rpms/kexec-tools/devel kexec-kdump-howto.txt, 1.2, 1.3 kexec-tools.spec, 1.117, 1.118

[Neil Horman (nhorman)]

Author: nhorman

Update of /cvs/extras/rpms/kexec-tools/devel
In directory cvs-int.fedora.redhat.com:/tmp/cvs-serv10473

Modified Files:
	kexec-kdump-howto.txt kexec-tools.spec 
Log Message:
Resolves: 456572


Index: kexec-kdump-howto.txt
===================================================================
RCS file: /cvs/extras/rpms/kexec-tools/devel/kexec-kdump-howto.txt,v
retrieving revision 1.2
retrieving revision 1.3
diff -u -r1.2 -r1.3
--- kexec-kdump-howto.txt	5 Jun 2008 15:18:53 -0000	1.2
+++ kexec-kdump-howto.txt	28 Jul 2008 11:26:50 -0000	1.3
@@ -470,30 +470,24 @@
 and when the system reboots, video should be restored to normal.
 
 
-Notes on RHEL5 configuration:
-
-The RHEL5 kexec-utils package contains two extra configuration files:
-
-/etc/sysconfig/kdump
-	This file allows you to specify an alternate kernel to boot in the
-event of a panic (other than the kernel running at the moment), and allows you
-to override or append options on the kernel command line.  It also alows you
-to pass extra options to the kexec utility when the kdump service is starting.
-See documentation in the template kdump sysconfig file for exact usage
-
-/etc/kdump.conf
-	This file allows you to configure how kdump will record your core
-file.  Unlike the stock version of kdump, the RHEL5 version of kdump attempts
-to record your vmcore file from the initramfs, so as to still function
-properly in the event that your root file system is corrupted and unmountable.
-This file is interrogated on kdump service start and is used to populate the
-initramfs for the kdump kernel with the appropriate data and utilities to copy
-your core file to the desired location.  See documentation in /etc/kdump.conf
-for available config directives and targets.  Note especially the ifc option.
-kdump will attempt to determine which network interface to use when dumping to
-a remote server, but due to the possibility of interface renaming, or alternate
-module load strategies, the interface name may change in the kdump kernel.
-This option is used to override that guess, so that the appropriate interface
-will be activated in the kdump kernel.
+Notes on resetting video:
 
+Video is a notoriously difficult issue with kexec.  Video cards contain ROM code
+that controls their initial configuration and setup.  This code is nominally
+accessed and executed from the Bios, and otherwise not safely executable. Since
+the purpose of kexec is to reboot the system without re-executing the Bios, it
+is rather difficult if not impossible to reset video cards with kexec.  The
+result is, that if a system crashes while running in a graphical mode (i.e.
+running X), the screen may appear to become 'frozen' while the dump capture is
+taking place.  A serial console will of course reveal that the system is
+operating and capturing a vmcore image, but a casual observer will see the
+system as hung until the dump completes and a true reboot is executed.
 
+There are two possiblilties to work around this issue.  One is by adding
+--reset-vga to the kexec command line options in /etc/sysconfig/kdump.  This
+tells kdump to write some reasonable default values to the video card register
+file, in the hopes of returning it to a text mode such that boot messages are
+visible on the screen.  It does not work with all video cards however.
+Secondly, it may be worth trying to add vga15fb.ko to the extra_modules list in
+/etc/kdump.conf.  This will attempt to use the video card in framebuffer mode,
+which can blank the screen prior to the start of a dump capture.


Index: kexec-tools.spec
===================================================================
RCS file: /cvs/extras/rpms/kexec-tools/devel/kexec-tools.spec,v
retrieving revision 1.117
retrieving revision 1.118
diff -u -r1.117 -r1.118
--- kexec-tools.spec	14 Jul 2008 14:52:37 -0000	1.117
+++ kexec-tools.spec	28 Jul 2008 11:26:50 -0000	1.118
@@ -1,6 +1,6 @@
 Name: kexec-tools
 Version: 1.102pre 
-Release: 13%{?dist}
+Release: 14%{?dist}
 License: GPL
 Group: Applications/System
 Summary: The kexec/kdump userspace component.
@@ -265,6 +265,9 @@
 
 
 %changelog
+* Mon Jul 28 2008 Neil Horman <nhorman at redhat.com> - 1.102pre-14
+- Add video reset section to docs (bz 456572)
+
 * Mon Jul 11 2008 Neil Horman <nhorman at redhat.com> - 1.102pre-13
 - Fix mkdumprd to support dynamic busybox (bz 443878)