[uml-devel] [PATCH] Converting mconsole to SOCK_STREAM

[Erik W. <be...@pd...>]

A few months ago I posted a patch to add a shutdown notification to the
mconsole, and was told that the better solution was to convert the
mconsole socket over to a STREAM socket, which allows a management app
to detect the shutdown of a machine via the closed socket.  This avoids
potential races between the shutdown notification packet and the final
exit() of the kernel.

I've attached the patches to both the kernel and to uml_mconsole.c. 
They've been running on our machines for over a month, but I'm seeing
spurious panics and even complete kernel death every once in a while,
and I suspect that my patch is not fully correct.

I'm not sure I fully understand the mechanics of constantly adding and
removing filedescriptors to the soft-IRQ without things breaking.  In
fact, every time I reconnect to the mconsole, I get:

Registering fd 17 twice
Irqs : 9, 9
Ids : 0x11, 0x11

So I know something isn't quite right.  I'll spend some more time trying
to figure it out, but I'd love it if someone else has some good ideas as
to what I might be doing wrong.

I've got several other patches of lesser impact that I'll post shortly,
none of which appear to have anything significant in the way of bugs. 
All are closely related to management of multiple instances of UML.

TTYL,
   Omega
   aka Erik Walthinsen
   om...@pd...

P.S. in case you haven't figured it out from the name, pdxcolo.net is
doing UML hosting [and soon other stuff].  We've got plenty of beta-test
slots left if anyone wants to give it a try.  Email us at
be...@pd... if you want to give it a try.