Re: kern/49398 (i386-current GENERIC (i915drmkms) boot hangs if monitor powered off)

["John D. Baker" <jdbaker%mylinuxisp.com@localhost>]

The following reply was made to PR kern/49398; it has been noted by GNATS.

From: "John D. Baker" <jdbaker%mylinuxisp.com@localhost>
To: gnats-bugs%NetBSD.org@localhost
Cc: riastradh%NetBSD.org@localhost
Subject: Re: kern/49398 (i386-current GENERIC (i915drmkms) boot hangs if
 monitor powered off)
Date: Thu, 14 May 2015 23:39:20 -0500 (CDT)

 On Thu, 14 May 2015, riastradh%NetBSD.org@localhost wrote:
 
 > State-Changed-Why:
 > Via the serial console, can you get a stack trace from ddb?
 
 When last I tried, I could not.  The machine was completely hung and
 required power-cycle to regain control.
 
 > If not, we can try printf debugging.  I'd start by adding printfs
 > around all the calls to drm_add_edid_modes in i915, and throughout
 > drmfb_attach.  That should be enough to get started, but I can supply
 > a patch if you'd like.
 
 I am away from the machine until early June and can try then.
 
 > Also: does this happen on any machine other than your i845?
 
 Of the only other machines I have with intel graphics, one doesn't power
 up due to bad capacitors.  The other uses an i82945G/P, but it only
 ever boots a kernel with DRM/KMS disabled entirely and is generally not
 available for testing (it's my file server).  As such, it reboots just
 fine even when the monitor is off.
 
 I may have access to other intel-graphics-equipped machines I can poke
 at, but it will be early June before I can try.
 
 So far, the problem does not occur on radeon-equipped machines.
 
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