Comment 34 for bug 241145

I am having the same problem. On Hardy on x86_64, using 2.6.22-14-generic (2.6.24 has problems with suspend on my machine). It only happens when flashplugin-nonfree is installed, but seems to happen randomly, not necessarily when I'm interacting with flash. X just restarts and I get a login page. My Xorg.0.log.old is attached. I didn't have this problem with Gutsy.

Backtrace:
0: /usr/bin/X(xf86SigHandler+0x6a) [0x48402a]
1: /lib/libc.so.6 [0x2b7bda1f7100]
2: /usr/lib/xorg/modules//libxaa.so [0x2b7bdd265c9c]
3: /usr/lib/xorg/modules//libxaa.so [0x2b7bdd265e96]
4: /usr/bin/X [0x527ea2]
5: /usr/bin/X [0x515c3f]
6: /usr/bin/X(Dispatch+0x2ef) [0x44eaaf]
7: /usr/bin/X(main+0x47d) [0x436b9d]
8: /lib/libc.so.6(__libc_start_main+0xf4) [0x2b7bda1e31c4]
9: /usr/bin/X(FontFileCompleteXLFD+0x279) [0x435ed9]