Received-SPF: pass (google.com: domain of linux-kernel+bounces-29986-linux.lists.archive=gmail.com@vger.kernel.org designates 147.75.199.223 as permitted sender) client-ip=147.75.199.223;
Date: Thu, 18 Jan 2024 17:55:41 +0800
From: Hangbin Liu <liuhangbin@gmail.com>
To: Taehee Yoo <ap420073@gmail.com>
Cc: Nikita Zhandarovich <n.zhandarovich@fintech.ru>,
	"David S. Miller" <davem@davemloft.net>,
	David Ahern <dsahern@kernel.org>,
	Eric Dumazet <edumazet@google.com>,
	Jakub Kicinski <kuba@kernel.org>, Paolo Abeni <pabeni@redhat.com>,
	netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
	syzbot+a9400cabb1d784e49abf@syzkaller.appspotmail.com
Subject: Re: [PATCH net] ipv6: mcast: fix data-race in ipv6_mc_down /
 mld_ifc_work
Message-ID: <Zaj1nZRBkWaDfo-e@Laptop-X1>
References: <20240117172102.12001-1-n.zhandarovich@fintech.ru>
 <ZaiQs6yTY7XuS06i@Laptop-X1>
 <bac390f1-ef6d-317f-a5e1-1c0c5e4e4535@gmail.com>
Precedence: bulk
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <bac390f1-ef6d-317f-a5e1-1c0c5e4e4535@gmail.com>

On Thu, Jan 18, 2024 at 04:24:52PM +0900, Taehee Yoo wrote:
> > I saw mld_process_v1() also cancel these works when changing to v1 mode.
> > Should we also add lock there?
> 
> I think mld_process_v1() doesn't have a problem.
> Because mld_process_v1() is always called under mc_lock by mld_query_work().
> 
> mld_query_work()
>    mutex_lock(&idev->mc_lock);
>     __mld_query_work();
>        mld_process_v1();
>    mutex_unlock(&idev->mc_lock);

Thanks for this info, then this works for me.

Hangbin