Bug 485904
| Summary: | [RHEL4] Netfilter modules unloading hangs | ||||||
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| Product: | Red Hat Enterprise Linux 4 | Reporter: | Tomas Smetana <tsmetana> | ||||
| Component: | kernel | Assignee: | Jiri Pirko <jpirko> | ||||
| Status: | CLOSED ERRATA | QA Contact: | Evan McNabb <emcnabb> | ||||
| Severity: | medium | Docs Contact: | |||||
| Priority: | medium | ||||||
| Version: | 4.7 | CC: | anton, davem, mgahagan, nhorman, rkhan, tao, tgraf, tumeya, vgoyal | ||||
| Target Milestone: | rc | ||||||
| Target Release: | --- | ||||||
| Hardware: | All | ||||||
| OS: | Linux | ||||||
| Whiteboard: | |||||||
| Fixed In Version: | Doc Type: | Bug Fix | |||||
| Doc Text: | Story Points: | --- | |||||
| Clone Of: | 485903 | Environment: | |||||
| Last Closed: | 2011-02-16 16:01:01 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: | |||||||
| Bug Depends On: | 485903 | ||||||
| Bug Blocks: | |||||||
| Attachments: |
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Description
Tomas Smetana
2009-02-17 11:44:08 UTC
Were you using some special routing table to reproduce this bug? I have tried on both rhel 4.8 (-81 kernel) as well as rhel 5 (-130 and -92 kernels) and was unable to reproduce the problem. (In reply to comment #1) > Were you using some special routing table to reproduce this bug? I have tried > on both rhel 4.8 (-81 kernel) as well as rhel 5 (-130 and -92 kernels) and was > unable to reproduce the problem. Yes. Sorry, I forgot to mention. I had to 'route add 192.168.122.254 dev eth0' on the testing system to reproduce the behaviour. I could have sworn I had tried that, figuring you had to have done something to the routing table to reproduce this. It reproduces for me in rhel 5.3, I'll try rhel 4 in a bit, but I'll go ahead and give this a qa ack. Created attachment 332725 [details]
reproducer script
reproducer script, updated to add a route to the non existant host needed to reproduce the bug.
Since RHEL 4.8 External Beta has begun, and this bugzilla remains unresolved, it has been rejected as it is not proposed as exception or blocker. I apologize Jiri, I've been busy with other bugs, I'll look at this today My first thought, looking at this bug is that I'd like to confirm what we're seeing. I see the origional comment that we're spinning in the cleanup code. I think thats quite likely accurate, but it would be nice to have something confirming it here. A sysrq-t showing that stack trace would be good towards that end. Also, it would be nice if we could get the contents of /proc/net/netfilter/ip_conntrack and ip_conntrack_expect. That will tell us a bit more about who isn't getting cleaned from the various lists during cleanup given the reproducer, what I _think_ might be happening is that we're incrementing the ip_conntrack_count for entries when we create them, but before we put them on the ip_conntrack_hash lists. Since we only clean the latter, the addition of a route to an unreachable destination prevents us from ever confirming the conntrack entry, so we can never clean it, and never remove the module. Thats just a theory though, the above data will help confirm it. please use rhel5 bz to make comments - bz485903 ...setting dependency I made a mistake in the name of the proc files though, its nfs_conntrack and nf_contract_expect you want to examine before and after the hang. My expectation is that we're seeing something get on the expect list, holding a reference, but never transition to the nf_conntrack list, so it never gets clean. Thats likely what we need to look at. 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. Committed in 89.43.EL . RPMS are available at http://people.redhat.com/vgoyal/rhel4/ Some errors/confusions while adding the bz to errata tool. Returning bz to MODIFIED state so that it can be added to errata. 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-2011-0263.html |