From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 7DF673F23A4; Wed, 20 May 2026 17:49:47 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779299388; cv=none; b=I6aWTzyqS/OLsFuw89zFeG7Fvhwlfa7Z2ho/WRzpBgY+LgqtAHZqgW/haZFSluG9tfgwlxLzheJCZ+w7NdIKOiVbZ00J9TpujuLJswf5Uy20xGBl8zVlfJ6cqr8nfFNZNr4jWkALPE2xQlmK0DSsunJr4yf7o3AoDyOt6FmINTM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779299388; c=relaxed/simple; bh=N9NW18o1MwtLyMGvudtOL/P+LAzX2DCXIgdExzG6ZXE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=GjA6B44qQ7Tifjoi9XXVb/x7cu6lJDZuwQXUMfyP83VVWs7Sc31WxMwTgV4umDn+if0C1LmQzXO6C0s6KPxP+zZzo8PtExdhhDDzhh76BH+l2rt7JMsGP6oqyoBuU8svMdJCV8i6b8LXxeVWKO5wBuFX3lWw0bQv335lpBNGDA0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=RzGXl5Yg; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="RzGXl5Yg" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E2AAC1F000E9; Wed, 20 May 2026 17:49:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1779299387; bh=agjgR+vvzUNbZBXPTvvpT1AgFU0HL7w+r1WRkbd12do=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=RzGXl5Yg2hx1W0wWSSAoJiomR0g7RFkenjxvsl5QO+0T02sHpN4eDI2Dft3L/Bt35 j/vSTJiEDx8uwv9gqBhahtzmaWJsaIkCBhKHVMjUaVfZ4jhm7UmRljHnsnADTNUskt /EwU3hdvQ0aDSs8ksRONOBC+umyUuecUVHMjGePc= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Brett Creeley , "Michael S. Tsirkin" , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.18 711/957] virtio_net: sync rss_trailer.max_tx_vq on queue_pairs change via VQ_PAIRS_SET Date: Wed, 20 May 2026 18:19:54 +0200 Message-ID: <20260520162149.964504635@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260520162134.554764788@linuxfoundation.org> References: <20260520162134.554764788@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Brett Creeley [ Upstream commit 3bc06da858ef17cfe94b49efc0d9713727012835 ] When netif_is_rxfh_configured() is true (i.e., the user has explicitly configured the RSS indirection table), virtnet_set_queues() skips the RSS update path and falls through to the VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET command to change the number of queue pairs. However, it does not update vi->rss_trailer.max_tx_vq to reflect the new queue_pairs value. This causes a mismatch between vi->curr_queue_pairs and vi->rss_trailer.max_tx_vq. Any subsequent RSS reconfiguration (e.g., via ethtool -X) calls virtnet_commit_rss_command(), which sends the stale max_tx_vq to the device, silently reverting the queue count. Reproduction: 1. User configured RSS ethtool -X eth0 equal 8 2. VQ_PAIRS_SET path; max_tx_vq stays 16 ethtool -L eth0 combined 12 3. RSS commit uses max_tx_vq=16 instead of 12 ethtool -X eth0 equal 4 Fix this by updating vi->rss_trailer.max_tx_vq after a successful VQ_PAIRS_SET command when RSS is enabled, keeping it in sync with curr_queue_pairs. Fixes: 50bfcaedd78e ("virtio_net: Update rss when set queue") Signed-off-by: Brett Creeley Acked-by: Michael S. Tsirkin Link: https://patch.msgid.link/20260416212121.29073-1-brett.creeley@amd.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/net/virtio_net.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 0cfe7ab59412c..aed65dbf3fca0 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -3828,6 +3828,12 @@ static int virtnet_set_queues(struct virtnet_info *vi, u16 queue_pairs) queue_pairs); return -EINVAL; } + + /* Keep max_tx_vq in sync so that a later RSS command does not + * revert queue_pairs to a stale value. + */ + if (vi->has_rss) + vi->rss_trailer.max_tx_vq = cpu_to_le16(queue_pairs); succ: vi->curr_queue_pairs = queue_pairs; if (dev->flags & IFF_UP) { -- 2.53.0