Comment 8 for bug 529008

If you're chroot'ing anyway, then you should have privileged access. You could probably do this entirely in userspace, without even specially intercepting the syscalls. When you set up the chroot, just get a copy of how you want cpuinfo to look, and bind mount it on top of the existing cpuinfo file:

root@nimitz:~# egrep cache.size\|^processor /proc/cpuinfo
processor : 0
cache size : 4096 KB
processor : 1
cache size : 4096 KB
root@nimitz:~# cat /proc/cpuinfo | perl -pe 's/4096 KB/8192 KB/g' > cpuinfo.lie
root@nimitz:~# mount --bind cpuinfo.lie /proc/cpuinfo
root@nimitz:~# egrep cache.size\|^processor /proc/cpuinfo
processor : 0
cache size : 8192 KB
processor : 1
cache size : 8192 KB

Would that work?