From: subas...@codeaurora.org
Date: Tue, 2 Feb 2016 02:11:10 -0000
> A rcu stall with the following backtrace was seen on a system with
> forwarding, optimistic_dad and use_optimistic set. To reproduce,
> set these flags and allow ipv6 autoconf.
>
> This occurs because the device write_lock is acquired while already
> holding the read_lock. Back trace below -
...
> v2: do addrconf_dad_kick inside read lock and then acquire write
> lock for ipv6_ifa_notify as suggested by Eric
>
> Fixes: 7fd2561e4ebdd ("net: ipv6: Add a sysctl to make optimistic
> addresses useful candidates")
>
> Cc: Eric Dumazet <eduma...@google.com>
> Cc: Erik Kline <e...@google.com>
> Cc: Hannes Frederic Sowa <han...@stressinduktion.org>
> Signed-off-by: Subash Abhinov Kasiviswanathan <subas...@codeaurora.org>
Applied and queued up for -stable, thanks.
