i386/84563: Panics occur when PAE enabled and >3.5GB memory used

[Jimmy Myrick]

The following reply was made to PR i386/84563; it has been noted by GNATS.

From: Jimmy Myrick <jmyrick at tiger1.tiger.org>
To: <bug-followup at FreeBSD.org>, <dpk at dpk.net>
Cc:  
Subject: Re: i386/84563: Panics occur when PAE enabled and >3.5GB memory used
Date: Thu, 13 Oct 2005 08:11:50 -0500 (CDT)

 This diff also worked for me against 5.4-RELEASE-p8.
 
 The machine is a Dell PowerEdge 2800 that has the same problem.  When
 using a PAE enabled kernel it crashes under heavy loads (buildworld for
 example).  A non PAE enabled kernel works fine, but only addresses around
 3.5 GB of RAM.  The PAE enabled kernel addresses all 4 GB of memory.
 
 After applying the diff, the system works fine with all 4 GB of memory
 available.  Has not crashed under heavy load yet.
 
 Info on what was changed at line 1859 in
 /usr/src/sys/i386/i386/pmap.c:
 
 -					m = PHYS_TO_VM_PAGE(pbits);
 +					m = PHYS_TO_VM_PAGE(*pte);
 
 Jimmy Myrick