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Date: Mon, 12 Aug 2024 18:40:21 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Kuniyuki Iwashima <kuniyu@amazon.com>
Cc: Nicolas Ferre <nicolas.ferre@microchip.com>, Claudiu Beznea
 <claudiu.beznea@tuxon.dev>, "David S. Miller" <davem@davemloft.net>, "Eric
 Dumazet" <edumazet@google.com>, Paolo Abeni <pabeni@redhat.com>, Vineeth
 Karumanchi <vineeth.karumanchi@amd.com>, Kuniyuki Iwashima
 <kuni1840@gmail.com>, <netdev@vger.kernel.org>
Subject: Re: [PATCH v1 net] net: macb: Use rcu_dereference() for
 idev->ifa_list in macb_suspend().
Message-ID: <20240812184021.4a7abc18@kernel.org>
In-Reply-To: <20240808040021.6971-1-kuniyu@amazon.com>
References: <20240808040021.6971-1-kuniyu@amazon.com>
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On Wed, 7 Aug 2024 21:00:21 -0700 Kuniyuki Iwashima wrote:
> In macb_suspend(), idev->ifa_list is fetched with rcu_access_pointer()
> and later the pointer is dereferenced as ifa->ifa_local.
> 
> So, idev->ifa_list must be fetched with rcu_dereference().

I don't see where this driver takes rcu_read_lock, but
__in_dev_get_rcu() will already splat so we're not making 
it any worse.