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From: "Jason A. Donenfeld" <Jason@zx2c4.com>
Date: Sun, 6 Nov 2016 12:20:34 +0100
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Subject: Re: [WireGuard] mips32 crash
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> <7>[13905.531148] wireguard: Sending handshake initiation to peer 1 (x.x.x.x:16)
> <4>[13905.629622] ------------[ cut here ]------------

So you said the crash 100% occurs 100ms after sending handshake
initiation. If related this could be because:

a) The scheduler ticks come in 100ms intervals. In this case, the
crash would be caused by something in sending the initiation.
or
b) The ping latency is 100ms. In this case, the crash would be caused
by something in receiving the response.
or
c) Something else.

I'm curious: when the crash happens, does the ARM box receive the
handshake initiation message?