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 75B3217AE00; Tue, 10 Sep 2024 10:00:07 +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=1725962407; cv=none; b=pSS+ACtgQD+g0suKgByvKi4mLKaSN0JFfr9MG8ntJDoDdX5Ut9MIoqRQ1aoxqFDa5cMoWP5+PmQ+zZN7fYfVXyxqO4nfMFl1yIn3BYDUfzqH9N1gWe6ZlTqWWIk8um2gRaOaJreRKNyre3xdkwGPJ2CRHCVKYWmvR2cmPp8v6TE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725962407; c=relaxed/simple; bh=TpdSuptpqqDTm4klHbghUFTJpZ5GtUqmZz2xYCQVOBc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=LZtTi8sczSCMygEA0brjCHPnGB3uHa1BQXg0J3Zb4LwG4JojqWVslzXGX9eRVwr4ViKNeW2FmrTjgZTasQMC4Uo4B1l/7pB+Iz/lQWs3QrLFtX/WEDdlkk4LB8N/ht4yprov+QqtlmgHHC+Zl8DoVt1UFDAJgU8fzBoBsLGyXso= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=symlzPOh; 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="symlzPOh" Received: by smtp.kernel.org (Postfix) with ESMTPSA id EFC54C4CEC3; Tue, 10 Sep 2024 10:00:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1725962407; bh=TpdSuptpqqDTm4klHbghUFTJpZ5GtUqmZz2xYCQVOBc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=symlzPOhvt5oZz3x/+H112UzInuCo4g+b7tZIN0aU6QQ3XEyDXRC0BJ6IFfnrVpaO YrCaTrGgO7tYvFI3DcbmGlaR67vRuDibsSWXDt2bfelmqgBHFbfomkDk4+nZtaOamy ChUjNgPG2WdhdhId6gqDvOqapm3GO2eXbLaf/TwI= 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 , Shivani Agarwal Subject: [PATCH 5.4 023/121] virtio_net: Fix napi_skb_cache_put warning Date: Tue, 10 Sep 2024 11:31:38 +0200 Message-ID: <20240910092546.813146598@linuxfoundation.org> X-Mailer: git-send-email 2.46.0 In-Reply-To: <20240910092545.737864202@linuxfoundation.org> References: <20240910092545.737864202@linuxfoundation.org> User-Agent: quilt/0.67 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 5.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Breno Leitao commit f8321fa75102246d7415a6af441872f6637c93ab upstream. 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 [Shivani: Modified to apply on v4.19.y-v5.10.y] Signed-off-by: Shivani Agarwal Signed-off-by: Greg Kroah-Hartman --- drivers/net/virtio_net.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -1479,7 +1479,7 @@ static bool is_xdp_raw_buffer_queue(stru return false; } -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); @@ -1490,7 +1490,7 @@ static void virtnet_poll_cleantx(struct return; if (__netif_tx_trylock(txq)) { - free_old_xmit_skbs(sq, true); + free_old_xmit_skbs(sq, !!budget); __netif_tx_unlock(txq); } @@ -1507,7 +1507,7 @@ static int virtnet_poll(struct napi_stru unsigned int received; unsigned int xdp_xmit = 0; - virtnet_poll_cleantx(rq); + virtnet_poll_cleantx(rq, budget); received = virtnet_receive(rq, budget, &xdp_xmit); @@ -1580,7 +1580,7 @@ static int virtnet_poll_tx(struct napi_s txq = netdev_get_tx_queue(vi->dev, index); __netif_tx_lock(txq, raw_smp_processor_id()); virtqueue_disable_cb(sq->vq); - free_old_xmit_skbs(sq, true); + free_old_xmit_skbs(sq, !!budget); opaque = virtqueue_enable_cb_prepare(sq->vq);