Chase Venters

How does that happen?

Mon, 07 Jul 2008 01:07:54 GMT

One of the oddest things I've seen in a while has just occurred. I tried installing CentOS 5.2 inside kvm. The kernel off the installer CD image will not boot; it reaches a panic due to a NULL pointer dereference in some cpufreq code.

It looks like the offending code is part of an aftermarket patch; perhaps Xen. Looking just at context lines in a diff referred to by one of the bug reports, it appears that the offending code is a hack for Hewlett-Packard systems. The problem is that the function assumes a "dmi_data" exists, containing the DMI... but the DMI is corrupt or unavailable on some systems (notably in this case, kvm).

The bug itself is utterly unsurprising. These things happen. What is very curious is the fact that a bug like this showed up in a major CentOS release. Of course, CentOS is just Red Hat Enterprise Linux without the trademarks, so we see that the issue has also been reported to Red Hat. It's hard to imagine that during the whole QA process for 5.2, no one ever tried running the kernel under kvm or qemu.

Whoops! or, the silly things done by software

Tue, 04 Mar 2008 13:48:11 GMT

I'm currently working on a server that will make use of a piece of software called astmanproxy.

astmanproxy is an Asterisk Manager Protocol proxy application. It addresses a known reliability issue with the Asterisk manager API; namely, the fact that Asterisk has had a history of problems related to handling these connections. Many PBX applications communicate with Asterisk over this protocol, which has resulted in the development of proxies such as astmanproxy to relieve the buggy Asterisk code of the burden of handling individual, short-lived connections.

astmanproxy looks at least functional though I'm not greatly impressed with the code quality. In a hurry to get it up and running, I skimmed the documentation, compiled and installed it, and had a go at editing and trimming the default configuration file. The result was an astmanproxy that would connect to Asterisk but then get rejected as it tried to authenticate.

After a half hour worth of frustration attempting to debug the issue from an Asterisk perspective, including setting new passwords and trying new accounts, scanning debugging output from astmanproxy and finally leaning on tcpdump, I realized the issue: astmanproxy's configuration file parser converts everything to lowercase.

The documentation doesn't say a word about this, of course. Nor does the configuration file. But the consequence is that you just can't use passwords with astmanproxy that contain an uppercase character. I admit surprise at the fact the application is up to 1.21 and this issue has been neither documented nor addressed. Am I the first to notice?

Urge to Punch Reaches Epic Levels

Sun, 24 Feb 2008 16:48:45 GMT

My last post dealt with the frustration I felt in trying to find a garage door remote that wasn't huge and would support more than one version of one single manufacturer's protocol.

I'll make this brief: the "Clicker" I purchased developed a rather annoying problem. It now eats 9V batteries like popcorn. Fresh batteries will be destroyed in a matter of days, which may only include a single use. It appears to drain said batteries while the remote is not in use, and without lighting the activity LED you'd expect to see if it were a mechanical problem along the lines of a stuck button.

In the end, I had to cast that crap aside and settle for an official single-button Chamberlain remote made for the specific protocol of the door. It's certainly bigger than it needs to be, but it is smaller than the Clicker, and so far, it gets the job done.

Urge to Punch Rising...

Sat, 15 Sep 2007 16:46:42 GMT

People often find technology to be incredibly frustrating. For many, it's a matter of the difficulty in using technology, or the ways in which it misbehaves... but for me, the frustration often bubbles up when I come across technology that could and indeed should have been better.

Presently, my primary frustration is with the garage door opener market. There have been many technologies and protocols used by wireless garage door openers over the last decades. One of the consequences of this is vast incompatibility.

This bit me in the ass once when I cluelessly purchased a Genie-brand remote to open a Chamberlain Security+ door. That was actually a while ago, but I've now got a useless Genie remote. I ended up with the proper Chamberlain Security+ remote. It's a bulky unit, which is frustrating when space in my Miata is at a premium.

I moved to a new apartment recently. The garage door opener in this apartment is a LiftMaster, also bearing the Chamberlain name. Pleased that I wouldn't need to buy a new controller, I attempted to link my remote to the door with no success. Apparently, the "billion code" technology in this unit is obsolete.

Frustrated, I tried Home Depot, hoping to find a decent controller that would open both the new garage door and the old one. My purchasing choices were limited between mini-remotes (in a form factor I would much prefer) that wouldn't open the apartment garage door, equally bulky units that would only open the apartment garage door and not the old one, or an absolutely large "Clicker" with two buttons that was allegedly compatible with both.

