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From: Roman Mamedov <rm@romanrm.net>
To: kvm@vger.kernel.org
Subject: [BUG] vhost-net: Enabling experimental_zcopytx always crashes the host on 5.10, worked fine on 5.4
Date: Thu, 24 Jun 2021 21:28:25 +0500	[thread overview]
Message-ID: <20210624212825.32aaa6f9@natsu> (raw)

Hello,

I am upgrading my VM host from 5.4.126 to 5.10.46.
The host started crashing almost instantly after boot.

The issue is traced down to:

If the vhost-net module is loaded with "experimental_zcopytx=1", as soon as a
Windows KVM guest boots up and starts doing even a light network load
(watching YouTube), the entire host crashes with a backtrace pointing to
skb_segment, parts of which I was able to capture.

This is reproducible 100% of the time, got 3 identical crashes before getting
a capture and then flipping the parameter to 0. With it set to 0 the issue
goes away.

Reported at [1], not sure if that was the best place for the report, thought
maybe posting here as well won't hurt.

Thanks

[1] https://bugzilla.kernel.org/show_bug.cgi?id=213563

-- 
With respect,
Roman

                 reply	other threads:[~2021-06-24 16:30 UTC|newest]

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