From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pf1-f176.google.com (mail-pf1-f176.google.com [209.85.210.176]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 081E04F7CB2 for ; Mon, 12 Oct 2026 21:27:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.176 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791840425; cv=none; b=GwoCqpozpWPbnFEZvFO1goLl33vKAcUgLFcVhiLsXcfx7bQbZAMWu3zF4y6rgz+ScgQajaAI7rsf4R+CgEIWyLwlrz7IJgqynHBe/2I38udFMQjDNSg2x4T5kyjlNHfn7QyNqjIa1nV1PSVC3F4N58meCrx/QsbVMFTvkjVE1tw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791840425; c=relaxed/simple; bh=vFCTPi6RkqhF5HPuqeIigpw8olvShpvLUVqeUIoJdYg=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=pSvUJPE4N/L/+duKKo0sqJLF7Vz0sJ464Ls9foEh3D21AtKsHM85U29IOM+l0Am/dKDpgWIDkvzIBBWuZRbb4BloyhQ4hgewFe12y0RYunzKmght6BFhlVqtrqvtpdU5YSldcDen/fmQ+bq+eZLegb1y7q8EKw0krPIq3bCrhlQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=dama.to; spf=none smtp.mailfrom=dama.to; dkim=pass (2048-bit key) header.d=dama-to.20251104.gappssmtp.com header.i=@dama-to.20251104.gappssmtp.com header.b=UuPUM0He; arc=none smtp.client-ip=209.85.210.176 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=dama.to Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=dama.to Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=dama-to.20251104.gappssmtp.com header.i=@dama-to.20251104.gappssmtp.com header.b="UuPUM0He" Received: by mail-pf1-f176.google.com with SMTP id d2e1a72fcca58-881269371acso2062311b3a.0 for ; Mon, 12 Oct 2026 14:27:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=dama-to.20251104.gappssmtp.com; s=20251104; t=1791840423; x=1792445223; darn=vger.kernel.org; h=in-reply-to:content-disposition:content-type:mime-version :references:mail-followup-to:message-id:subject:cc:to:from:date:from :to:cc:subject:date:message-id:reply-to:content-type; bh=00lr0ueSHjjLFpqBUflLoQS+JH73YrWnwKwvoX92I9o=; b=UuPUM0HeTJ/ADEIghcha+FZah2r1LoSTx/oKR1mcAhddvveQVx+4banNqP2RU3CsTY LJ++V2f0XycCs4OQM6j3dOCi6hmgN3I4a8ATKZmItwuAeFCIyAYiX63tMUmNaQWXeqxA FRo9JNB3KvPQjw97HmOqQMAZsH5OM2xHx1E5PcmH8ODMIXZOgEV9UHxwryORjEAM539C k1h4aIjiBHEEI6b3aCwPPZBxbriyEzUxl4P+CQQYn7av7Rx1194ZgGy+P1sOpMKVKiVa o5B4e38Yv9ieFFKRRqYzydXFevulTXLoTGVb6YqtbgNIWFIv7Wy51EHhDGn3CIb8oRyR +13w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1791840423; x=1792445223; h=in-reply-to:content-disposition:content-type:mime-version :references:mail-followup-to:message-id:subject:cc:to:from:date :x-gm-gg:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to:content-type; bh=00lr0ueSHjjLFpqBUflLoQS+JH73YrWnwKwvoX92I9o=; b=yHZHAh8isOWC7qfz6JSYxoFtk+xKoug6g0wpTw/DstBBgZ4ntwPp8c6MH8dDiR6Z74 C5K8WbgkANkiDQD1IjWf13owJnO0wCDaaaG5V+UygHTsMV1SUwWTH27OaYmw7Agelf21 Uk6PsLWrzOihKv01zIG/OwfookI9VAVSXfOUf/TEGlRUh5JYGyF0OG+lk9rNa8sClNMM O8eMoJCtRLHWAtJ9yG5cVGyAOyqGr8zrGj5x2QkK4kcKeQy4/rf+PtoD585kaM/gRc2K TGn8j14HtUxE1ZrUokVQMaDWRLhvKZIZqHm5ongKheFlX85NY9Dk6Isi6Mz0c6s/abik ZyUg== X-Gm-Message-State: AFq9FYJzi3+i0LjrmFj3o6IhRk1dkLuCghvPltzXedM7d0udNaBj1lBU 