On Sun, 5 Aug 2018, co...@sdf.org wrote:
Hi folks,
we're working on a drmkms update.
I'm testing it on a Dell XPS 9550. It's a laptop with a Skylake CPU.
It has a power button. The power button powers off, not reboot.
This means the dmesg buffer gets wiped.
No serial console as far as I know.
Now it reaches a point where the screen changes, but my DDB_COMMANDENTER
containing "reboot" won't do the expected thing. It's possible it's
hanging. I can't seem to blindly enter ddb.
Any suggestions to make debugging less painful?
Something like arm a watchdog to panic after some time.
I'm gonna experiment with sprinkling panic("XXX"); and see if this works
out.
Can't you tell DDB to 'reboot 0x100' to force a crash dump? Then the
message buffer should be saved in the dump file.
+------------------+--------------------------+----------------------------+
| Paul Goyette | PGP Key fingerprint: | E-mail addresses: |
| (Retired) | FA29 0E3B 35AF E8AE 6651 | paul at whooppee dot com |
| Kernel Developer | 0786 F758 55DE 53BA 7731 | pgoyette at netbsd dot org |
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