[User-mode-linux-devel] Re: 2.3.51 panic - probable answer

[Jeff D. <jd...@ka...>]

> One more note; the same Kernel panic showed up when I was slowly
> filling up 24M of uml memory with executing bash over and over again.
> It seems that the hard drive space shrunk (perhaps as the memory used
> by uml grew?), and it seemed as if UML panic'ed right about the time,
> ahem, I ran out of disk space.

What I think is going on is that the hosting kernel only allocates memory (and 
disk space, since the memory is housed in an mmaped file) as the uml touches 
it.  When a disk or memory allocation fails, the uml suddenly finds that 
memory that it thought it had doesn't exist any more.

I've thought about this a bit more, and I think I'm going to consider it as 
equivalent to bad hardware, like a native kernel discovering that it has a 
bank of bad memory.  The native kernel will panic, and the lkml crowd will 
tell you to go away and replace your memory.

I'll see if I can come up with some better diagnostics, though.

				Jeff