For a current Fedora "rawhide" system, X crashes on start-up complaining about an aperture range error when the savage driver is used. The distribution related bug report is:

  https://bugzilla.redhat.com/show_bug.cgi?id=426994

The tail of Xorg.0.log with debugging information is:
-------------------------------------------------------------------------------
(EE) SAVAGE(0): Internal error: cound not map aperture range (7, Argument list too long).

Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0xb7fa2710 (LWP 3763)]
0x0030bd9e in SavageDisableMMIO (pScrn=0x9170860) at savage_driver.c:4348
4348		VGAOUT8(vgaCRIndex, 0x40);
(gdb) Undefined command: "module".  Try "help".
(gdb) #0  0x0030bd9e in SavageDisableMMIO (pScrn=0x9170860) at savage_driver.c:4348
#1  0x0030d51a in SavageUnmapMem (pScrn=0x9170860, All=1)
    at savage_driver.c:3229
#2  0x0030d65f in SavageFreeRec (pScrn=0x9170860) at savage_driver.c:822
#3  0x0030ed7e in SavagePreInit (pScrn=0x83d4, flags=<value optimized out>)
    at savage_driver.c:2314
#4  0x080a1fd9 in InitOutput (pScreenInfo=0x82180a0, argc=4, argv=0xbfb43414)
    at xf86Init.c:765
#5  0x0806ccd6 in main (argc=4, argv=0xbfb43414, envp=0xbfb43428) at main.c:369
(gdb) Continuing.

Backtrace:
0: /usr/bin/Xorg(xf86SigHandler+0x79) [0x80c6399]
1: [0x110420]
2: /usr/lib/xorg/modules/drivers//savage_drv.so [0x30bd9e]
3: /usr/lib/xorg/modules/drivers//savage_drv.so [0x30d51a]
4: /usr/lib/xorg/modules/drivers//savage_drv.so [0x30d65f]
5: /usr/lib/xorg/modules/drivers//savage_drv.so [0x30ed7e]
6: /usr/bin/Xorg(InitOutput+0x979) [0x80a1fd9]
7: /usr/bin/Xorg(main+0x286) [0x806ccd6]
8: /lib/libc.so.6(__libc_start_main+0xe0) [0x42c4a0]
9: /usr/bin/Xorg(FontFileCompleteXLFD+0x24d) [0x806c1d1]

Fatal server error:
Caught signal 11.  Server aborting
-------------------------------------------------------------------------------
This used to work up to Xorg 7.3. The crash occurs even for the latest git version.