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[73.158.218.242]) by smtp.gmail.com with UTF8SMTPSA id d2e1a72fcca58-748e61679c5sm2327505b3a.84.2025.06.18.14.38.08 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 18 Jun 2025 14:38:09 -0700 (PDT) Date: Wed, 18 Jun 2025 14:38:08 -0700 From: Stanislav Fomichev To: Jakub Kicinski Cc: Mina Almasry , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, "David S. Miller" , Eric Dumazet , Paolo Abeni , Simon Horman , ap420073@gmail.com Subject: Re: [PATCH net v1] netmem: fix skb_frag_address_safe with unreadable skbs Message-ID: References: <20250617210950.1338107-1-almasrymina@google.com> <20250618142740.65203c69@kernel.org> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20250618142740.65203c69@kernel.org> On 06/18, Jakub Kicinski wrote: > On Tue, 17 Jun 2025 14:52:17 -0700 Mina Almasry wrote: > > > > Sorry, I realized right after hitting send, I'm missing: > > > > > > > > Fixes: 9f6b619edf2e ("net: support non paged skb frags") > > > > > > > > I can respin after the 24hr cooldown. > > > > > > The function is used in five drivers, none of which support devmem tx, > > > does not look like there is a reason to route it via net. > > > > > > The change it self looks good, but not really sure it's needed. > > > skb_frag_address_safe is used in some pass-data-via-descriptor-ring mode, > > > I don't see 'modern' drivers (besides bnxt which added this support in 2015) > > > use it. > > > > Meh, a judgement call could be made here. I've generally tried to > > make sure skb helpers are (unreadable) netmem compatible without a > > thorough analysis of all the callers to make sure they do or will one > > day use (unreadable) netmem. Seems better to me to fix this before > > some code path that plumbs unreadable memory to the helper is actually > > merged and that code starts crashing. > > Fair points, tho I prefer the simple heuristic of "can it trigger on > net", otherwise it's really easy to waste time pondering each single > patch. I'll apply to net-next as is. Stanislav, do you want to ack? Sure, SG! Acked-by: Stanislav Fomichev