netdev - [iproute PATCH] libnetlink: Double the dump buffer size

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Date:	Fri,  4 Mar 2016 19:57:28 +0100
From:	Phil Sutter <phil@....cc>
To:	Stephen Hemminger <shemming@...cade.com>
Cc:	netdev@...r.kernel.org
Subject: [iproute PATCH] libnetlink: Double the dump buffer size

There have been reports about 'ip addr' printing "Message truncated" on
systems with large numbers of VFs. Although I haven't been able to get
my hands on hardware suitable to reproduce this, increasing the dump
buffer has been reported to resolve the issue. For want of a better
idea, just double the buffer size to 32k.

Feels like this opportunistic buffer size selection is rather
workarounding a design flaw in libnetlink or maybe even the netlink
protocol itself.

Signed-off-by: Phil Sutter <phil@....cc>
---
 lib/libnetlink.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/libnetlink.c b/lib/libnetlink.c
index d6b5fd3e8a493..245c4ca216753 100644
--- a/lib/libnetlink.c
+++ b/lib/libnetlink.c
@@ -223,7 +223,7 @@ int rtnl_dump_filter_l(struct rtnl_handle *rth,
 		.msg_iov = &iov,
 		.msg_iovlen = 1,
 	};
-	char buf[16384];
+	char buf[32768];
 	int dump_intr = 0;

 	iov.iov_base = buf;
-- 
2.7.2