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Mon, 17 Aug 2026 05:14:52 -0700 (PDT) From: Yiqi Sun To: jk@codeconstruct.com.au Cc: davem@davemloft.net, edumazet@google.com, horms@kernel.org, kuba@kernel.org, linux-kernel@vger.kernel.org, matt@codeconstruct.com.au, netdev@vger.kernel.org, pabeni@redhat.com, qwe.aldo@gmail.com, sunyiqixm@gmail.com Subject: Re: Re: [PATCH] net: mctp: hold a reference to the route device in mctp_route_lookup() Date: Mon, 17 Aug 2026 20:14:32 +0800 Message-Id: <20260817121432.3586534-1-sunyiqixm@gmail.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <55cd94e61d68d95e9db16f21980a532f4edf70e1.camel@codeconstruct.com.au> References: <55cd94e61d68d95e9db16f21980a532f4edf70e1.camel@codeconstruct.com.au> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Hi Jeremy, > Hi Aldo, > > > mctp_route_lookup() uses rt->dev without holding a reference on it. > > [...] > > > Take a reference with refcount_inc_not_zero() before touching rt->dev, > > skip a device that is already dead, and drop the reference once the > > destination has taken its own. > > This looks the same as Yiqi Sun's analysis: > > https://lore.kernel.org/netdev/20260731022926.913865-1-sunyiqixm@gmail.co= > m/ > > I had requested some simplifications for the proposed fix, which would > likely result in something very close to your contribution here. > > Yiqi had not followed up from that review as yet, though; so if we don't > see any updated patch shortly, then your implementation looks reasonable. > > Regards, > > > Jeremy Sorry for the delay. I haven't had a chance to send v2 yet. I've reviewed Aldo's patch, and the approach looks good to me. It addresses the same issue I was trying to fix, so I'm happy for Aldo's patch to supersede mine. Thanks for picking this up, Aldo, and thanks for the review, Jeremy. Regards, Yiqi