Bug 431907
| Summary: | 5.2: service iscsi stop on a busy target causes a soft CPU lockup on ppc64. | ||||||
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| Product: | Red Hat Enterprise Linux 5 | Reporter: | Barry Donahue <bdonahue> | ||||
| Component: | kernel | Assignee: | David Howells <dhowells> | ||||
| Status: | CLOSED WONTFIX | QA Contact: | Red Hat Kernel QE team <kernel-qe> | ||||
| Severity: | medium | Docs Contact: | |||||
| Priority: | medium | ||||||
| Version: | 5.2 | CC: | bdonahue, bpeters, dhoward | ||||
| Target Milestone: | rc | ||||||
| Target Release: | --- | ||||||
| Hardware: | ppc64 | ||||||
| OS: | Linux | ||||||
| Whiteboard: | |||||||
| Fixed In Version: | Doc Type: | Bug Fix | |||||
| Doc Text: | Story Points: | --- | |||||
| Clone Of: | Environment: | ||||||
| Last Closed: | 2014-08-22 23:13:12 UTC | Type: | --- | ||||
| Regression: | --- | Mount Type: | --- | ||||
| Documentation: | --- | CRM: | |||||
| Verified Versions: | Category: | --- | |||||
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |||||
| Cloudforms Team: | --- | Target Upstream Version: | |||||
| Embargoed: | |||||||
| Attachments: |
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Created attachment 294258 [details]
It a piece of the /var/log/messages file with several examples of the lockup.
Can you run with a kernel that has LOCKDEP enabled? That might determine what is causing CPUs to get stuck. The log is a bit weird: there appear to be soft lockups occurring in vprintk(). This suggests that either someone's holding the spinlock and not letting go, or that another CPU is hammering the printk's so hard that the faulting CPU isn't getting a look in. If this is running in a virtual partition on a ppc64 machine, then the yield-to-hypervisor nature of spinlocks there may be exacerbating the situation. This is not a blocker or RHEL 5.2. Moving out to RHEL 5.2 for further investigation. This request was evaluated by Red Hat Product Management for inclusion, but this component is not scheduled to be updated in the current Red Hat Enterprise Linux release. If you would like this request to be reviewed for the next minor release, ask your support representative to set the next rhel-x.y flag to "?". Unfortunately the previous automated notification about the non-inclusion of this request in Red Hat Enterprise Linux 5.3 used the wrong text template. It should have read: this request has been reviewed by Product Management and is not planned for inclusion in the current minor release of Red Hat Enterprise Linux. If you would like this request to be reviewed for the next minor release, ask your support representative to set the next rhel-x.y flag to "?" or raise an exception. This bug/component is not included in scope for RHEL-5.11.0 which is the last RHEL5 minor release. This Bugzilla will soon be CLOSED as WONTFIX (at the end of RHEL5.11 development phase (Apr 22, 2014)). Please contact your account manager or support representative in case you need to escalate this bug. That sounds like the best plan. |
Description of problem: If you install the 20080206.nightly on a ppc64 box with the latest iscsi-initiator-utils, executing service iscsi stop on a busy target will cause a soft lockup. Version-Release number of selected component (if applicable): kernel: 2.6.18-77.el5 iscsi: iscsi-initiator-utils-6.2.0.868-0.3.el5 How reproducible:Every time Steps to Reproduce: 1. Install 5.2 2. Install latest iscsi-initiator-utils 3. Add this to /etc/iscsi/iscsid.conf: node.conn[0].iscsi.HeaderDigest = None 4. --login to the target build files systen and mount it. 5. Do IO to iscsi LUN and the do service iscsi stop. Actual results: You will encounter a soft lokup. Target system was ibm-js21-01.lab.boston.redhat.com. Expected results: We should only get some IO errors on the iscsi LUN. Additional info: Actual test script was: #!/bin/bash let "x=1" while [ $x -lt 100 ] do mount /dev/sdb1 /mnt/sdb status=$? if [ $status != 0 ]; then echo "Mount FAILED" exit fi dd if=/dev/zero of=/mnt/sdb/file bs=1024 count=1000000& echo "x=$x" sleep 5 service iscsi stop umount /mnt/sdb service iscsi start sleep 5 let x++ done