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a=6eWqkTHjU83fiwn7nKZWdM+Sl24=:19 a=z/mQ4Ysz8XfWz/Q5cLBRGdckG28=:19 a=lCpzRmAYbLLaTzLvsPZ7Mbvzbb8=:19 a=xqWC_Br6kY4A:10 a=IkcTkHD0fZMA:10 a=Yq5XynenixoA:10 a=VkNPw1HP01LnGYTKEx00:22 a=7x6HtfJdh03M6CCDgxCd:22 a=_78whYxrdx1mplLwxq1U:22 a=aYmhyGnNTLQyLaClKr0A:9 a=QEXdDO2ut3YA:10 a=ZXulRonScM0A:10 a=zZCYzV9kfG8A:10 X-Proofpoint-ORIG-GUID: 30gBvH8gjCgvFSt9-VAtZMQefOQ0KxIN X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1143,Hydra:6.1.51,FMLib:17.12.100.49 definitions=2026-03-07_04,2026-03-06_02,2025-10-01_01 On 3/5/26 5:33 PM, Paolo Abeni wrote: > > As noted by Micheal in the previous revision the above will > skb->truesize under accounting. That is not safe and at least need a > solid explaination, which is still missing. I misunderstood Michael's v9 feedback as a variable naming issue and only added a separate alloc_len to avoid clobbering len, without actually propagating the real allocation size to truesize. page_pool_alloc_va() can return more than requested when the remaining page fragment is too small for another allocation. The small buffer path ignores this and reconstructs buflen from constants in receive_small_build_skb(), so build_skb() sets truesize based on the requested size, not the actual allocation. I'll fix this in v11 by encoding the actual allocation size in the ctx pointer (similar to how the mergeable path uses mergeable_len_to_ctx) so receive_small_build_skb() can pass the real buflen to build_skb(). > > /P >