Re: PATCH Multithreaded core dump support for the 2.5.14 (and 15) kernel.

Pavel Machek
2002-05-15T20:12:50Z

Hi!

> To respond to your specific question, if a thread happens to be in
> kernel mode when some other thread is dumping core (capturing
> register state of other threads, to be more accurate) then
> we would capture the _user mode_ register of that thread from the
> bottom of it's kernel stack. GDB will show back trace untill the
> thread entered kernel (int 0x80), eip will be pointing to the
> instruction after the system call (return address).

Okay, what about:

Thread 1 is in kernel and holds lock A. You need lock A to dump state.
When you move 1 to phantom runqueue, you loose ability to get A and
deadlock.

What prevents that?
Pavel
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