Date: Thu, 1 Jun 2017 22:03:14 +0200
From: Cyril Hrubis <chrubis@suse.cz>
To: Soheil Hassas Yeganeh <soheil@google.com>
Cc: "David S. Miller" <davem@davemloft.net>,
        Shmulik Ladkani <shmulik.ladkani@gmail.com>,
        Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>,
        Pravin B Shelar <pshelar@ovn.org>, Eric Dumazet <edumazet@google.com>,
        WANG Cong <xiyou.wangcong@gmail.com>,
        Yaogong Wang <wygivan@google.com>,
        Steffen Klassert <steffen.klassert@secunet.com>,
        Al Viro <viro@zeniv.linux.org.uk>, netdev <netdev@vger.kernel.org>,
        linux-kernel@vger.kernel.org
Subject: Re: commit f5f99309 (sock: do not set sk_err in
 sock_dequeue_err_skb) has broken ping
Message-ID: <20170601200314.GD10526@rei.suse.de>
References: <20170601140048.GA24401@rei.lan>
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Hi!
> Thank you very much! I have a wild guess that, when we
> have a train of skbs on the error queue starting from a local error,
> we will see this issue.
> 
> Ping (without my patch) considers EAGAIN on a normal read as an
> indication that there is nothing on the error queue, but that's a
> flawed assumption.
> 
> Would you mind trying another shot in the darkness please? Thanks!

This patch seems to fix the issue, I've tried several times and poll()
just timeouts, haven't seen a single POLLERR in the ping strace.

You can add my Tested-by: for this patch as well :-).

-- 
Cyril Hrubis
chrubis@suse.cz