Issues with "x86, um: switch to generic fork/vfork/clone" commit

From: Michel Lespinasse
Date: Fri Nov 09 2012 - 23:37:01 EST


Hi,

I'm having an issue booting current linux-next kernels on my test
machines. Userspace crashes when it's supposed to pivot to the rootfs.
With the loglevel=8 kernel parameter, the last messages I see are:

Checking root filesystem in pivot_root init.
[ 6.252717] usb 2-1: link qh256-0001/ffff880853ec9ab8 start 1 [1/0 us]
[ 6.259419] hub 2-1:1.0: state 7 ports 8 chg 0000 evt 0000
[ 6.292302] traps: hotplug[1633] general protection ip:f767c06b
sp:ffbb2d1c error:0 in libc-2.3.6.so[f7652000+126000]

I ran a bisection and it turns out that
e52d03a3775841cc68d0ea9d86f2f09b603c41e6 (x86, um: switch to generic
fork/vfork/clone) is the commit breaking my setup. When reverting
that, I am able to boot linux-next (or mmotm, which is what I was
trying to do in the first place) without issues.

Sorry for not having a more complete root cause at the moment - I'm
lacking some context as to what the change is trying to do.

--
Michel "Walken" Lespinasse
A program is never fully debugged until the last user dies.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/