A customer ran across this in a -128.el5 kernel. The reclaimer thread is stuck in flush_workqueue(): 10.0.11.43-re D 0000000000000000 12512 14208 515 13543 (L-T Call Trace: [C0000000017475B0] [C000000000565D28] 0xc000000000565d28 (unreliable) [C000000001747780] [C000000000010ACC] .__switch_to+0x124/0x148 [C000000001747810] [C0000000003C6454] .schedule+0xbfc/0xdb0 [C000000001747920] [C000000000081DE0] .flush_cpu_workqueue+0xbc/0x140 [C0000000017479E0] [C000000000081EFC] .flush_workqueue+0x98/0xe0 [C000000001747A70] [D000000000D2545C] .xs_connect+0x108/0x128 [sunrpc] [C000000001747B00] [D000000000D240FC] .xprt_connect+0x194/0x1bc [sunrpc] [C000000001747BA0] [D000000000D21F34] .call_connect+0xa0/0xc0 [sunrpc] [C000000001747C30] [D000000000D2841C] .__rpc_execute+0xec/0x344 [sunrpc] [C000000001747CD0] [D000000000D20E84] .rpc_call_sync+0xac/0x100 [sunrpc] [C000000001747D70] [D000000000F3D18C] .nfs4_proc_renew+0x68/0xe0 [nfs] [C000000001747E20] [D000000000F4CBD8] .reclaimer+0x80/0x3a4 [nfs] [C000000001747EE0] [C000000000087248] .kthread+0x128/0x178 [C000000001747F90] [C0000000000274C4] .kernel_thread+0x4c/0x68 The problem is that there's a hung events thread that looks like this: events/5 D 0000000000000000 9792 31 1 32 30 (L-TLB) Call Trace: [C0000001DFDB77D0] [C0000001D9430C00] 0xc0000001d9430c00 (unreliable) [C0000001DFDB79A0] [C000000000010ACC] .__switch_to+0x124/0x148 [C0000001DFDB7A30] [C0000000003C6454] .schedule+0xbfc/0xdb0 [C0000001DFDB7B40] [C0000000003C8C10] .rwsem_down_read_failed+0x27c/0x2c4 [C0000001DFDB7C10] [C00000000008B06C] .down_read+0x44/0x5c [C0000001DFDB7CA0] [D000000000F4DED8] .nfs4_renew_state+0x3c/0x270 [nfs] [C0000001DFDB7D50] [C0000000000819D0] .run_workqueue+0xdc/0x168 [C0000001DFDB7DF0] [C00000000008273C] .worker_thread+0x12c/0x19c [C0000001DFDB7EE0] [C000000000087248] .kthread+0x128/0x178 [C0000001DFDB7F90] [C0000000000274C4] .kernel_thread+0x4c/0x68 The renewal thread is holding the semaphore that the events thread needs to complete its work. Deadlock. I believe the flush_workqueue() call in xs_connect() is no longer needed and should have been removed as part of the fix for bug 448754.
Event posted on 2009-07-27 19:52 EDT by Glen Johnson ------- Comment From emachado.ibm.com 2009-07-27 19:43 EDT------- Hello Jeff (@Red Hat), per previous conversation with Frank Filz, he mentioned there is a bug on RHEL5.4 kernel (and probably upstream as well) affecting NFSv4 clients which is hard to reproduce on RHEL5.4 beta releases but is more likely to occur with the test kernel you provided (2.6.18-138.el5.jtltest.74). So, we were wondering if you would know of any other patches in this test kernel that might have made such problem more prone to occur. FYI, this bug in question was mirrored over Red Hat as RHIT 315313 (LTC bug 54383). Thank you very much for your support. Ticket type changed from 'Problem' to '' This event sent from IssueTracker by balkov issue 283765
Event posted on 2009-08-04 14:15 EDT by Glen Johnson ------- Comment From ffilz.com 2009-08-04 14:05 EDT------- The test kernel from Red Hat seems to make it easy to hit a deadlock condition reported in bug 54383. The deadlock has otherwise not been hit. We tried applying this patch to RHEL 5.4 beta but were unable to re-create the deadlock. This event sent from IssueTracker by balkov issue 283765
Event posted on 2009-08-04 20:21 EDT by Glen Johnson ------- Comment From ffilz.com 2009-08-04 20:13 EDT------- Could we possibly get a RHEL 5.4 based test kernel with this fix so we can test it and perhaps see if we can avoid bug 54383? This event sent from IssueTracker by balkov issue 283765
This request was evaluated by Red Hat Product Management for inclusion in a Red Hat Enterprise Linux maintenance release. Product Management has requested further review of this request by Red Hat Engineering, for potential inclusion in a Red Hat Enterprise Linux Update release for currently deployed products. This request is not yet committed for inclusion in an Update release.
@GSS, We need to confirm that there is commitment to test for the resolution of this request during the RHEL 5.5 test phase, if it is accepted into the release. Please post a confirmation before Oct 16th, 2009, including the contact information for testing engineers.
in kernel-2.6.18-172.el5 You can download this test kernel from http://people.redhat.com/dzickus/el5 Please do NOT transition this bugzilla state to VERIFIED until our QE team has sent specific instructions indicating when to do so. However feel free to provide a comment indicating that this fix has been verified.
~~ Attention Customers and Partners - RHEL 5.5 Beta is now available on RHN ~~ RHEL 5.5 Beta has been released! There should be a fix present in this release that addresses your request. Please test and report back results here, by March 3rd 2010 (2010-03-03) or sooner. Upon successful verification of this request, post your results and update the Verified field in Bugzilla with the appropriate value. If you encounter any issues while testing, please describe them and set this bug into NEED_INFO. If you encounter new defects or have additional patch(es) to request for inclusion, please clone this bug per each request and escalate through your support representative.
Event posted on 2010-03-04 12:11 EST by Glen Johnson ------- Comment From kumarr.com 2010-03-04 12:03 EDT------- (In reply to comment #33) > IBM; > Need test results or this will be dropped from 5.5. Red Hat, I just talked to the submitter. He'll be verifying this fix ASAP. We'll post the results and let you know. Thanks for the reminder. Internal Status set to 'Waiting on Support' Status set to: Waiting on Tech This event sent from IssueTracker by balkov issue 283765
@Glen, @IBM, any update?
An advisory has been issued which should help the problem described in this bug report. This report is therefore being closed with a resolution of ERRATA. For more information on therefore solution and/or where to find the updated files, please follow the link below. You may reopen this bug report if the solution does not work for you. http://rhn.redhat.com/errata/RHSA-2010-0178.html