Bug 520867

Summary: glibc should call pselect() and ppoll() on ia64 kernel
Product: Red Hat Enterprise Linux 5 Reporter: Fabio Olive Leite <fleite>
Component: kernelAssignee: Prarit Bhargava <prarit>
Status: CLOSED ERRATA QA Contact: Red Hat Kernel QE team <kernel-qe>
Severity: medium Docs Contact:
Priority: medium    
Version: 5.3CC: cward, dzickus, moshiro, prarit, tao
Target Milestone: rc   
Target Release: ---   
Hardware: ia64   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2010-03-30 07:38:47 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: ---
Bug Depends On:    
Bug Blocks: 533192, 526775    
Attachments:
Description Flags
Simple reproducer.
none
Correct x86_64 pselect() call.
none
Incorrect ia64 pselect() emulated by glibc.
none
RHEL5 fix for this issue none

Description Fabio Olive Leite 2009-09-02 18:07:59 UTC
Created attachment 359564 [details]
Simple reproducer.

Description of problem:

Since bug 206806 was fixed in 2.6.18-98.el5 the ia64 kernel implements the pselect() and ppoll() syscalls. glibc is still not using them as of RHEL-5.3 and instead emulates it with the racy equivalent.

Version-Release number of selected component (if applicable):

glibc-2.5-34

How reproducible:

Always.

Steps to Reproduce:

1. Compile and run test program attached.

Actual results:

Pending signals are caught at sigprocmask() time and then select() may block forever, in the racy pselect() "equivalent".

Expected results:

Use the actual pselect() syscall that will then return pending signals and not block forever.

Additional info:

x86_64 and ia64 straces of the test program will be attached.

Comment 1 Fabio Olive Leite 2009-09-02 18:08:41 UTC
Created attachment 359565 [details]
Correct x86_64 pselect() call.

Comment 2 Fabio Olive Leite 2009-09-02 18:09:41 UTC
Created attachment 359566 [details]
Incorrect ia64 pselect() emulated by glibc.

Comment 3 Andreas Schwab 2009-09-03 09:06:40 UTC
This is a bug in kernel-headers, it needs to define the syscalls.
glibc then just needs to be rebuilt against the fixed kernel-headers and it will magically pick up the syscalls.

Comment 5 Prarit Bhargava 2009-09-17 15:37:54 UTC
Created attachment 361518 [details]
RHEL5 fix for this issue

Patch that resolves this issue.

Tested by doing

1.  compile reproducer with existing glibc.  Test fails.

2.  apply patch to tree, and install kernel-headers.

3.  rebuild glibc rpms

4.  reinstall glibc rpms

5.  compile reproducer.  Test succeeds:

[root@altix4 tmp]# ./doit 
Calling pselect.
Test succeeded.

Comment 10 RHEL Product and Program Management 2009-09-25 17:38:14 UTC
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.

Comment 11 Don Zickus 2009-10-06 19:39:15 UTC
in kernel-2.6.18-168.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.

Comment 14 Chris Ward 2010-02-11 10:25:43 UTC
~~ 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.

Comment 17 Prarit Bhargava 2010-03-28 12:27:59 UTC
Clearing stale NEEDINFO request.

Comment 18 errata-xmlrpc 2010-03-30 07:38:47 UTC
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