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[Xen-devel] [BUG] race condition in blkfront (probably other frontends t

To: Xen Development Mailing List <xen-devel@xxxxxxxxxxxxxxxxxxx>
Subject: [Xen-devel] [BUG] race condition in blkfront (probably other frontends too).
From: Gerd Hoffmann <kraxel@xxxxxxxxxx>
Date: Thu, 24 Jul 2008 16:15:07 +0200
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  Hi folks,

I've just seen it with the block frontend, but most likely the other
frontend drivers are affected too.  The blkfront drivers goes into
initialized state (in blkfront_probe), and *after* that xenbus_dev_probe
sets a watch on the state node of the device.  That leaves a race window
open for the backend going into connected state before the watch is
active.  If that happens the frontend doesn't notice the backend is
ready and never ever goes into connected state ...

cheers,
  Gerd

-- 
http://kraxel.fedorapeople.org/xenner/

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