From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 950FA302756 for ; Sat, 7 Feb 2026 10:37:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770460620; cv=none; b=k5ZS7xXvHaJa1msvy94IsOxMVNfsEkUUt37qyu+znptgy1xiVn4PCCn5nj6DyJFvhZu3FFZiLwFdMUfqep0VJzhFTS5fQ7R4m92LbOcrct1oB2GniBzV/5S6SOFdYCJhud8TZgDrcry3U8l8v9UIVXjWWUnfywUR5b5YaFZZXv4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770460620; c=relaxed/simple; bh=LSToBen3PC7STn5LIO5y4sRfmIQC6eXFBNpCr3/T+cE=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=Z3xONHlZh87QId6Ak9TH7wP3ZU71VmCyJwXSxK6HPzq8oOKFPeBpiy3rOGRmVGW1xHMKVrUoyqb0FkEexx0EE5Ji13fA3tw7u81XGDj29k72UivOKOWqYSgIRHav+di00BZnhRqr8BzYeI3GTIsFL9K9f6agm1Wf6Y+4Nxe55zY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=Lnk4xgc4; dkim=pass (2048-bit key) header.d=redhat.com header.i=@redhat.com header.b=LWiB0+ok; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="Lnk4xgc4"; dkim=pass (2048-bit key) header.d=redhat.com header.i=@redhat.com header.b="LWiB0+ok" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1770460619; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=kh3D9klgXXKO9Bcq7zAYbqELTISjbIQTe+oHD7vW69Q=; b=Lnk4xgc4hE3Od5d2fdV/TXSCL3I7Uo8CgsKTDtjjfLm+QCYihWvH0bW2s8hiH4kJkB0K5P wXYsmZxKux+w9p6fEAQ1bo8yhHIbNPtkp+crx+LUzgOqRBJiXsTwcWAj2e9XLaw3b+Zo+j Be5qf/g30oFNTm8US5rriNbb8H/bUmo= Received: from mail-wm1-f69.google.com (mail-wm1-f69.google.com [209.85.128.69]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-478-bQw8gWoKM5K_vo-oQo7-2g-1; Sat, 07 Feb 2026 05:36:58 -0500 X-MC-Unique: bQw8gWoKM5K_vo-oQo7-2g-1 X-Mimecast-MFC-AGG-ID: bQw8gWoKM5K_vo-oQo7-2g_1770460617 Received: by mail-wm1-f69.google.com with SMTP id 5b1f17b1804b1-48070c21420so29007735e9.0 for ; Sat, 07 Feb 2026 02:36:58 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=google; t=1770460617; x=1771065417; darn=vger.kernel.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=kh3D9klgXXKO9Bcq7zAYbqELTISjbIQTe+oHD7vW69Q=; b=LWiB0+ok4+TyBTwB70/R9IjuhjysDBkZFBr2UmbhpX1uOvT86tNFDtVPjbUDh7Ynb4 jRtOwmG0ycxr7ZJ3y44I/cvP1sVltEtmQpP+cTBkpZ3Wq1UK43f+ViMGvHiZb+udZAWy GGm4LSOJ/l1C/GZurflG1kG9ttbkHysh0A3BZNTYSCHcB8eqzfmrXLnHpGGZOP+MpNBN hpVaACXSZopHEfr/aFKOZ8uvdySA3Pc0o5yTckB866CuKhAxCQjKRVYS8Cksb71sA1eP +YI7SzPpsw3B7ZvTz5GcgS4jya9k969BEYkGLdEjxZOk6lfX3mn89clvXMtw8ysHFy/G 0FWg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1770460617; x=1771065417; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-gg:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=kh3D9klgXXKO9Bcq7zAYbqELTISjbIQTe+oHD7vW69Q=; b=gnGSSkg7Ip0ZflG0YLZjN0LbDDzL49ck3ohHXl5T7WufP5YOLzH59kRDaOvwcePf+d P1/XsyVQ4CFkxOplDpz7IPo6y/VnwDFefS3vjlP+tVMKSW6+DQDyhmsLK7DS3CQuFNZJ GQdA3NWSeXyeLrpJY1wOAukEavmvdp+plC1q335sC/InDoZYeWqLreU1yiWvvW9+ziXP yHDz/VhqMEa1ekxuWRcWGifTvaca+vgZSyWYDW+TTDmrp7JYUbqGjhdrLQ9tn0Ol4ZfW L3Wvkivhznna8e5Q6gzTDzOzUNe5w9VN2qjmAyk9V+XFEBg24OKp09Nkon3Zx6SIiJGM C8og== X-Forwarded-Encrypted: i=1; AJvYcCWanftlAhAPhSkyqyGz+Xf3bEyHFGYn0oQHJh0aGUAid48YhfKtLyovhV5Z5jyoHwHBaUlgU3g=@vger.kernel.org X-Gm-Message-State: AOJu0YzU+wM3vxZ2CZ6OXo+3hmziNPo8SOzij5fqkfuWmSk2X11Mb49m