Bug 1300542
| Summary: | If mmap() of /dev/mem fails, librtas does not release /run/lock/LCK..librtas | ||
|---|---|---|---|
| Product: | Red Hat Enterprise Linux 7 | Reporter: | David Gibson <dgibson> |
| Component: | librtas | Assignee: | Sinny Kumari <skumari> |
| Status: | CLOSED ERRATA | QA Contact: | Release Test Team <release-test-team-automation> |
| Severity: | medium | Docs Contact: | |
| Priority: | unspecified | ||
| Version: | 7.3 | CC: | bharata.rao, bugproxy, dgibson, dhorak, hannsj_uhl, jstodola, mbanas, secondary-arch-list, skumari |
| Target Milestone: | rc | Keywords: | Patch |
| Target Release: | 7.3 | ||
| Hardware: | ppc64le | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | librtas-1.4.1-1.el7 | Doc Type: | Bug Fix |
| Doc Text: |
Cause: When librtas fails, RMO buffer lock were not released in error path
Consequence: In certain cases (like fails to mmap() the RTAS RMO buffer from /dev/mem) if librtas fails, causes future librtas invocations to jam
Fix: Update to librtas-1.4.1-1.el7 or higher version
Result:
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Story Points: | --- |
| Clone Of: | Environment: | ||
| Last Closed: | 2016-11-04 04:01:38 UTC | Type: | Bug |
| 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: | 1182039 | ||
| Bug Blocks: | 1230910, 1274397 | ||
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Description
David Gibson
2016-01-21 06:17:39 UTC
Sorry, left out version: librtas-1.3.13-2.el7.ppc64le But I believe this is the same in latest upstream librtas as well. The mentioned upstream kernels implement CONFIG_STRICT_DEVMEM, which, due to a kernel bug, prohibits librtas from mmaping() the range of /dev/mem it needs. Obviously that kernel bug needs to be dealth with elsewhere, but librtas should still release the lock on the failure path. Sorry, on further investigation, it's not clear that all the listed kernels will trigger the bug. Kernel 9fa686068a32ddf256df03982b3e3967c18654a8 does appear to trigger it reliably, though. ------- Comment From hegdevasant.com 2016-03-10 10:14 EDT------- I think below commit on kernel side resolves this issue. commit e256caa7d0515e301f8c8c6e7d1204a2b67b1381 Author: Vasant Hegde <hegdevasant.ibm.com> Date: Thu Jan 21 21:45:31 2016 +0530 powerpc/mm: Allow user space to map rtas_rmo_buf With commit 90a545e9 (restrict /dev/mem to idle io memory ranges) mapping rtas_rmo_buf from user space is failing. Hence we are not able to make RTAS syscall. This patch calls page_is_rtas_user_buf before calling iomem_is_exclusive in devmem_is_allowed(). This will allow user space to map rtas_rmo_buf and we are able to make RTAS syscall. Reported-by: Bharata B Rao <bharata.ibm.com> CC: Nathan Fontenot <nfont.ibm.com> Signed-off-by: Vasant Hegde <hegdevasant.ibm.com> Acked-by: Dan Williams <dan.j.williams> Signed-off-by: Michael Ellerman <mpe.au> -Vasant ------- Comment From hegdevasant.com 2016-03-10 10:16 EDT------- ..and librtas fix . Note that its in origin/next branch.. it will eventually goes to master.. So you can pull this patch . commit c5e9dcf993e9e20bbe14bc06fb0ec6dd5031f935 Author: Vasant Hegde <hegdevasant.ibm.com> Date: Mon Feb 15 07:33:14 2016 -0500 librtas: Release lock in error path Release RMO buffer lock in error path. Otherwise we will continue to hold the lock and subsequent RMO buffer allocation request fails. Reported-by: Bharata B Rao <bharata.ibm.com> Signed-off-by: Vasant Hegde <hegdevasant.ibm.com> -Vasant ------- Comment From hegdevasant.com 2016-03-10 10:17 EDT------- Hello RedHat, Please lets know if you still have issue after applying these patches?. -Vasant Sinny, can you backport / merge that librtas patch? Sure, we will backport this patch in librtas, RHEL 7.3. Also, let us know if a new upstream release of librtas occur with fix included. (In reply to Sinny Kumari from comment #6) > Sure, we will backport this patch in librtas, RHEL 7.3. . ... yes, for RHEL7.3 a librtas update is requested in LTC bug 120225 - RH1182039- [7.3 FEAT] librtas package update - ppc64/ppc64le . > Also, let us know if a new upstream release of librtas occur with fix > included. . ... I will check ... (In reply to Hanns-Joachim Uhl from comment #7) > (In reply to Sinny Kumari from comment #6) > > Sure, we will backport this patch in librtas, RHEL 7.3. > . > ... yes, for RHEL7.3 a librtas update is requested in > LTC bug 120225 - RH1182039- [7.3 FEAT] librtas package update - ppc64/ppc64le > . > > Also, let us know if a new upstream release of librtas occur with fix > > included. > . > ... I will check ... . fyi ... the librtas patch from this bugzilla is included in "librtas 1.4.1" as available upstream from https://github.com/nfont/librtas/releases ... (In reply to Hanns-Joachim Uhl from comment #8) > fyi ... the librtas patch from this bugzilla is included in "librtas 1.4.1" > as available upstream from > https://github.com/nfont/librtas/releases ... Thanks for update. Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA. For information on the advisory, and where to find the updated files, follow the link below. If the solution does not work for you, open a new bug report. https://rhn.redhat.com/errata/RHBA-2016-2337.html |