From Bugzilla Helper: User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.3) Gecko/20041020 Description of problem: Filed against distribution because I can't idenify the offending component. The system keeps freezing hard and has to be hard-reset. This has only been happening in the past two weeks, so it must be related to recent updates. Empirical statistics point a finger at something to do with video. The freezes always occur when attempting to view certain things, never otherwise. Example: opening a certain html file with vi is OK until the moment I scroll down to an <em> section. The very moment I can see the beginning of the black <em> text on the screen, the system freezes and I have to press the reset button. Every time. But then again, it could have to do with the file itself and not with its display. Another freeze comes often - but not always - with opening a default icecast status page in mozilla, although opening the same page in konqueror is just fine. No traces whatsoever in the logs. The machine is an ASUS A7N8X-X with ATI Rage 128 Pro Ultra VGA running 2.6.10-1.741_FC3 or 2.6.9-1.724_FC3 kernel (no difference), KDE and nothing particularly suspicious. Three partitions are encrypted with dm-crypt, but two of them have been so for many months without freezes. And yes, the heat sink is new and clean and the whole system, motherboard, RAM and CPU, is brand new (bug #137804, comment #8). This is the typical elusive bug that won't let itself be easily pinpointed, so I'm willing to give root to redhat staff that's willing to take a go at it. How reproducible: Sometimes
In the week that passed since I reported this, I have had one or two non-vi-related freezes and more than a dozen directly triggered by vi. With certain files it happens every single time, no exceptions. As I found out, the vi help is one of them. I open vi, type ':help', start scrolling down one line at a time. At the fourth line the machine freezes. Normally I use KDE and vi in gnome-terminal. I tried in Gnome and it froze too. I tried turning off syntax highlighting to no avail. I tried in runlevel 3 and whoops, problem gone. I can open the vi help and all the files that cause the freezes without any problems. BTW, all this happens with me logged in as an unprivileged user, not as root.
One thing I hadn't checked is whether the machine could be accessed from the network when the keyboard and mouse are frozen. Now I did and it cannot. It doesn't even answer to ping, so it is really completely frozen.
Since I updated the machine yesterday with, among others, kdegraphics-3.3.1-2.3, things got worse. Much worse. I can hardly open mozilla mail without freezing, I had to press the reset button five times in the last half hour and move to kmail. This is more exhasperating than Windows 95 ever was. Kernel 766, 760 or 741 makes no difference; the system is absolutely useless.
I compiled a vanilla 2.6.10 kernel using /lib/modules/2.6.10-1.766_FC3/build/.config, with the only difference that I added CONFIG_MK7=y. Rebooted, opened mozila mail and froze before I could even enter a password. At least we know now that it's not the redhat kernel patches that cause this. Subsequently I boouted the 766 fedora kernel, downgraded kdelibs to 3.3.1-2.4.FC3 and kdegraphics to 3.3.1-2.3 and restarted X. I was now able to start mozilla mail and use it for more than ten minutes without freezing. That's significant progress compared with an hour ago, and it suggests a possible narrowing down. The timing described in comment #1 coincides with the release of kdelibs-3.3.1-2.6.FC3. My gut feeling is that something userland triggers the freezes, and the kernel then allows them to happen. That would certainly be a kernel bug, but the userland problem is also a bug. Finding the userland bug could help a lot in narrowing down the kernel bug. From here I'll go to downgrading kdelibs to 3.3.1-2.4 and see if it makes any difference. All bright ideas what else to try are welcome.
An update has been released for Fedora Core 3 (kernel-2.6.12-1.1372_FC3) which may contain a fix for your problem. Please update to this new kernel, and report whether or not it fixes your problem. If you have updated to Fedora Core 4 since this bug was opened, and the problem still occurs with the latest updates for that release, please change the version field of this bug to 'fc4'. Thank you.
I won't be able to test this until next month. It's not lack of interest, so please don't close the bug in the meanwhile.
I am finally back at that machine and tested it. With all FC3 updates up to September 21, including the latest kernel, the system kept freezing as before. It also kept freezing after I upgraded it to CentOS 4.1. Replacing the ATI Rage 128 video card with an ATI Radeon 7000 finally solved the problem. There doesn't seem to be anything wrong with the Rage card hardware-wise, so the suspect is the driver and whatever change was made to it around January this year.
Since this bugzilla report was filed, there have been several major updates to the X Window System, which may resolve this issue. Users who have experienced this problem are encouraged to upgrade to the latest version of Fedora Core, which can be obtained from: http://fedora.redhat.com/download If this issue turns out to still be reproduceable in the latest version of Fedora Core, please file a bug report in the X.Org bugzilla located at http://bugs.freedesktop.org in the "xorg" component. Once you've filed your bug report to X.Org, if you paste the new bug URL here, Red Hat will continue to track the issue in the centralized X.Org bug tracker, and will review any bug fixes that become available for consideration in future updates. Setting status to "CURRENTRELEASE".