From: Paul Mackerras <paulus@samba.org>
To: torvalds@linux-foundation.org
Cc: linuxppc-dev@ozlabs.org, akpm@linux-foundation.org,
linux-kernel@vger.kernel.org
Subject: Please pull powerpc.git merge branch
Date: Fri, 28 Mar 2008 23:35:34 +1100 [thread overview]
Message-ID: <18412.58902.189124.391104@cargo.ozlabs.ibm.com> (raw)
Linus,
I have added another commit to the powerpc.git merge branch, so when
you do:
git pull \
git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc.git merge
you'll get a fix for a bug where the hardware data breakpoint would
sometimes fail to trigger on powerpc, if multiple threads put a
breakpoint on the same address. The bug has been around for a while
and Michael Ellerman just found the cause and posted a fix.
Thanks,
Paul.
arch/powerpc/configs/pasemi_defconfig | 142 ++++++++++++++++++++-------------
arch/powerpc/kernel/process.c | 10 +-
2 files changed, 93 insertions(+), 59 deletions(-)
commit a2ceff5e555e664751bc653a4d9b133efa18c742
Author: Michael Ellerman <michael@ellerman.id.au>
Date: Fri Mar 28 19:11:48 2008 +1100
[POWERPC] Fix missed hardware breakpoints across multiple threads
There is a bug in the powerpc DABR (data access breakpoint) handling,
which can result in us missing breakpoints if several threads are trying
to break on the same address.
The circumstances are that do_page_fault() calls do_dabr(), this clears
the DABR (sets it to 0) and sets up the signal which will report to
userspace that the DABR was hit. The do_signal() code will restore the DABR
value on the way out to userspace.
If we reschedule before calling do_signal(), __switch_to() will check the
cached DABR value and compare it to the new thread's value, if they match
we don't set the DABR in hardware.
So if two threads have the same DABR value, and we schedule from one to
the other after taking the interrupt for the first thread hitting the DABR,
the second thread will run without the DABR set in hardware.
The cleanest fix is to move the cache update into set_dabr(), that way we
can't forget to do it.
Reported-by: Jan Kratochvil <jan.kratochvil@redhat.com>
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
commit 5c29934de29ddd7ecd913d83cad28e872f2e8c78
Author: Olof Johansson <olof@lixom.net>
Date: Tue Mar 25 10:28:26 2008 -0500
[POWERPC] update pasemi_defconfig
Disable GEN_RTC since it conflicts with the i2c rtc drivers registering,
besides that keep most of the new defaults.
Signed-off-by: Olof Johansson <olof@lixom.net>
next reply other threads:[~2008-03-28 12:36 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-03-28 12:35 Paul Mackerras [this message]
2008-03-28 22:06 ` Bartlomiej Sieka
2008-04-01 23:12 ` Paul Mackerras
2008-04-02 4:27 ` Grant Likely
-- strict thread matches above, loose matches on Subject: below --
2008-04-03 11:33 Paul Mackerras
2008-03-27 23:08 Paul Mackerras
2008-03-25 3:32 Paul Mackerras
2008-03-24 8:05 Paul Mackerras
2008-03-20 0:43 Paul Mackerras
2008-03-12 23:51 Paul Mackerras
2008-03-03 11:41 Paul Mackerras
2008-03-03 15:44 ` Grant Likely
2008-02-20 3:46 Paul Mackerras
2008-02-21 12:15 ` Paul Mackerras
2008-02-14 22:00 Paul Mackerras
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=18412.58902.189124.391104@cargo.ozlabs.ibm.com \
--to=paulus@samba.org \
--cc=akpm@linux-foundation.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linuxppc-dev@ozlabs.org \
--cc=torvalds@linux-foundation.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
all inboxes | Powered by JetHome®