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Date: Sun, 1 Mar 2015 12:50:16 +0000
To: freebsd-net@freebsd.org
From: "ae (Andrey V. Elsukov)" <phabric-noreply@FreeBSD.org>
Subject: [Differential] [Changed Subscribers] D1986: Teach lagg(4) to change
 MTU
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Thread-Topic: D1986: Teach lagg(4) to change MTU
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ae added a subscriber: ae.
ae added a comment.

Just a thought. Imagine two interfaces, one has maximum MTU 2200, another 1500. lagg0 has MTU 1400.
Two threads invokes changing MTU in the same time. One wants to change it to 2000, another - to 1500.
It is possible, that when both threads will finish its job, one interface will have MTU 1400, but another - 1500.
I mean, that such changes should be done exclusively without possibility of races in the ioctl code.

REVISION DETAIL
  https://reviews.freebsd.org/D1986

To: rpokala-panasas.com, rstone
Cc: ae, freebsd-net