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Bug 376831

Summary: Read from /proc/ppc64/rtas/error_log does not honor O_NONBLOCK
Product: Red Hat Enterprise Linux 5 Reporter: Qian Cai <qcai>
Component: kernelAssignee: Vitaly Mayatskikh <vmayatsk>
Status: CLOSED ERRATA QA Contact: Martin Jenner <mjenner>
Severity: low Docs Contact:
Priority: low    
Version: 5.1CC: bpeters, bugproxy, dzickus, jburke, mgahagan, syeghiay
Target Milestone: rc   
Target Release: ---   
Hardware: ppc64   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2009-01-20 20:26:34 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:
Attachments:
Description Flags
Proposed patch none

Description Qian Cai 2007-11-12 01:57:33 UTC
Description of problem:
After open(2) on /proc/ppc64/rtas/error_log with O_NONBLOCK flag, read(2) the
file is blocked, and waited on an event.

Version-Release number of selected component (if applicable):
RHEL5.1-Server

How reproducible:
Always

Steps to Reproduce:
1. open ("/proc/ppc64/rtas/error_log", O_RDONLY | O_NONBLOCK);
2. read (fd, buf, 4096); 
  
Actual results:
read(2) is blocked.

Expected results:
read(2) shall return EAGAIN.

Comment 1 Vitaly Mayatskikh 2008-07-10 13:07:50 UTC
RHEL-3 and RHEL-4 have the same problem, btw

Comment 2 Linda Wang 2008-07-31 18:13:42 UTC
patch posted on 7/10. dev ack. 

Request exception since this bug was found by QE in 5.2 testing.


Comment 3 RHEL Program Management 2008-07-31 18:22:33 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 4 IBM Bug Proxy 2008-09-12 19:30:37 UTC
Created attachment 316612 [details]
Proposed patch

Comment 5 Brad Peters 2008-09-12 19:49:55 UTC
For completeness - Vitaly had posted upstream here:

http://post-office.corp.redhat.com/archives/rhkernel-list/2008-July/msg00225.html

Comment 6 Brad Peters 2008-09-12 19:50:32 UTC
Last link was RH-internal; here's the upstream post:

http://lkml.org/lkml/2008/7/4/112

Comment 9 Don Zickus 2008-10-29 16:17:37 UTC
in kernel-2.6.18-121.el5
You can download this test kernel from http://people.redhat.com/dzickus/el5

Comment 13 errata-xmlrpc 2009-01-20 20:26:34 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-2009-0225.html