kern/122318 (CMake core dumping, chroot exiting)

[Sean C. Farley]

On Sat, 26 Jul 2008, Alexander Leidinger wrote:

> Quoting "Sean C. Farley" <scf at FreeBSD.org> (Fri, 25 Jul 2008 15:36:52
> -0500 (CDT)):
>> On Fri, 25 Jul 2008, Chagin Dmitry wrote:
>
>>> uname must work on all supported linuxulators
>>
>> I agree, and it does work until I start playing with the Linux
>> version.
>
> Don't play with the linux version while linux programs are running.
> Changing the version from 2.4.x to 2.6.x and vice versa while a
> program is running is not supported at all and known to cause havoc.
> Roman, do we have the possibility to make an easy check in the sysctl
> handler if a linux program is still running and return an error from
> the handler?  Did I forgot something which makes it impossible to
> switch when a program was run under 2.6 and stopped?

I understand.  This is the first thing I surmised it was since I had
originally changed the versions while a Linux application was running.

> Sean, can you rule out the possibility that a program was still
> running under another version when you've seen the problems with
> uname?

Actually, I was having trouble (at #3 and #9) after:
1. Stopping all Linux applications.
2. Changing the Linux version from 2.6.16 (set at boot in
    /etc/sysctl.conf) to 2.4.2.
3. Running an application.
4. Unmounting linprocfs and linsysfs mount points.
5. Unloading  linux, linprocfs and linsysfs modules.
6. Loading  linux, linprocfs and linsysfs modules.
7. Mounting linprocfs and linsysfs mount points.
8. Setting Linux version to 2.6.16.
9. Running an application.

I do not see how the failures could continue at #9.  How could it carry
the state even after unloading all of the Linux modules?

Sean
-- 
scf at FreeBSD.org