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Message-ID: <e1cdc917-f18c-59df-0956-ffb1c16c2a9c@kernel.org>
Date: Wed, 2 Aug 2023 09:09:42 -0600
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Subject: Re: [PATCH net 4/6] tcp_metrics: annotate data-races around
 tm->tcpm_vals[]
Content-Language: en-US
To: Eric Dumazet <edumazet@google.com>, "David S . Miller"
 <davem@davemloft.net>, Jakub Kicinski <kuba@kernel.org>,
 Paolo Abeni <pabeni@redhat.com>
Cc: netdev@vger.kernel.org, eric.dumazet@gmail.com,
 Kuniyuki Iwashima <kuniyu@amazon.com>
References: <20230802131500.1478140-1-edumazet@google.com>
 <20230802131500.1478140-5-edumazet@google.com>
From: David Ahern <dsahern@kernel.org>
In-Reply-To: <20230802131500.1478140-5-edumazet@google.com>
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On 8/2/23 7:14 AM, Eric Dumazet wrote:
> tm->tcpm_vals[] values can be read or written locklessly.
> 
> Add needed READ_ONCE()/WRITE_ONCE() to document this,
> and force use of tcp_metric_get() and tcp_metric_set()
> 
> Fixes: 51c5d0c4b169 ("tcp: Maintain dynamic metrics in local cache.")
> Signed-off-by: Eric Dumazet <edumazet@google.com>
> ---
>  net/ipv4/tcp_metrics.c | 23 ++++++++++++++---------
>  1 file changed, 14 insertions(+), 9 deletions(-)
> 

Reviewed-by: David Ahern <dsahern@kernel.org>