Bug 131886
| Summary: | __put_task_struct unresolved when loading externally compiled module | ||||||
|---|---|---|---|---|---|---|---|
| Product: | Red Hat Enterprise Linux 3 | Reporter: | Robin Crook <robin> | ||||
| Component: | kernel | Assignee: | Ernie Petrides <petrides> | ||||
| Status: | CLOSED ERRATA | QA Contact: | Brian Brock <bbrock> | ||||
| Severity: | medium | Docs Contact: | |||||
| Priority: | medium | ||||||
| Version: | 3.0 | CC: | petrides, riel | ||||
| Target Milestone: | --- | Keywords: | FutureFeature | ||||
| Target Release: | --- | ||||||
| Hardware: | i686 | ||||||
| OS: | Linux | ||||||
| Whiteboard: | |||||||
| Fixed In Version: | RHSA-2005-663 | Doc Type: | Enhancement | ||||
| Doc Text: | Story Points: | --- | |||||
| Clone Of: | Environment: | ||||||
| Last Closed: | 2005-09-28 14:29:35 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: | |||||||
| Bug Blocks: | 156320 | ||||||
| Attachments: |
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can you give a pointer to the sourcecode of this module so that we can see what you are trying to achieve ? Created attachment 103507 [details]
tar file of sources
I've attached a tarfile of the sources. The put_task_struct call is in the
rms_kern.c file.
We are in the process of removing the need to use a
patch (that we call ptrack) that provides containers
for the set of processes in a parallel job. One of
the operations we perform is to accumulate its stats.
We increment the reference count on the proc so that
it doesn't disappear under our feet, we do this with
get_task_struct (rms_kern.c:453). We decrement the
reference count with free_task_struct (or put_task_struct
in some kernels) when we are finished with the process
(rms_kern.c:583).
This all works ok on 2.4.20 and vanilla 2.6 kernels
but not on RHEL 3.0 where the put_task_struct macro
exists but the __put_task_struct fn is not defined.
This bug is present in the 2.6.7 vanilla kernel as well and I've found this by googling: http://www.ussg.iu.edu/hypermail/linux/kernel/0308.0/0666.html From: Frank Cornelis (Frank.Cornelis.be) Date: Mon Aug 04 2003 - 07:54:13 EST Next message: Alan Cox: "Re: DVD-RAM errors (was: DVD-RAM crashing system Hi, In order to be able to safely manipulate a task_struct from within a module one should use get/put_task_struct. This is currently not possible because __put_task_struct is not exported. Next patch solves this issue. Frank. --- linux-2.6.0-test2.orig/kernel/ksyms.c 2003-07-29 10:04:45.000000000 +0200 +++ linux-2.6.0-test2/kernel/ksyms.c 2003-07-29 14:11:40.000000000 +0200 @@ -495,6 +495,7 @@ #if !defined(__ia64__) EXPORT_SYMBOL(loops_per_jiffy); #endif +EXPORT_SYMBOL(__put_task_struct); /* misc */ We would really like this patch to make it into the distribution. Patch posted for review on 29-Apr-2005. A fix for this problem has just been committed to the RHEL3 U6 patch pool this evening (in kernel version 2.4.21-32.3.EL). 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 the 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-2005-663.html |
From Bugzilla Helper: User-Agent: Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.0) Description of problem: I have compiled a module against the 2.4.21-15.0.3.EL linux kernel source tree. Initially I got the following when I tried to load it: [root@stratum11 rms]# insmod ./rms.o ./rms.o: unresolved symbol free_task_struct Googling resulted in me changing free_task_struct to put_task_struct but I now get: [root@stratum11 rms]# insmod ./rms.o ./rms.o: unresolved symbol __put_task_struct [root@stratum11 rms]# Version-Release number of selected component (if applicable): kernel-smp-2.4.21-15.0.3.EL How reproducible: Always Steps to Reproduce: 1. Include a call to put_task_struct(tsk) in module code and build it against the 2.4.21-15.0.3.EL source tree 2. try to insmod the module - insmod ./rms.o 3. Actual Results: [root@stratum11 rms]# insmod ./rms.o ./rms.o: unresolved symbol __put_task_struct [root@stratum11 rms]# Expected Results: The module should have loaded. Additional info: