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[Xen-devel] [PATCH][IOEMU]Attempt to setup tap interface up to 3 times.

To: "xen-devel" <xen-devel@xxxxxxxxxxxxxxxxxxx>, "Keir Fraser" <keir@xxxxxxxxxxxxx>
Subject: [Xen-devel] [PATCH][IOEMU]Attempt to setup tap interface up to 3 times.
From: "Petersson, Mats" <Mats.Petersson@xxxxxxx>
Date: Thu, 17 May 2007 16:35:07 +0200
Delivery-date: Thu, 17 May 2007 07:34:36 -0700
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Thread-topic: [PATCH][IOEMU]Attempt to setup tap interface up to 3 times.
Resend: Now with patch attached.

As there is a (small) chance that vl.c:tap_open() fails (due to some
sort of race-condition in the Linux kernel, which is noted as a bug in
the source .../net/core/dev.c), we should attempt it again a couple of
times if it doesn't succeed on the first attempt. I think three times in
total is sufficient to avoid the problem. 

If tap_open() fails, qemu-dm will exit, which means that the domain dies
- which is not such a good thing when attempting to restore a saved
domain [of course, it would be even worse if it started, but didn't have
networking - because there may not be a way to shut it down cleanly
without network]. 

Attached is an updated patch to the one I sent a few days ago, which
matches the latest Xen-unstable. 

Signed off by: Mats Petersson (mats.petersson@xxxxxxx)


Attachment: patch.try_tap_3_times
Description: patch.try_tap_3_times

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