RHEL Engineering is moving the tracking of its product development work on RHEL 6 through RHEL 9 to Red Hat Jira (issues.redhat.com). If you're a Red Hat customer, please continue to file support cases via the Red Hat customer portal. If you're not, please head to the "RHEL project" in Red Hat Jira and file new tickets here. Individual Bugzilla bugs in the statuses "NEW", "ASSIGNED", and "POST" are being migrated throughout September 2023. Bugs of Red Hat partners with an assigned Engineering Partner Manager (EPM) are migrated in late September as per pre-agreed dates. Bugs against components "kernel", "kernel-rt", and "kpatch" are only migrated if still in "NEW" or "ASSIGNED". If you cannot log in to RH Jira, please consult article #7032570. That failing, please send an e-mail to the RH Jira admins at rh-issues@redhat.com to troubleshoot your issue as a user management inquiry. The email creates a ServiceNow ticket with Red Hat. Individual Bugzilla bugs that are migrated will be moved to status "CLOSED", resolution "MIGRATED", and set with "MigratedToJIRA" in "Keywords". The link to the successor Jira issue will be found under "Links", have a little "two-footprint" icon next to it, and direct you to the "RHEL project" in Red Hat Jira (issue links are of type "https://issues.redhat.com/browse/RHEL-XXXX", where "X" is a digit). This same link will be available in a blue banner at the top of the page informing you that that bug has been migrated.
Bug 1321875 - blktrace attempts to start threads on offline CPUs
Summary: blktrace attempts to start threads on offline CPUs
Keywords:
Status: CLOSED WONTFIX
Alias: None
Product: Red Hat Enterprise Linux 6
Classification: Red Hat
Component: blktrace
Version: 6.8
Hardware: ppc64
OS: Linux
medium
medium
Target Milestone: rc
: ---
Assignee: Eric Sandeen
QA Contact: BaseOS QE Security Team
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2016-03-29 10:00 UTC by Milos Malik
Modified: 2017-03-04 17:52 UTC (History)
1 user (show)

Fixed In Version:
Doc Type: Bug Fix
Doc Text:
Clone Of:
Environment:
Last Closed: 2016-05-19 17:40:04 UTC
Target Upstream Version:
Embargoed:


Attachments (Terms of Use)

Description Milos Malik 2016-03-29 10:00:09 UTC
Description of problem:
 * either blktrace guesses the number of CPUs incorrectly or it is not able to run on more 32 CPUs

Version-Release number of selected component (if applicable):
RHEL-6.7
blktrace-1.0.1-7.el6.ppc64
kernel-2.6.32-573.el6.ppc64
kernel-bootwrapper-2.6.32-573.el6.ppc64
kernel-devel-2.6.32-573.el6.ppc64
kernel-firmware-2.6.32-573.el6.noarch
kernel-headers-2.6.32-573.el6.ppc64

How reproducible:
always

Steps to Reproduce:
# dmesg | grep -i cpus
Partition configured for 64 cpus.
Initializing cgroup subsys cpuset
Brought up 32 CPUs
Node 0 CPUs: 0-31
# mount -t debugfs debugfs /sys/kernel/debug/
#blktrace -w 1 -d /dev/sda 

Actual results:
FAILED to start thread on CPU 32: 22/Invalid argument
FAILED to start thread on CPU 33: 22/Invalid argument
FAILED to start thread on CPU 34: 22/Invalid argument
FAILED to start thread on CPU 35: 22/Invalid argument
FAILED to start thread on CPU 36: 22/Invalid argument
FAILED to start thread on CPU 37: 22/Invalid argument
FAILED to start thread on CPU 38: 22/Invalid argument
FAILED to start thread on CPU 39: 22/Invalid argument
FAILED to start thread on CPU 40: 22/Invalid argument
FAILED to start thread on CPU 41: 22/Invalid argument
FAILED to start thread on CPU 42: 22/Invalid argument
FAILED to start thread on CPU 43: 22/Invalid argument
FAILED to start thread on CPU 44: 22/Invalid argument
FAILED to start thread on CPU 45: 22/Invalid argument
FAILED to start thread on CPU 46: 22/Invalid argument
FAILED to start thread on CPU 47: 22/Invalid argument
FAILED to start thread on CPU 48: 22/Invalid argument
FAILED to start thread on CPU 49: 22/Invalid argument
FAILED to start thread on CPU 50: 22/Invalid argument
FAILED to start thread on CPU 51: 22/Invalid argument
FAILED to start thread on CPU 52: 22/Invalid argument
FAILED to start thread on CPU 53: 22/Invalid argument
FAILED to start thread on CPU 54: 22/Invalid argument
FAILED to start thread on CPU 55: 22/Invalid argument
FAILED to start thread on CPU 56: 22/Invalid argument
FAILED to start thread on CPU 57: 22/Invalid argument
FAILED to start thread on CPU 58: 22/Invalid argument
FAILED to start thread on CPU 59: 22/Invalid argument
FAILED to start thread on CPU 60: 22/Invalid argument
FAILED to start thread on CPU 61: 22/Invalid argument
FAILED to start thread on CPU 62: 22/Invalid argument
FAILED to start thread on CPU 63: 22/Invalid argument

Expected results:
# cat /sys/devices/system/cpu/online
0-31
# cat /sys/devices/system/cpu/offline 
32-1023

* blktrace runs on all CPUs which are online and it doesn't complain about the others

Comment 3 Eric Sandeen 2016-03-29 16:06:39 UTC
So the root problem is that it is trying to start threads on offline CPUs?

Comment 4 Eric Sandeen 2016-03-29 16:23:09 UTC
commit 80c4041b2e7a7d5afb75df563bf51bb27773c095
Author: Abutalib Aghayev <agayev>
Date:   Tue Feb 9 08:17:50 2016 -0700

    blktrace: Use number of online CPUs
    
    Currently, blktrace uses _SC_NPROCESSORS_CONF to find out the number of
    CPUs.  This is a problem, because if you reduce the number of online
    CPUs by passing kernel parameter maxcpus, then blktrace fails to start
    with the error:
    
    FAILED to start thread on CPU 4: 22/Invalid argument
    FAILED to start thread on CPU 5: 22/Invalid argument
    ...
    
    The attached patch fixes it to use _SC_NPROCESSORS_ONLN.
    
    Signed-off-by: Jens Axboe <axboe>

Comment 5 Karel Srot 2016-04-01 06:28:00 UTC
Postponing to rhel-6.9 as it is too late to address this bug in rhel-6.8.

Comment 6 Eric Sandeen 2016-05-19 17:40:04 UTC
Sadly I don't think we'll be able to ship this fix at this point in rhel6.


Note You need to log in before you can comment on or make changes to this bug.