[Bug 50813] 2.6.15-xx ppc kernel fails to boot on G4

[Mike]

Public bug reported:

1. Upgraded successfully from Breezy to Dapper on Mac G4
2. On reboot, found I had to choose "old" kernel to come back up.  If I instead chose the default "linux" kernel, a white screen was produced, then a blinking light on my monitor with a totally hung machine.  No error messages appeared on the screen, which stayed white.  

Above "old" corresponded to vmlinux-2.6.12-10-powerpc (the last kernel I
had on Breezy).  It is still my working Kernel today.  "linux"
corresponded to vmlinux-2.6.15-23-powerpc.  That kernel is the one that
produced a white screen and died.

A few days or perhaps a week ago, I was encouraged when Dapper released
a new kernel, vmlinux-2.6.15-25-powerpc.  However, that produces the
same results as vmlinux-2.6.15-23-powerpc.

Here are some details about my machine that I hope will help you fix the problem.  Since I run newer kernels under Gentoo and Fedora on G3 and G4 powerpc's, I think it's not a kernel problem per se, but perhaps something with the patches provided specific to debian or ubuntu.  Don't know.  I just hope you can fix it as Ubuntu is one of my favorite distros.
mike at monkey:~$ cat /proc/cpuinfo
processor       : 0
cpu             : 7400, altivec supported
temperature     : 42-44 C (uncalibrated)
clock           : 400MHz
revision        : 2.9 (pvr 000c 0209)
bogomips        : 794.62
machine         : PowerMac3,1
motherboard     : PowerMac3,1 MacRISC Power Macintosh
detected as     : 65 (PowerMac G4 AGP Graphics)
pmac flags      : 00000004
L2 cache        : 1024K unified
memory          : 544MB
pmac-generation : NewWorld

mike at monkey:~$ lspci
0000:00:0b.0 Host bridge: Apple Computer Inc. UniNorth AGP
0001:10:0b.0 Host bridge: Apple Computer Inc. UniNorth PCI
0001:10:0d.0 PCI bridge: Digital Equipment Corporation DECchip 21154 (rev 05)
0001:11:02.0 VGA compatible controller: ATI Technologies Inc RV280 [Radeon 9200] (rev 01)
0001:11:07.0 ff00: Apple Computer Inc. KeyLargo Mac I/O (rev 02)
0001:11:08.0 USB Controller: Apple Computer Inc. KeyLargo USB
0001:11:09.0 USB Controller: Apple Computer Inc. KeyLargo USB
0001:11:0a.0 FireWire (IEEE 1394): Texas Instruments TSB12LV23 IEEE-1394 Controller
0002:21:0b.0 Host bridge: Apple Computer Inc. UniNorth Internal PCI
0002:21:0f.0 Ethernet controller: Apple Computer Inc. UniNorth GMAC (Sun GEM) (rev 01)

mike at monkey:~$ lsusb
Bus 002 Device 002: ID 045e:0040 Microsoft Corp. Wheel Mouse Optical
Bus 002 Device 001: ID 0000:0000
Bus 001 Device 004: ID 0430:0005 Sun Microsystems, Inc. Type 6 Keyboard
Bus 001 Device 001: ID 0000:0000

mike at monkey:~$ cat /proc/meminfo
MemTotal:       546692 kB
MemFree:          3988 kB
Buffers:          3092 kB
Cached:         117584 kB
SwapCached:        556 kB
Active:         448724 kB
Inactive:        51912 kB
HighTotal:           0 kB
HighFree:            0 kB
LowTotal:       546692 kB
LowFree:          3988 kB
SwapTotal:     1562492 kB
SwapFree:      1556640 kB
Dirty:              16 kB
Writeback:           0 kB
Mapped:         438736 kB
Slab:            15600 kB
CommitLimit:   1835836 kB
Committed_AS:  1616548 kB
PageTables:       2656 kB
VmallocTotal:   416320 kB
VmallocUsed:     44616 kB
VmallocChunk:   371396 kB

My current /boot.  Note I had to change the softlinks to point back to
my old working kernel:

mike at monkey:~$ ls -l /boot
total 48605
-rw-r--r-- 1 root root  208302 2006-04-28 15:44 abi-2.6.12-10-powerpc
-rw-r--r-- 1 root root  208261 2005-10-10 16:47 abi-2.6.12-9-powerpc
-rw-r--r-- 1 root root  248749 2006-05-23 16:10 abi-2.6.15-23-powerpc
-rw-r--r-- 1 root root  249070 2006-06-14 13:54 abi-2.6.15-25-powerpc
-rw-r--r-- 1 root root   46818 2006-04-28 15:21 config-2.6.12-10-powerpc
-rw-r--r-- 1 root root   46817 2005-10-10 16:25 config-2.6.12-9-powerpc
-rw-r--r-- 1 root root   57999 2006-05-23 15:45 config-2.6.15-23-powerpc
-rw-r--r-- 1 root root   57941 2006-06-14 13:25 config-2.6.15-25-powerpc
lrwxrwxrwx 1 root root      28 2006-06-18 09:41 initrd.img -> initrd.img-2.6.12-10-powerpc
-rw-r--r-- 1 root root 6452671 2006-06-04 14:32 initrd.img-2.6.12-10-powerpc
-rw-r--r-- 1 root root 6037811 2005-12-25 18:25 initrd.img-2.6.12-9-powerpc
-rw-r--r-- 1 root root 8096239 2006-06-04 20:10 initrd.img-2.6.15-23-powerpc
-rw-r--r-- 1 root root 8109776 2006-06-18 09:24 initrd.img-2.6.15-25-powerpc
lrwxrwxrwx 1 root root      28 2006-06-04 14:37 initrd.img.old -> initrd.img-2.6.15-23-powerpc
drwxr-xr-x 2 root root   12288 2005-12-25 17:48 lost+found
-rw-r--r-- 1 root root  822794 2006-04-28 15:44 System.map-2.6.12-10-powerpc
-rw-r--r-- 1 root root  822587 2005-10-10 16:47 System.map-2.6.12-9-powerpc
-rw-r--r-- 1 root root  667985 2006-05-23 16:10 System.map-2.6.15-23-powerpc
-rw-r--r-- 1 root root  660245 2006-06-14 13:54 System.map-2.6.15-25-powerpc
lrwxrwxrwx 1 root root      25 2006-06-18 09:41 vmlinux -> vmlinux-2.6.12-10-powerpc
-rw-r--r-- 1 root root 4135326 2006-04-28 15:44 vmlinux-2.6.12-10-powerpc
-rw-r--r-- 1 root root 4134050 2005-10-10 16:47 vmlinux-2.6.12-9-powerpc
-rw-r--r-- 1 root root 4262734 2006-05-23 16:10 vmlinux-2.6.15-23-powerpc
-rw-r--r-- 1 root root 4207671 2006-06-14 13:54 vmlinux-2.6.15-25-powerpc
lrwxrwxrwx 1 root root      25 2006-06-04 14:37 vmlinux.old -> vmlinux-2.6.15-23-powerpc

I can provide more detailed info (such as lshw) if you need.  I will
check back on this bug report.

Thanks for you time.
/Mike Hammill

** Affects: linux-source-2.6.15 (Ubuntu)
     Importance: Untriaged
         Status: Unconfirmed

-- 
2.6.15-xx ppc kernel fails to boot on G4
https://launchpad.net/bugs/50813