[arch-general] weird stuff: segfault in libc and other things

[solsTiCe d'Hiver]

hi.
I switched to [testing] to get gnome 3.
I found that it was a pretty bad timing because I saw that pacman
updated the kernel to 2.6.38 too, and the glibc, and nvidia drivers !
and gnome 3
all in one go. Oh my..;

with gnome 3, I got the gnome-shell segfaulting quite often when I hit
the left top corner. or bottom right corner. 
got log like
Apr  8 19:02:34 soho kernel: gnome-shell[17340]: segfault at 938 ip
b52aa518 sp bfcef0a0 error 4 in libnvidia-glcore.so.270.30[b4423000
+16b3000]
in /var/log/messages.log

and just during the last 30 minutes, all the pc gone "crazy":
chromium stopped to respond. conky stopped to be refreshed. starting a
new shell in a terminal worked but a rm on a file get stuck for no
reason. I switched to a console and log in as root and never got a
prompt. I had to hard reset (I lost no files: the journal has ben
replayed fine)

So I got call trace of chromium crashing in /var/log/messages.log but
other soft too.
This is a snippet of my /var/log/messages.log
http://paste.pocoo.org/show/368742/

Is it a badblock on my /home (reiserfs) partition that produce that
behavior ?
I have done a reiserfsck and a badblock check on the /home partition and
it found nothing.

is it the kernel ? the libc ? 
I saw a convert process that segfaulted in libc ??