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Date: Sun, 1 Mar 2015 21:50:09 +0000
To: freebsd-net@freebsd.org
From: "rpokala-panasas.com (Ravi Pokala)" <phabric-noreply@FreeBSD.org>
Subject: [Differential] [Commented On] D1986: Teach lagg(4) to change MTU
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Thread-Topic: D1986: Teach lagg(4) to change MTU
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rpokala-panasas.com added a comment.

>>! In D1986#4, @ae wrote:
> 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.

Don't the calls to LAGG_RLOCK() / LAGG_RUNLOCK() prevent that by enforcing serialization?

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

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