From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 060B61A6192; Tue, 30 Jul 2024 16:38:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722357505; cv=none; b=buNlmM/yGC9sJpMfrGL8RbnLx5G79g8d0qE3XAbLBeOOJxneJxFs+MJ1061p0/wuDnkoQvCuLhYfipAADs7euHGWm+B+QFMD+XwHDEKKmc3uRUwPRAneQfYrLEwUAG6O2/F0Ulb70UuH2rOtYVbzLHmcDp5zYpOY1F4qWvdDcMQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722357505; c=relaxed/simple; bh=eUTh0t10MyrZNIQJKO8l64Vl34m9Gd7BXQKmZmGcBFE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=aw0sUJk+G85jUIjqzEiUgmvHy2R0KlNxQuZKN1CNj68qJZJcU7X7mVHCb4UZ5LF6eoMdVp1wCILQgnUfRnEq54eGT/mPEH7KCXchFwKKhC+3m+gXB1Fd5+CmFMwHH0TwcrPWOh6Cu3bIP1/WN7rrNFVy/lG4s5sopbRIsr0bUn4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=NO0/oRoe; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="NO0/oRoe" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6A512C32782; Tue, 30 Jul 2024 16:38:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1722357504; bh=eUTh0t10MyrZNIQJKO8l64Vl34m9Gd7BXQKmZmGcBFE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=NO0/oRoe00syV3kVPo71seHhFqlHgsdt+D7Qde06uAHagc3UuzPc1FRMWmBKLN8Dg GZFoXBQ793rP+yYGXwmxqeNw0fvRvvnj+TnTh4o5VMPbC3KEsIfp1g5ZWkmogvYYzL 14aHf62Mvs/X7Z49TyMcHJv3p8oWSpIwKuNve+KA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jakub Kicinski , Breno Leitao , "Michael S. Tsirkin" , Jason Wang , Heng Qi , Sasha Levin Subject: [PATCH 6.10 260/809] virtio_net: Fix napi_skb_cache_put warning Date: Tue, 30 Jul 2024 17:42:16 +0200 Message-ID: <20240730151734.863466508@linuxfoundation.org> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20240730151724.637682316@linuxfoundation.org> References: <20240730151724.637682316@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Breno Leitao [ Upstream commit f8321fa75102246d7415a6af441872f6637c93ab ] After the commit bdacf3e34945 ("net: Use nested-BH locking for napi_alloc_cache.") was merged, the following warning began to appear: WARNING: CPU: 5 PID: 1 at net/core/skbuff.c:1451 napi_skb_cache_put+0x82/0x4b0 __warn+0x12f/0x340 napi_skb_cache_put+0x82/0x4b0 napi_skb_cache_put+0x82/0x4b0 report_bug+0x165/0x370 handle_bug+0x3d/0x80 exc_invalid_op+0x1a/0x50 asm_exc_invalid_op+0x1a/0x20 __free_old_xmit+0x1c8/0x510 napi_skb_cache_put+0x82/0x4b0 __free_old_xmit+0x1c8/0x510 __free_old_xmit+0x1c8/0x510 __pfx___free_old_xmit+0x10/0x10 The issue arises because virtio is assuming it's running in NAPI context even when it's not, such as in the netpoll case. To resolve this, modify virtnet_poll_tx() to only set NAPI when budget is available. Same for virtnet_poll_cleantx(), which always assumed that it was in a NAPI context. Fixes: df133f3f9625 ("virtio_net: bulk free tx skbs") Suggested-by: Jakub Kicinski Signed-off-by: Breno Leitao Reviewed-by: Jakub Kicinski Acked-by: Michael S. Tsirkin Acked-by: Jason Wang Reviewed-by: Heng Qi Link: https://patch.msgid.link/20240712115325.54175-1-leitao@debian.org Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/net/virtio_net.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index b1f8b720733e5..cd254a1fd88ec 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -2341,7 +2341,7 @@ static int virtnet_receive(struct receive_queue *rq, int budget, return packets; } -static void virtnet_poll_cleantx(struct receive_queue *rq) +static void virtnet_poll_cleantx(struct receive_queue *rq, int budget) { struct virtnet_info *vi = rq->vq->vdev->priv; unsigned int index = vq2rxq(rq->vq); @@ -2359,7 +2359,7 @@ static void virtnet_poll_cleantx(struct receive_queue *rq) do { virtqueue_disable_cb(sq->vq); - free_old_xmit(sq, txq, true); + free_old_xmit(sq, txq, !!budget); } while (unlikely(!virtqueue_enable_cb_delayed(sq->vq))); if (sq->vq->num_free >= 2 + MAX_SKB_FRAGS) { @@ -2403,7 +2403,7 @@ static int virtnet_poll(struct napi_struct *napi, int budget) unsigned int xdp_xmit = 0; bool napi_complete; - virtnet_poll_cleantx(rq); + virtnet_poll_cleantx(rq, budget); received = virtnet_receive(rq, budget, &xdp_xmit); rq->packets_in_napi += received; @@ -2518,7 +2518,7 @@ static int virtnet_poll_tx(struct napi_struct *napi, int budget) txq = netdev_get_tx_queue(vi->dev, index); __netif_tx_lock(txq, raw_smp_processor_id()); virtqueue_disable_cb(sq->vq); - free_old_xmit(sq, txq, true); + free_old_xmit(sq, txq, !!budget); if (sq->vq->num_free >= 2 + MAX_SKB_FRAGS) { if (netif_tx_queue_stopped(txq)) { -- 2.43.0