Bug 499202 - New compilation warning in ext4 rebase
Summary: New compilation warning in ext4 rebase
Keywords:
Status: CLOSED ERRATA
Alias: None
Product: Red Hat Enterprise Linux 5
Classification: Red Hat
Component: kernel
Version: 5.4
Hardware: All
OS: Linux
low
medium
Target Milestone: rc
: ---
Assignee: Eric Sandeen
QA Contact: Red Hat Kernel QE team
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2009-05-05 15:25 UTC by Eric Sandeen
Modified: 2009-09-02 08:57 UTC (History)
2 users (show)

Fixed In Version:
Doc Type: Bug Fix
Doc Text:
Clone Of:
Environment:
Last Closed: 2009-09-02 08:57:28 UTC
Target Upstream Version:
Embargoed:


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System ID Private Priority Status Summary Last Updated
Red Hat Product Errata RHSA-2009:1243 0 normal SHIPPED_LIVE Important: Red Hat Enterprise Linux 5.4 kernel security and bug fix update 2009-09-01 08:53:34 UTC

Description Eric Sandeen 2009-05-05 15:25:13 UTC
(A bit embarrasing, I re-introduced this after fixing it in 5.3, during the rebase - setting "regression" for this reason).

The ext4 code generates a warning when built on x86:

fs/ext4/inode.c: In function 'ext4_do_update_inode':
fs/ext4/inode.c:3047: warning: right shift count >= width of type

This is because upstream, the vfs i_version is a long long, but in rhel5 it's
only a long (so 32 bits on 32 bit machines) and we over-shift in that case.

Even though a 32-bit i_version might not be terribly useful for the intended
purpose, this should probably be fixed to avoid unexpected results.

Thanks,
-Eric

Index: rhel5-kernel/fs/ext4/inode.c
===================================================================
--- rhel5-kernel.orig/fs/ext4/inode.c	2008-09-22 13:30:02.000000000 -0500
+++ rhel5-kernel/fs/ext4/inode.c	2008-09-22 14:55:39.493001278 -0500
@@ -3043,8 +3043,13 @@ static int ext4_do_update_inode(handle_t
 	raw_inode->i_disk_version = cpu_to_le32(inode->i_version);
 	if (ei->i_extra_isize) {
 		if (EXT4_FITS_IN_INODE(raw_inode, ei, i_version_hi))
+			/* in RHEL5 i_version is an unsigned long */
+#if BITS_PER_LONG == 64
 			raw_inode->i_version_hi =
 			cpu_to_le32(inode->i_version >> 32);
+#else
+			raw_inode->i_version_hi = 0;
+#endif
 		raw_inode->i_extra_isize = cpu_to_le16(ei->i_extra_isize);
 	}

Comment 1 RHEL Program Management 2009-05-05 15:29:08 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 Don Zickus 2009-05-12 17:41:49 UTC
in kernel-2.6.18-146.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 8 errata-xmlrpc 2009-09-02 08:57:28 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-2009-1243.html


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