nVidia fails on Gentoo

I’ve compiled new kernel for Gentoo Linux running on my wife’s computer and X server failed to start. In log I found:

(EE) NVIDIA(0): Failed to obtain a shared memory identifier.

It took me a couple of hours to bring it back to life. So if you experience similar issue here’s the quick answer:

Probably System V IPC is not enabled in your kernel configuration. Enable it running make menuconfig and checking

General setup —> [*] System V IPC

or just set


in /usr/src/linux/.config file manually.

Recompile both kernel and nVidia driver and reboot. It worked for me.