# Laptop lid close = indefinite kernel lock?

## knifeyspoony

Hi,

Just before bedtime last night, I set my laptop to emerge four packages and && poweroff and closed the lid. I fell asleep quickly. In the morning I awoke from a dream that seemed epic-length, though was probably only a minute long in real time. And when I awoke, I found that I had turned deactivated my alarm clock in my sleep. Almost 8 AM.

My laptop was still on, so I figured the emerge failed for some reason. When I unlocked it, it occurred to me that my circadian rhythms might finally be in sympathetic harmony with this machine I spend so much time with. The system clock was still at just after 11 PM local, and VLC (2 of 4) was still compiling!

The system must have locked at about the time I closed the lid, and resumed when I opened it. For this morning, I saw the compiler messages pass with great speed, and VLC and the remaining two packages finished quickly.

Syslog has this from 11:01 PM

```
BUG: soft lockup - CPU#1 stuck for 99s! [events/1:10]
```

followed by a list of modules. I haven't found anything else interesting in logs.

For now I've changed my KDE 4.3.3 power profiles to "Do Nothing" when I close my lid, from the seemingly redundant "Turn Off Monitor". I haven't tested the change yet, although I don't know if the behavior could be reliably reproduced, either.

I'm very curious what happened. Does anyone know? Is there some extra logging I could turn on?

```
Linux smuckers 2.6.31-gentoo-r6 #1 SMP Mon Jan 11 06:15:30 EST 2010 x86_64 AMD Athlon(tm) 64 X2 Dual-Core Processor TK-55 AuthenticAMD GNU/Linux
```

-ks

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## Hu

Extra logging may be available, but we need to localize the problem before we can tell which logging features would be useful.  Could you describe the laptop specifications, such as number of CPUs, type of video card, approximate age, etc.?  I see the CPUs are generally described in the uname, but I am reluctant to guess too much from a marketing name.  What is the output of emerge --info ; lsmod?  The full output from that BUG statement may also be helpful.  It should contain a callstack that will tell us where the kernel got stuck.  Even so, it is strange that it reported being stuck for 99s, but was in fact stuck for many hours.

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## knifeyspoony

Thanks, Hu:

This is a Dell Vostro 1000. It is a little over two years old. It has a Radeon Xpress 200 video card, an older type which the closed-source ATI driver no longer supports. It has one dual-core CPU.

emerge --info: http://pastebin.ca/1760988

message log: http://pastebin.ca/1760990  --lockup message plus a list of linked-in modules

current lsmod: http://pastebin.ca/1760986

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## knifeyspoony

As I mentioned above, I disabled all power management features in KDE System Settings. But I had another ~6 hour lock today. Again, it was while compiling; and again, work resumed instantly when I opened my laptop.

Should I look at more logs? Report a bug?

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## Hu

At this point, you need more help than I can provide.  Reporting a bug may be your best course of action.  If possible, try to reproduce the issue with a vanilla kernel, then report the issue directly to the kernel.org developers if the vanilla kernel is affected.

It would be interesting to know if the system will always do this if the CPU is busy when the lid is closed.  Could you try running a forever loop, such as while :; do :;done, for each core, and then close the lid?

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