Can't control backlight; strange segfault

I'm using Arch Linux on my Packard Bell EasyNote TX86 (Intel HD Graphics, Core i5) and I can't control the backlight (it's always on max). xbacklight and writing to /sys/class/backlight does nothing. I tried

xrandr --output LVDS --set BACKLIGHT_CONTROL native

but it segfaults X with

Backtrace:
[   308.398] 0: /usr/bin/X (xorg_backtrace+0x3b) [0x80e685b]
[   308.398] 1: /usr/bin/X (0x8048000+0x64895) [0x80ac895]
[   308.398] 2: (vdso) (__kernel_rt_sigreturn+0x0) [0xb770140c]
[   308.398] 3: /usr/bin/X (0x8048000+0xbe860) [0x8106860]
[   308.398] 4: /usr/bin/X (0x8048000+0x23e57) [0x806be57]
[   308.398] 5: /usr/bin/X (0x8048000+0x1a135) [0x8062135]
[   308.398] 6: /lib/libc.so.6 (__libc_start_main+0xe6) [0xb7442c76]
[   308.398] 7: /usr/bin/X (0x8048000+0x19d11) [0x8061d11]
[   308.398] Segmentation fault at address 0x48
[   308.398] 
Fatal server error:
[   308.398] Caught signal 11 (Segmentation fault). Server aborting

Ubuntu can't control it either, but Windows can. Any ideas? I'd love to use Linux full time but it eats my battery.

Solution 1:

This is no longer a problem, the kernel has supported it for a while.