amd64/171355: FreeBSD 9.1rc1 (and 10-HEAD) not booting on HP Pavilion g6 2147sl

[Alexander Motin]

The following reply was made to PR amd64/171355; it has been noted by GNATS.

From: Alexander Motin <mav at FreeBSD.org>
To: Stefano Marinelli <stefano at dragas.it>
Cc: attilio at freebsd.org, bug-followup at FreeBSD.org
Subject: Re: amd64/171355: FreeBSD 9.1rc1 (and 10-HEAD) not booting on HP
 Pavilion g6 2147sl
Date: Sat, 08 Sep 2012 19:04:56 +0300

 On 08.09.2012 16:38, Stefano Marinelli wrote:
 >
 >> Could you try to enable CAM debugging by setting kern.cam.dflags=0xff loader tunable either from loader prompt or /boot/loader.conf? It should tell us on what stage of device detection hang happens.
 >
 >
 > Tried that. I can't dmesg, but here's a picture of the screen grabbed just after the hang: http://www.dragas.org/~draga/IMG_20120908_153219.jpg
 
 Thank you.
 
 Unluckily it doesn't show much. I see two things there:
 1) probe of the ATAPI device on second AHCI channel that completed 
 perfectly without any visible problem;
 2) probe start for some device on ctl2cam0 virtual bus that didn't 
 completed there, but it is unclear whether it is related to the problem 
 or just was running in unlucky time. I have no experience to tell what 
 behavior to expect from it.
 
 We should somehow try to find out what happened with disk on first AHCI 
 channel. Unluckily it is impossible to specify single bus for debugging 
 during boot time. So unless your camera can do high-speed series of 
 shots to grab previous screens all we can do is to reduce log details to 
 make them fit the screen. Please try to set kern.cam.dflags separately 
 to 0x40, 0x08 and 0x01, and send me the outputs.
 
 -- 
 Alexander Motin