Re: [PATCH iproute2 0/2] fix "ip link show dev ..." for NICs with many VFs

From: Stephen Hemminger
Date: Fri Sep 01 2017 - 17:16:47 EST


On Fri, 1 Sep 2017 18:39:06 +0200 (CEST)
Michal Kubecek <mkubecek@xxxxxxx> wrote:

> Two of our customers recently encountered problems with processing of large
> messages produced by kernel in response to "ip link show" for NICs with
> many (120-128) virtual functions. While some of them have been already
> addressed in recent versions of iproute2, some still persist.
>
> Patch 1 adds check to handle the case when a message fits into the
> buffer in rtnl_talk() but not into the buffer in iplink_get().
>
> Patch 2 increases the buffer size in iplink_get() to suffice even for
> NICs with 128 VFs.
>
> Note: after applying patch 2, patch 1 seems useless as both buffers have
> the same size so that the check cannot actually trigger. However, as we
> cannot guarantee they will always stay the same, I believe the check
> should still be added.
>
> Michal Kubecek (2):
> iplink: check for message truncation in iplink_get()
> iplink: double the buffer size also in iplink_get()
>
> ip/iplink.c | 7 ++++++-
> 1 file changed, 6 insertions(+), 1 deletion(-)
>

Looks like the best set of solutions to the kernel side API issue.
Applied, thanks Michal.