Copied to Christopher M. Riedl <c...@linux.ibm.com> and linuxppc list.
Le 22/10/2021 à 19:40, Stan Johnson a écrit :
Hello Christophe and Finn,
My message to Christopher Riedl bounced:
<c...@codefail.de>:
554: 5.7.1 <c...@codefail.de>: Relay access denied
I'm not sure how to proceed; thanks for any help.
You should always copy the list, as other people might be interested by
your problem and/or may help you.
Christophe
-Stan
-------- Forwarded Message --------
Subject: Fwd: X stopped working with 5.14 on iBook
Date: Fri, 22 Oct 2021 11:35:21 -0600
From: Stan Johnson <user...@yahoo.com>
To: Christopher M. Riedl <c...@codefail.de>
CC: Finn Thain <fth...@fastmail.com.au>
Hello Christopher Riedl,
Please see the message below, in which a git bisect identifies a commit
which may have stopped X from working on some PowerPC G4 systems
(specifically the G4 PowerBook and Cube, possibly others).
I'm not sure how to proceed with further tests. If the identified commit
could not have caused the problem, then further testing may be needed.
Please let me know if you need any additional information.
Hopefully your e-mail filter will allow messages from yahoo.com addresses.
thanks for your help
-Stan Johnson
user...@yahoo.com
-------- Forwarded Message --------
Subject: Re: X stopped working with 5.14 on iBook
Date: Fri, 22 Oct 2021 11:25:14 -0600
From: Stan Johnson <user...@yahoo.com>
To: debian-powe...@lists.debian.org
CC: Riccardo Mottola <riccardo.mott...@libero.it>
On 10/14/21 9:21 PM, Stan Johnson wrote:
...
Debian's 5.10.0-8 config file works (as expected) with Debian's 5.10.0-8
kernel source.
...
X works with 5.14 using a tuned config file derived from 5.13 testing.
...
Update:
The issue originally reported by Riccardo Mottola was that X wasn't
working on a PowerBook G4 using Debian's default
vmlinux-5.14.0-2-powerpc kernel. I was able to confirm that the X
failure also occurs on a G4 Cube. My G4 Cube has Debian SID,
sysvinit-core, Xfce and wdm installed. To test whether X works, I
disabled wdm, then I log in at the text console and run "startx". When X
fails, the screen goes blank and the backlight stays on; when X works,
the normal desktop comes up.
X works in mainline v5.12 built using a config file based on Debian's
config-5.10.0-8-powerpc.
X fails in mainline v5.13 built using a config file based on Debian's
config-5.10.0-8-powerpc.
With much help and advice from Finn Thain, I was able to run a bisect
using a config file based on Debian's config-5.10.0-8-powerpc, with
v5.12 "good" and v5.13 "bad".
$ git reset --hard
HEAD is now at 62fb9874f5da Linux 5.13
$ git bisect start v5.13
Updating files: 100% (12992/12992), done.
Previous HEAD position was 62fb9874f5da Linux 5.13
HEAD is now at 9f4ad9e425a1 Linux 5.12
$ git bisect bad v5.13
$ git bisect good v5.12
Bisecting: 8739 revisions left to test after this (roughly 13 steps)
85f3f17b5db2dd9f8a094a0ddc665555135afd22] Merge branch 'md-fixes' of
https://git.kernel.org/pub/scm/linux/kernel/git/song/md into block-5.13
After the bisect, git reports this:
----------
d3ccc9781560af051554017c702631560bdc0811 is the first bad commit
commit d3ccc9781560af051554017c702631560bdc0811
Author: Christopher M. Riedl <c...@codefail.de>
Date: Fri Feb 26 19:12:59 2021 -0600
powerpc/signal: Use __get_user() to copy sigset_t
Usually sigset_t is exactly 8B which is a "trivial" size and does not
warrant using __copy_from_user(). Use __get_user() directly in
anticipation of future work to remove the trivial size optimizations
from __copy_from_user().
The ppc32 implementation of get_sigset_t() previously called
copy_from_user() which, unlike __copy_from_user(), calls access_ok().
Replacing this w/ __get_user() (no access_ok()) is fine here since both
callsites in signal_32.c are preceded by an earlier access_ok().
Signed-off-by: Christopher M. Riedl <c...@codefail.de>
Signed-off-by: Michael Ellerman <m...@ellerman.id.au>
Link: https://lore.kernel.org/r/20210227011259.11992-11-...@codefail.de
arch/powerpc/kernel/signal.h | 7 +++++++
arch/powerpc/kernel/signal_32.c | 2 +-
arch/powerpc/kernel/signal_64.c | 4 ++--
3 files changed, 10 insertions(+), 3 deletions(-)
