kernel-oops/kernel_panic_20120824_100717.jpg (please try next day; not accessible at the moment.)

Comment 3 Alan 2012-08-24 12:35:13 UTC

Please attach the screenshot to the bug so it doesn't get lost

Comment 4 Elmar Stellnberger 2012-08-25 09:56:57 UTC

Created attachment 78471 [details]
better compressed screenshot

Comment 5 Alan 2012-08-25 11:36:44 UTC

Thanks - stupid bug in the ite remote control driver, enabling interrupts before registering the device. Which as you say would give panics some of he time but not others.

Commit 9ef449c6b31bb6a8e6dedc24de475a3b8c79be20 doesn't move it far enough

Comment 6 Luis Henriques 2012-08-25 14:50:23 UTC

Created attachment 78481 [details]
Fix ISR registration

The attached patch has been compile-tested only, but it should do the trick.  As Alan pointed out, commit 9ef449c6b31bb6a8e6dedc24de475a3b8c79be20 didn't moved the ISR registration far enough.

Please let me know if this solves the problem.  I'll be sending this patch for review to lkml as well.

Comment 7 Luis Henriques 2012-08-25 15:14:05 UTC

Created attachment 78491 [details]
Fix ISR registration V2

Ugh!  Please ignore the previous patch, I attached the wrong version.  Previous patch was the untested one (it didn't compile)

Comment 8 Elmar Stellnberger 2013-10-16 19:59:53 UTC

seems resolved for newer kernels.