B4+tjd2ZB8wEvEAciABXLlqRha5toGyJheXeABGEbCcbvocjTCdkagLq1gHJiLZVCnKD+Am1D9l IjhzM9MUtUoi98nPxR2jWzpenm8pwV6sy7ueeuW/KlTmJXE2daw368rGjuw== X-Gm-Gg: AZuq6aIG5+ug0bYPNcpmAHWc82I+IUKd1Josrap0+iKu/j1EpRFHqMYy3vKmEYYeRsv rS8+c1P+vf5dBVdVNTxmZkec+3h7vl3NtHPjsRGy4Plo09OaKTgmvXmKHHiuku7E4ogrB2lsYP/ 9/3+ubQeQ7nO9WjPUhsxAgccejo0OM8+32usCnal0kaU4m/hJyHiGOdWozFic1x8IrLRTePhOjz fUWlr71cuBOtszrjloKHktXZ69XRXsRnFNWWaUOEuGBRsMBq+QO9OMzmwKRl7WL41qUaetaFrDb 7gpULMm5cVSORYsdtNpywwLEqC+Kuq/2/jOxB766bWUVAu1zDk9Fpv2RdFqg89zjvhPYFMG/1Ym vk1HAT9egT0vk9XFjpI8lBKFb1ncsxPzPIw== X-Received: by 2002:a05:600c:810c:b0:47e:e59c:67c5 with SMTP id 5b1f17b1804b1-483203ab857mr91768495e9.8.1770460617158; Sat, 07 Feb 2026 02:36:57 -0800 (PST) X-Received: by 2002:a05:600c:810c:b0:47e:e59c:67c5 with SMTP id 5b1f17b1804b1-483203ab857mr91768265e9.8.1770460616804; Sat, 07 Feb 2026 02:36:56 -0800 (PST) Received: from redhat.com (IGLD-80-230-34-155.inter.net.il. [80.230.34.155]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-48320719bf4sm107581565e9.10.2026.02.07.02.36.55 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 07 Feb 2026 02:36:56 -0800 (PST) Date: Sat, 7 Feb 2026 05:36:53 -0500 From: "Michael S. Tsirkin" To: Jakub Kicinski Cc: Srujana Challa , netdev@vger.kernel.org, virtualization@lists.linux.dev, pabeni@redhat.com, jasowang@redhat.com, xuanzhuo@linux.alibaba.com, eperezma@redhat.com, davem@davemloft.net, edumazet@google.com, ndabilpuram@marvell.com, kshankar@marvell.com Subject: Re: [PATCH v2 net-next] virtio_net: Improve RSS key size validation and use NETDEV_RSS_KEY_LEN Message-ID: <20260207052531-mutt-send-email-mst@kernel.org> References: <20260206120154.2548079-1-schalla@marvell.com> <20260206191308.7fdbfef4@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=us-ascii Content-Disposition: inline In-Reply-To: <20260206191308.7fdbfef4@kernel.org> On Fri, Feb 06, 2026 at 07:13:08PM -0800, Jakub Kicinski wrote: > On Fri, 6 Feb 2026 17:31:54 +0530 Srujana Challa wrote: > > Replace hardcoded RSS max key size limit with NETDEV_RSS_KEY_LEN to > > align with kernel's standard RSS key length. Add validation for RSS > > key size against spec minimum (40 bytes) and driver maximum. When > > validation fails, gracefully disable RSS features and continue > > initialization rather than failing completely. > > Hm, FWIW clang says: > > drivers/net/virtio_net.c:6841:31: warning: result of comparison of constant 256 with expression of type 'u8' (aka 'unsigned char') is always false [-Wtautological-constant-out-of-range-compare] > 6841 | } else if (vi->rss_key_size > VIRTIO_NET_RSS_MAX_KEY_SIZE) { > | ~~~~~~~~~~~~~~~~ ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > Which is kinda annoying because the value was increased in net-next. > If Machael wants this backported then we need to keep the check > and follow up in net-next? We could try to cast the u32 away but > that feels dirty.. for net next we will presumably replace with BUILD_BUG_ON(type_max(vi->rss_key_size) > NETDEV_RSS_KEY_LEN) and I think we should get rid of VIRTIO_NET_RSS_MAX_KEY_SIZE while we are at it. -- MST