1YStxIQgAgVzm+YxwQpPMiIDqupbgzzzO8C+C8H97P33SWlCeJ9Nw6TbjT5WRpC+WlWHeImUvMZ LeQRd X-Gm-Gg: AYBFou0SfrhROrW9Dws537CZFCwAEhx8fsK93Y2zbB6DBdGsudBVOBmDnWuGvnnmVpz SqL+aJPKe/qHzkkJ3r+8w/mFQhuoGwQa7YwZJsLEXAAn9X7+QGTAXi3U3iZRTF/Z4VFhyikJOh2 dYz5LkYNOvJu1g1M1sbHr7w3V1xpwAPzrvEqdYrbMkf8dPPuAWFNKNGicsJLeRgTgF6BE79a/rY tulsGGDX6YCOjf2ygTUDVRc/hamHj55JjeMu2KEW/uXfgL2uW5Q2gyOq2FVlSwN3mRF66pWpIn7 TrGBl0Uo1nj6to2v9HjlwYiR+U+sXDJei7PJxCRThc8/dmf7ytpJKCkE8Sm5vthnrcTg8G+J0OI uD1rkkXzjzJy+RRTv2DB4MPV4V4c6UDvJmB79J39pr6xKsTQFo2y15seRTEWtRTitdHyLaFp5MV L5UNhr7Ckfd6DhMtkw9G7GnSIAYXkc6WaY+fjqP62VIqpijl1xnHVYxXJuLh2G0CPyPDF73L1UT XexD0lhrjI61VDwKuOMZCU= X-Received: by 2002:a05:6300:6698:b0:3e1:4fbc:5ce9 with SMTP id adf61e73a8af0-3e164f32a4emr6971521637.20.1791840423279; Mon, 12 Oct 2026 14:27:03 -0700 (PDT) Received: from localhost ([2a03:2880:2ff:58::]) by smtp.gmail.com with ESMTPSA id 41be03b00d2f7-cd3d9e53f8bsm4705338a12.24.2026.10.12.14.27.02 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 12 Oct 2026 14:27:02 -0700 (PDT) Date: Mon, 12 Oct 2026 14:27:01 -0700 From: Joe Damato To: netdev@vger.kernel.org, Michael Chan , Pavan Chebbi , Andrew Lunn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni Cc: edumazet@google.com, horms@kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH net-next v2 2/2] bnxt_en: Pad short SW USO segments to BNXT_MIN_PKT_SIZE Message-ID: Mail-Followup-To: Joe Damato , netdev@vger.kernel.org, Michael Chan , Pavan Chebbi , Andrew Lunn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , edumazet@google.com, horms@kernel.org, linux-kernel@vger.kernel.org References: <20261009215426.2377946-1-joe@dama.to> <20261009215426.2377946-3-joe@dama.to> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20261009215426.2377946-3-joe@dama.to> On Fri, Oct 09, 2026 at 02:54:24PM -0700, Joe Damato wrote: > Each SW USO segment is hdr_len + seg_payload bytes. With IPv4, hdr_len > is 42 bytes, so a segment carrying less than 10 bytes of UDP payload is > sent shorter than BNXT_MIN_PKT_SIZE. This happens with a short last > segment (e.g. gso_size 1400 and 1405 bytes of payload) or with a > gso_size below 10 bytes. [...] > diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_gso.c b/drivers/net/ethernet/broadcom/bnxt/bnxt_gso.c > index ef04c9d08066..80d5c4f963a9 100644 > --- a/drivers/net/ethernet/broadcom/bnxt/bnxt_gso.c > +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_gso.c > @@ -82,11 +82,19 @@ int bnxt_sw_udp_gso_xmit(struct bnxt *bp, struct bnxt_tx_ring_info *txr, > if (unlikely(num_segs <= 1)) > goto drop; > > + /* bnxt_features_check() makes the stack segment these, but paths > + * that skip validate_xmit_skb() (e.g. generic XDP_TX of a GRO'd > + * skb) can still get here. Padding every segment would need more > + * BDs than bds_needed reserves below, so drop instead. > + */ > + if (unlikely(bnxt_sw_gso_pad_len(hdr_len, mss))) > + goto drop; > + I could be wrong, but I think if [1] is applied this drop can go away (?) [1]: https://lore.kernel.org/netdev/20260928223648.2739371-6-kuba@kernel.org/