[Nouveau] [PATCH] drm/nouveau/kms: Implement KDB debug hooks for nouveau KMS.
maximlevitsky at gmail.com
Wed Sep 1 02:56:42 PDT 2010
On Thu, 2010-08-19 at 13:55 -0400, Chris Ball wrote:
> Here's a patch to add support for KMS debugging to Nouveau, along the
> style of the previous patches for Intel¹ and Radeon². I'm only able
> to test on nv50 here, so a test on nv04 would be much appreciated,
> and I've published instructions on how to test here³. Thanks!
> - Chris.
I just tried that patch, but unfortunately nether with nor without it
kdb seems not to work.
It could be id10t error from my side, but I did test the kdb in the past
with few KMS patches, and it seemed to work.
Now I can't even get its prompt on the console.
This is what I do:
echo kbd | sudo tee /sys/module/kgdboc/parameters/kgdboc
(also tried booting with kgdboc=kbd)
Both seems to start kdb, because
maxim at maxim-laptop:~$ cat /sys/module/kgdboc/parameters/kgdboc
maxim at maxim-laptop:~$ dmesg | grep kgdb
[ 0.000000] Command line: BOOT_IMAGE=/boot/vmlinuz-2.6.36-rc3+ root=UUID=52341b68-74f3-4c96-aaf8-7586a06c4b4e ro splash video=nouveau nmi_watchdog=lapic kgdboc=kbd
[ 0.000000] Kernel command line: BOOT_IMAGE=/boot/vmlinuz-2.6.36-rc3+ root=UUID=52341b68-74f3-4c96-aaf8-7586a06c4b4e ro splash video=nouveau nmi_watchdog=lapic kgdboc=kbd
[ 2.671914] kgdb: Registered I/O driver kgdboc.
Now when I first switch to console and then press Alt+SysRQ+G, I just get SYSRQ: DEBUG, and system hangs.
It could be printk level, but that should be ok, no?
maxim at maxim-laptop:~$ cat /proc/sys/kernel/printk
7 4 1 7
Also if I remember correct inputting 'g' then ENTER should resume the system, but it doesn't.
So I think kdb doesn't work at all here
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