npviewer segfaults lock up X

[Bram Mertens]

Hi,

I'm using nspluginwrapper-1.3.0-2 on Fedora 10.

On several occasions (usually after using "switch user") X has
completely locked up (monitor often saying something like "no
signal").

>From dmesg output and the messages file I believe npviewer.bin is at
least involved:

$ dmesg|grep npvi
npviewer.bin[26603]: segfault at 13 ip 0000000001459fb7 sp
00000000ff898ea4 error 4 in libflashplayer.so[d80000+990000]
npviewer.bin[19605]: segfault at ff99cd48 ip 00000000ff99cd48 sp
00000000ffc0a58c error 14
npviewer.bin[23408]: segfault at ff99cd48 ip 00000000ff99cd48 sp
00000000ffba206c error 14
npviewer.bin[17673]: segfault at 3c ip 0000000000fc90da sp
00000000ffc29390 error 4 in libflashplayer.so[d80000+990000]

$ sudo grep npvi /var/log/messages-20091101
Oct 28 19:50:20 localhost kernel: npviewer.bin[19605]: segfault at
ff99cd48 ip 00000000ff99cd48 sp 00000000ffc0a58c error 14
Oct 28 23:17:57 localhost kernel: npviewer.bin[23408]: segfault at
ff99cd48 ip 00000000ff99cd48 sp 00000000ffba206c error 14
Oct 31 18:49:20 localhost kernel: npviewer.bin[17673]: segfault at 3c
ip 0000000000fc90da sp 00000000ffc29390 error 4 in
libflashplayer.so[d80000+990000]

I don't know if it is npviewer.bin or the flash player.
It is very much possible that when this occured a firefox instance was
running with an open tab containing a page using flash.

Is this a known issue?  How can I debug this further?

Kind regards

Bram