I had the Clicker in my hand, about to give in and fork over the $20, but I was too disgusted with the size of the unit to make the purchase. I reasoned that I must be able to find a better unit on the Internet.

Unfortunately, it looks like I'm not in luck -- not in the slightest. Just shopping for an opener is a challenge -- the brand names, the color-coded learning buttons, frequencies, and manufacturing years all create a muddled mess. And just in case the shopping experience doesn't make you want to vomit, you'll find that nearly all of the devices will.

At this point, I have to step back and catch my breath. It's a fucking garage door opener -- a very simple RF device! Why are they all so bulky? You could probably cram 2... maybe 4 embedded Linux systems in the Clicker. Actually, with some of the "Linux in an ethernet connector" technology, you might be able to get 8 or 10 in there.

It's also gross that the landscape is littered with incompatible devices. I'm particularly surprised that Chamberlain doesn't sell a reasonably-sized opener that will open both their new and old doors. Perhaps what's holding back the market for a sane universal remote is that companies like Chamberlain would rather file disgustingly frivilous lawsuits against competitors making compatible openers than do any kind of real innovation themselves.

At times like this, I wish the landscape could all be blamed on one incompetent engineer or clueless manager - someone I could walk up to, then proceed to punch squarely in the face. But alas; I'm dealing with companies, industry and government. You can't punch a patent law and you can't punch proprietary "intellectual property." All you can do is hope that some day, the industry will behave more like the software industry is beginning to behave, by implementing open standards that benefit customer and the market alike.

Picking Your Battles

Mon, 27 Aug 2007 22:13:14 GMT

Trying to organize your desk and your life can be a real chore sometimes. Lately, I've been going through spurts of undoing the madness I've accumulated in the years passed.

I've been a pack-rat of tangible things, and so I've been throwing away much I feel is now unnecessary (such as old issues of PC Gamer from my years of youth). But no matter how much ends up in the garbage, there is always more work to be done.

Lately I've taken a diversion to cleaning up my PC. This is going to be a much more difficult challenge: data is easier to pack-rat than physical goods, because all the data I have fits into a power-sucking RAID array inside a small tower. But I have identified one area where I can make progress, and so I have.

Over the last few years, I went on a subscription spree. I signed up for the mailing lists of KDE, xorg, the Linux kernel, hal, dbus, Familiar, mod_perl, Apache, Gentoo, and others. I am genuinely interested in what is going on in each of these fronts, but I barely have the time left to read lkml, much less any of the others.

I let messages accumulate from these lists into a set of Maildir folders underneath one of my email accounts. My mailer (KMail) wept visibly trying to keep up with all these messages. Strange glitches were common. Kontact, the organizer application that wraps KMail, consumed on average 25% of my available page frames (2 GB). I mitigated the glitches with a Perl script that would archive the messages of high traffic mailing lists into an archive subfolder, keeping only the most recent 2000 in the main folder, but the memory usage remained.

It took forever to come to the common-sense realization that there was no way on Earth I could personally consume all this information. When I decided to go on an unsubscription spree, I had over 170,000 unread messages. Deleting them brought Kontact's RSS to 5%, and became one more step in my ongoing process of learning to pick my battles.

I've decided to keep my subscription to two lists: lkml, and cryptography@metzdowd.com. I don't really have the time to read either of them right now, but I couldn't let these ones go. :P

Disk Space, Continued

Tue, 24 Jul 2007 13:29:27 GMT

Ugh. This is so depressing:

turbotaz ~ # df --si Filesystem Size Used Avail Use% Mounted on /dev/md/1 628G 589G 7.6G 99% / udev 1.1G 312k 1.1G 1% /dev shm 1.1G 0 1.1G 0% /dev/shm /dev/md/0 104M 11M 88M 12% /boot

Imperfection

Mon, 23 Jul 2007 23:01:25 GMT

Perfectionism is a vice I find myself facing from time to time, and it shows its ugliest head when I'm doing software development.

I consider myself lucky that I don't face perfectionism when I'm hacking a quick and dirty Perl script together (else, I'd be a very dysfunctional admin). As many admins, I have a large ad-hoc collection of Perl scripts doing various jobs for me (such as tweaking domain settings en masse on Joker), and though I tend to start at the very least with use strict;, my scripts still end up being an undocumented mess with dangling code and an arbitrary mixture of spaces and tabs (from when I use Konsole's copy-paste to go from vim on one terminal to another). These scripts require a little love to modify and maintain, but they do their short-term jobs very well.

