Arch Linux

HashBox

Member

Registered: 2009-01-22

Posts: 271

Mysterious (somewhat reproducable) freeze after boot

Hey guys I'm wondering if anyone can shed any light on a small problem I faced today, sorry about the novel length story..

My PC had been running stable for about a week, and then I installed VirtualBox to do some VM'ing and it warned that I had SVM disabled in my BIOS. This isn't a problem though, I rebooted, enabled SVM and then continued to boot up as normal.

About half a minute after reaching the desktop and opening a terminal, I got a lockup (no mouse movement, switching to a virtual console wouldn't work, appeared to be a hard lockup, but no blinkenlights indicating a panic). Of course I figured that SVM had caused some unstability, so I shut down and disabled it, and booted up again. But alas, the same freeze occurred..

Now I've had problems with my wireless dongle causing lockups in the past, so I spent the next few minutes trying to blacklist different modules while booting, and leaving the wireless dongle unplugged. I blacklisted the VirtualBox modules to no effect, as well as the wireless, all still caused the freeze. I probably tried about 5 - 6 times, and ended up just leaving SVM enabled. As far as I can remember no kernel or general driver updates had taken place before the reboot.

So to narrow it down I then booted into single-user mode, logged in as root, and walked through the multi-user boot process by hand. I loaded the sysctl.conf values, and followed the Arch wiki page on the boot process, which essentially shows that rc.multi just loads the daemons in the daemons array one by one. So I did that, and after each one I waited a while to see if the system would lockup, and it didn't. When I got the end of that, I switched over to the inittab which launches X on my machine. Ran the exact same command to do that (while in a root shell), and X came up.

Then I opened a terminal and entered a couple of commands. This is where it should've frozen up by now, but it didn't. So now I'm currently in "single-user" mode with my regular desktop, services and applications running, and I can't for the life of me figure out why the freeze occurred and I'm mostly wondering if I've missed anything from the multi-user boot sequence

For what it's worth, I considered an unstable CPU, but I'm currently running a VM successfully and AMD-V is working fine now, with 4 cores.. it doesn't seem *random* enough to be general stability problems..

Unfortunately the biggest thing I didn't check was whether or not I was able to SSH into my desktop when the "freeze" occurred, which would've helped me debug an Xorg/Nouveau problem, but hey.

So yeah just wondering if anyone has come across anything similar or could give me some pointers where to investigate the next time I decide to reboot..

Thanks for listening!

ratcheer

Member

Registered: 2011-10-09

Posts: 913

Re: Mysterious (somewhat reproducable) freeze after boot

I had similar freezing last week. It turned out that Arch was leaving my external USB disk drive in a bumfuzzled state when shutting down or restarting.

I had a temporary workaround of disconnecting the USB drive from its power connection for a few seconds, then plugging it back in. But it soon dawned on me that umount'ing the USB drive before shutting down Arch would be cleaner and easier. So far, this has worked every time.

I am not saying that I think this is your problem, but it might be worth looking into.

Tim

HashBox

Member

Registered: 2009-01-22

Posts: 271

Re: Mysterious (somewhat reproducable) freeze after boot

That's quite an interesting one too ratcheer, unfortunately I don't have any USB drives plugged in but that's worth keeping in mind