BUG: soft lockup - CPU 1 stuck for 11s

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BUG: soft lockup - CPU#1 stuck for 11s! [nameofwhatwasblocked]

...with varying CPU number, length, and process name.

Will be followed by more process details, such as the PID, the modules loaded in, and the execution state of the process (registers and call trace).

Despite the call trace, this message is itself an informational warning, not an error or crash.

That said, it's roughly saying that the scheduler didn't get it to budge towards doing anything at all for a couple billion cycles, and that is probably something you want to understand the cause of. And avoid in the future if you can.

One possible cause is (extremely overcommitted memory leading to) swapping to the point of trashing, basically meaning the CPU has to wait for disk before a scheduled process can properly continue.

It looks like certain buggy drivers (e.g. ndiswrapper stuff) can be reported as the process blocked waiting for that driver.

Specific bits of hardware issues could do the same, broken or interacting in a non-conforming way (noapic sometimes helps, bios update can help)