From: David Miller <davem@davemloft.net>
To: guru2018@gmail.com
Cc: netdev@vger.kernel.org, kuznet@ms2.inr.ac.ru, yoshfuji@linux-ipv6.org
Subject: Re: [PATCH]ipv6: multicast: In mld_send_cr function moving read lock to second for loop
Date: Sat, 18 Aug 2018 13:58:19 -0700 (PDT) [thread overview]
Message-ID: <20180818.135819.1279366350823380240.davem@davemloft.net> (raw)
In-Reply-To: <CAHSpA5-ivVaQnQU7_ikt=BV-EAwFJFaA6ErpQ1Jn1HmPmXZapg@mail.gmail.com>
From: Guruswamy Basavaiah <guru2018@gmail.com>
Date: Fri, 17 Aug 2018 18:01:41 +0530
> @@ -1860,7 +1860,6 @@ static void mld_send_cr(struct inet6_dev *idev)
> struct sk_buff *skb = NULL;
> int type, dtype;
>
> - read_lock_bh(&idev->lock);
> spin_lock(&idev->mc_lock);
>
> /* deleted MCA's */
This will lead to deadlocks, idev->mc_lock must be taken with _bh().
I have zero confidence in this change, did you do any stress testing
with lockdep enabled? It would have caught this quickly.
next prev parent reply other threads:[~2018-08-19 0:07 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <CAHSpA58KdjMLnnGdbyDbASJLFuf2BHLsADBuO1jeT_1uFp9GUA@mail.gmail.com>
2018-08-17 12:31 ` [PATCH]ipv6: multicast: In mld_send_cr function moving read lock to second for loop Guruswamy Basavaiah
2018-08-18 20:58 ` David Miller [this message]
2018-09-18 13:21 ` Guruswamy Basavaiah
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