kern/127391: [ata] Intel 6300ESB SATA150 cannot find disk and boot under 6.3 [regression]

[Corey Smith]

The following reply was made to PR kern/127391; it has been noted by GNATS.

From: "Corey Smith" <corsmith at gmail.com>
To: "John Baldwin" <jhb at freebsd.org>
Cc: bug-followup at freebsd.org, satz at iranger.com
Subject: Re: kern/127391: [ata] Intel 6300ESB SATA150 cannot find disk and boot under 6.3 [regression]
Date: Wed, 12 Nov 2008 12:55:59 -0500

 On Wed, Nov 12, 2008 at 11:10 AM, John Baldwin <jhb at freebsd.org> wrote:
 > So what the change does is merge a change from HEAD to change how DELAY()
 > works.  Instead going out to the RTC (expensive) it sits in a spin loop
 > polling the TSC.  Can you narrow down a specific DELAY() call in ATA that has
 > a problem?  Also, are you using 'device cpufreq' at all?
 >
 > --
 > John Baldwin
 >
 
 I can't say I understand why this fixes the problem :)  I just know
 that the patch stops the issue from occurring.
 
 2008-11-10's RELENG_6 + this patch with the GENERIC kernel config
 works.  GENERIC doesn't have 'device cpufreq' in it.
 
 If you can come up with a testing protocol I would be willing to give
 it a go...  perhaps I could make a copy of DELAY() called DELAY2()
 with DELAY() being the unpatched implementation and DELAY2() being the
 patched version.  Then I could try test builds changing a single
 DELAY() to DELAY2() in between each build.  Which ever one breaks is
 probably the culprit.  There are 43 DELAY() calls in sys/dev/ata/ so
 it make take a while to figure out.
 
 Does that sound like a reasonable testing strategy?
 
 -Corey Smith