From: Paul Jackson <pj@sgi.com>
To: travis@sgi.com
Cc: linux-mm@kvack.org, ak@suse.de, linux-kernel@vger.kernel.org,
linuxppc-dev@ozlabs.org, sparclinux@vger.kernel.org,
akpm@linux-foundation.org, clameter@sgi.com
Subject: Re: [PATCH 08/10] ia64: Convert cpu_sibling_map to a per_cpu data array (v3)
Date: Fri, 28 Sep 2007 02:49:01 -0700 [thread overview]
Message-ID: <20070928024901.24ab6c99.pj@sgi.com> (raw)
In-Reply-To: <20070912015647.214306428@sgi.com>
Mike,
I think there is a bug either in this ia64 patch, or in the related
generic arch patch: Convert cpu_sibling_map to be a per cpu variable
(v3).
It dies early in boot on me, on the SGI internal 8 processor IA64
system that you and I know as 'margin'. The death is a hard hang, due
to a corrupt stack, due to a bogus cpu index.
I haven't tracked it down all the way, but have gotten this far. If I add
the following patch, I get a panic on the BUG_ON if I have these two patches
in 2.6.23-rc8-mm1, but it boots just fine if I don't have these two patches.
It seems that the "cpu_sibling_map[cpu]" cpumask_t is empty (all zero
bits) with your two patches applied, but has some non-zero bits
otherwise, which leads to 'group' being NR_CPUS instead of a useful CPU
number. Unfortunately, I have no idea why the "cpu_sibling_map[cpu]"
cpumask_t is empty -- good luck on that part.
The patch that catches this bug earlier is this:
--- 2.6.23-rc8-mm1.orig/kernel/sched.c 2007-09-28 01:42:20.144561024 -0700
+++ 2.6.23-rc8-mm1/kernel/sched.c 2007-09-28 02:27:14.239075497 -0700
@@ -5905,6 +5905,7 @@ static int cpu_to_phys_group(int cpu, co
#else
group = cpu;
#endif
+ BUG_ON(group == NR_CPUS);
if (sg)
*sg = &per_cpu(sched_group_phys, group);
return group;
--
I won't rest till it's the best ...
Programmer, Linux Scalability
Paul Jackson <pj@sgi.com> 1.925.600.0401
next prev parent reply other threads:[~2007-09-28 9:49 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-09-12 1:56 [PATCH 00/10] x86: Reduce Memory Usage and Inter-Node message traffic (v3) travis
2007-09-12 1:56 ` [PATCH 01/10] x86: remove x86_cpu_to_log_apicid array (v3) travis
2007-09-12 1:56 ` [PATCH 02/10] x86: fix cpu_to_node references (v3) travis
2007-09-12 1:56 ` [PATCH 03/10] x86: Convert cpu_core_map to be a per cpu variable (v3) travis
2007-09-12 1:56 ` [PATCH 04/10] x86: Convert cpu_sibling_map " travis
2007-09-12 1:56 ` [PATCH 05/10] x86: Convert x86_cpu_to_apicid " travis
2007-09-12 1:56 ` [PATCH 06/10] x86: Convert cpu_llc_id " travis
2007-09-12 1:56 ` [PATCH 07/10] x86: acpi-use-cpu_physical_id (v3) travis
2007-09-12 1:56 ` [PATCH 08/10] ia64: Convert cpu_sibling_map to a per_cpu data array (v3) travis
2007-09-28 9:49 ` Paul Jackson [this message]
2007-10-03 19:22 ` Mike Travis
2007-09-12 1:56 ` [PATCH 09/10] ppc64: " travis
2007-09-17 6:28 ` Stephen Rothwell
2007-09-17 6:39 ` Stephen Rothwell
2007-09-17 15:22 ` Mike Travis
2007-09-12 1:56 ` [PATCH 10/10] sparc64: " travis
2007-09-13 9:53 ` [PATCH 00/10] x86: Reduce Memory Usage and Inter-Node message traffic (v3) Andi Kleen
2007-09-14 23:32 ` Andrew Morton
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=20070928024901.24ab6c99.pj@sgi.com \
--to=pj@sgi.com \
--cc=ak@suse.de \
--cc=akpm@linux-foundation.org \
--cc=clameter@sgi.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=linuxppc-dev@ozlabs.org \
--cc=sparclinux@vger.kernel.org \
--cc=travis@sgi.com \
/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;
as well as URLs for NNTP newsgroup(s).