When it comes to "real" software development, however, I hold myself to a very high standard, and hence it always makes me uncomfortable when I'm relying on someone else's code that might be good but lacking. I'm encountering a nice patch of that now.

Bizarro World

Fri, 15 Jun 2007 08:44:30 GMT

It's simply incredible the opinions some people hold. These are in response to a Jonathan Schwartz blog entry about cooperation with Linux, which I'd be tempted to comment on if I wasn't so distracted by the stupidity of some of the comments. I believe some of these speak for themselves:

Very good response from the CEO of a company Linus accused (to the extent of sounding like FUD) in the mail thread. The Linus mail would made some think he's getting increasingly scared of OpenSolaris. He was a more reasonable guy sometime back. Anyhow, hope the dinner works out well for both of you.

You might not find this one as hilarious as I do until you read what Linus said in full.

I think Linus' comments on Solaris show just how out of touch he is with other operating systems and the reason Linux has plateaued technically as an OS.

Linus' says ZFS is the only thing interesting about Solaris? That's one thing more than Linux has going for it.

Yes, Linux has nothing going for it whatsoever. Microsoft's fear of Linux is actually just an elaborate piece of comedy paid for by its shareholders.

I really get amused when some one mentions that they use Linux because it is free and it is open source. My immediate naïve question to them would be is – so which Linux do you use? The answer 99.99% would be – RedHat or Novell!! They do not realize that they “paid” RedHat or Novell for the distribution. So Johnathan is right RedHat and Novell hurt Sun more than what Linux did to Solaris. So did Sun really learn from RedHat regarding packaging or distributing an operating system? No it did not, it never will.

Honestly, I think Linux has a growth issue and its vast user base has to be nervous about it. Sun’s investment in Solaris might not have any impact on the share holder value for a while, but Linux has a lot of catching up to do.

Catching up? To Solaris?

For the record, I have respect for Solaris. But it amazes me when people in 2007 are still acting like Linux is a fragile newcomer without any desireable aspects or innovation. Talk about living under a rock.

Victims of wishful thinking?

Tue, 15 May 2007 13:08:17 GMT

It seems there is some amount of question as to whether the report about AMD delivering open-source drivers, made by Enterprise Linux Log, is entirely correct.

Wishful thinking? Perhaps. What Henri Richard apparently said was that AMD/ATI would improve relations with the community. Dave Airlie doesn't seem completely convinced:

So a marketing dude said something about open drivers for AMD/ATI gpus and working with the community.

Can people get excited when AMD/ATI actually do something rather than showboat for media headlines?

Like ATI won't let me release my r500 source because I shouldn't have used a utility they gave me under NDA on those cards, now the thing is I done the correct thing and contacted them asking if I could release the code, so far this has just been stonewalled by their Linux driver management and their "legal" department, this isn't the action of a company trying to interact with the community or one that gives a rats arse about community..

I don't know for sure, but Henri Richard's e-mail address might be henri.richard@amd.com. If AMD is indeed interested in improving relations with the community, perhaps we should e-mail them asking for them to clear the release of Dave Airlie's r500 source?

AMD to Free Graphics Drivers

Sun, 13 May 2007 10:39:52 GMT

I just saw this myself: AMD is committing to freeing its graphics drivers.

AMD will soon deliver open graphics drivers, said Henri Richard just a few minutes ago, and the audience at the opening keynote of the Red Hat Summit broke into applause and cheers. Richard, AMD's executive vice president of sales and marketing, promised: "I'm here to commit to you that it's going to get done." He also promised that AMD is "going to be very proactive in changing way we interface with the Linux community."

If they make good on this promise, it will be fantastic for GNU/Linux users. Currently, ATI graphics support is very lackluster on the platform. NVIDIA offers a proprietary driver that mostly works, but their closed development has injured the community's ability to advance the state of X.org, and challenged the ability for GNU/Linux distributions to "just work".

I commit that if AMD makes good on this announcement and produces a reasonably working free driver for Linux and X.org, and NVIDIA has not matched their offering at the time I need to upgrade, I will definitely purchase an AMD/ATI card.