On Mon, 8 Aug 2016, Christian Kujau wrote:
> while trying to upgrade this PowerBook G4 from 4.7-rc7 to 4.8-rc1, it's
> unable to boot the Yaboot (v1.3.16 from Debian/stable) boot loader:
>
> ================================================================
> copying OF device tree...
> Building dt strings...
> Building dt stucture...
> Device tree strings 0x01e72000 -> 0x01e73615
> Device tree struct 0x01e74000 -> 0x01e7e000
> Quiescing Open Firmware...
> Bootng Linux via __start()...
>
> Invalid memory access at $SRR0: 0140f86c $SRR1: 00003030
>
> Apple PowerBook6,8 4.9.0f0 BootROM built on 01/10/05 at 10:39:14
> [...]
>
> ok
> 0:> _
> ================================================================
>
> Going back to 4.7-rc7 (w/o installing Yaboot again) works just fine. The
> config is mostly the same (used "make oldconfig" from 4.7), but I've said
> YES to CONFIG_SLAB_FREELIST_RANDOM - could this be causing the boot
> failure? Full .config and screen shot: http://nerdbynature.de/bits/4.8.0-rc1/
A git-bisect led me to:
=========================================
commit 9402c684613163888714df0955fa1f17142b08bf
Author: Benjamin Herrenschmidt <b...@kernel.crashing.org>
Date: Tue Jul 5 15:03:41 2016 +1000
powerpc: Factor do_feature_fixup calls
32 and 64-bit do a similar set of calls early on, we move it all to
a single common function to make the boot code more readable.
Signed-off-by: Benjamin Herrenschmidt <b...@kernel.crashing.org>
Signed-off-by: Michael Ellerman <m...@ellerman.id.au>
=========================================
But I'm unable to revert just this patch:
$ git revert 9402c684613163888714df0955fa1f17142b08bf
error: could not revert 9402c68... powerpc: Factor do_feature_fixup calls
hint: after resolving the conflicts, mark the corrected paths
The bisect-log:
=========================================
$ git bisect log
git bisect start '--' 'arch/powerpc'
# good: [523d939ef98fd712632d93a5a2b588e477a7565e] Linux 4.7
git bisect good 523d939ef98fd712632d93a5a2b588e477a7565e
# bad: [29b4817d4018df78086157ea3a55c1d9424a7cfc] Linux 4.8-rc1
git bisect bad 29b4817d4018df78086157ea3a55c1d9424a7cfc
# bad: [3808a88985b4f5f5e947c364debce4441a380fb8] powerpc: Move FW feature
probing out of pseries probe()
git bisect bad 3808a88985b4f5f5e947c364debce4441a380fb8
# good: [a203658b5ed37c11e5016d3fbbbab9ce018c1b78] powerpc/opal: Wake up kopald
polling thread before waiting for events
git bisect good a203658b5ed37c11e5016d3fbbbab9ce018c1b78
# good: [0dfffb48cecd8f84c6e649baee9bacd9be925734] powerpc/powernv: abstraction
for saving SPRs before entering deep idle states
git bisect good 0dfffb48cecd8f84c6e649baee9bacd9be925734
# good: [66c570f545e056babdd9510595ce762dcedadd71] powerpc/mm: use _raw variant
of page table accessors
git bisect good 66c570f545e056babdd9510595ce762dcedadd71
# good: [c2ca9f6b4cc4c45eb598b24b8b06beee668052d5] powerpc/powernv: Fix
pci-cxl.c build when CONFIG_MODULES=n
git bisect good c2ca9f6b4cc4c45eb598b24b8b06beee668052d5
# good: [4c91bd6eeabb004f283db8a6854b134e2a2de1bc] powerpc: Merge the
RELOCATABLE config entries for ppc32 and ppc64
git bisect good 4c91bd6eeabb004f283db8a6854b134e2a2de1bc
# bad: [c4bd6cb87c9e28a7d9f4a97db5a06cc538eb5e48] powerpc: Move 64-bit feature
fixup earlier
git bisect bad c4bd6cb87c9e28a7d9f4a97db5a06cc538eb5e48
# bad: [9402c684613163888714df0955fa1f17142b08bf] powerpc: Factor
do_feature_fixup calls
git bisect bad 9402c684613163888714df0955fa1f17142b08bf
# good: [27d1149667352772240655b65372a4294f992ea7] powerpc/32: Remove
RELOCATABLE_PPC32
git bisect good 27d1149667352772240655b65372a4294f992ea7
# first bad commit: [9402c684613163888714df0955fa1f17142b08bf] powerpc: Factor
do_feature_fixup calls
=========================================
HTH,
Christian.
--
BOFH excuse #409:
The vulcan-death-grip ping has been applied.
