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Re: [Xen-devel] [PATCH] Fix stubdom-dm using "grep" improperly

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Subject: Re: [Xen-devel] [PATCH] Fix stubdom-dm using "grep" improperly
From: John Weekes <lists.xen@xxxxxxxxxxxxxxxxxx>
Date: Sun, 09 Jan 2011 23:34:38 -0800
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On 1/9/2011 9:09 PM, John Weekes wrote:
stubdom-dm uses "grep" on "xm list" output to determine whether it is already running. The existing behavior is to use "grep $domname-dm" but this will result in a false-positive in the case of another domU running whose name ends with the full new name; for instance, if "abctest-dm" is running, a new "test-dm" will spin forever, waiting for it the end.

Any easy fix is to have it use "grep -w" instead of "grep", searching for the whole word only.

It also might be worth considering a switch to "xl list" from "xm list", here and in other places.

This bug appears to exist in xen-4.0-testing, as well.

Since it's a one-liner, a signed-off may not be needed, but just in case..

Signed-off-by: John Weekes <lists.xen@xxxxxxxxxxxxxxxxxx>

Here's a corrected version done against the repo (i.e., with corrected paths).

diff -r 7b4c82f07281 stubdom/stubdom-dm
--- a/stubdom/stubdom-dm        Wed Jan 05 23:54:15 2011 +0000
+++ b/stubdom/stubdom-dm        Mon Jan 10 02:28:48 2011 -0500
@@ -91,7 +91,7 @@
 # stubdomain
 # Wait for any previous stubdom to terminate
-while xm list | grep $domname-dm
+while xm list | grep -w $domname-dm
        sleep 1


Attachment: stubdom-dm.patch
Description: Text Data

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