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 4B086611E; Tue, 5 Dec 2023 03:41:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="FEET2EzM" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BCE7CC433C8; Tue, 5 Dec 2023 03:41:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1701747681; bh=qSBGk3ze9wlxeRTxXTz2c0VrSwLYNAw9rE8hkjH3gJc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=FEET2EzMPQkGHKWdfa96mRmrFYMOylifvxrrYeFY+8B2D6CST18z0AOcXu0IJQ0NL tUfBhzv1QOICGX6BDe6J/oMVGbXyjNMRlEqTZh+wwGyw8kN7KRaDe4vMfyIiUES5d1 /DdmST7eprZ2ymqxVFn4eKaYwmYmIT6wjp3KVPTE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Dexuan Cui , Haiyang Zhang , Wojciech Drewek , Simon Horman , Paolo Abeni , Sasha Levin Subject: [PATCH 5.15 28/67] hv_netvsc: fix race of netvsc and VF register_netdevice Date: Tue, 5 Dec 2023 12:17:13 +0900 Message-ID: <20231205031521.426283901@linuxfoundation.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20231205031519.853779502@linuxfoundation.org> References: <20231205031519.853779502@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 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Haiyang Zhang [ Upstream commit d30fb712e52964f2cf9a9c14cf67078394044837 ] The rtnl lock also needs to be held before rndis_filter_device_add() which advertises nvsp_2_vsc_capability / sriov bit, and triggers VF NIC offering and registering. If VF NIC finished register_netdev() earlier it may cause name based config failure. To fix this issue, move the call to rtnl_lock() before rndis_filter_device_add(), so VF will be registered later than netvsc / synthetic NIC, and gets a name numbered (ethX) after netvsc. Cc: stable@vger.kernel.org Fixes: e04e7a7bbd4b ("hv_netvsc: Fix a deadlock by getting rtnl lock earlier in netvsc_probe()") Reported-by: Dexuan Cui Signed-off-by: Haiyang Zhang Reviewed-by: Wojciech Drewek Reviewed-by: Simon Horman Reviewed-by: Dexuan Cui Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin --- drivers/net/hyperv/netvsc_drv.c | 25 +++++++++++++++---------- 1 file changed, 15 insertions(+), 10 deletions(-) diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c index ce1b299c89f53..c3a8ac244a08e 100644 --- a/drivers/net/hyperv/netvsc_drv.c +++ b/drivers/net/hyperv/netvsc_drv.c @@ -2563,15 +2563,6 @@ static int netvsc_probe(struct hv_device *dev, goto devinfo_failed; } - nvdev = rndis_filter_device_add(dev, device_info); - if (IS_ERR(nvdev)) { - ret = PTR_ERR(nvdev); - netdev_err(net, "unable to add netvsc device (ret %d)\n", ret); - goto rndis_failed; - } - - memcpy(net->dev_addr, device_info->mac_adr, ETH_ALEN); - /* We must get rtnl lock before scheduling nvdev->subchan_work, * otherwise netvsc_subchan_work() can get rtnl lock first and wait * all subchannels to show up, but that may not happen because @@ -2579,9 +2570,23 @@ static int netvsc_probe(struct hv_device *dev, * -> ... -> device_add() -> ... -> __device_attach() can't get * the device lock, so all the subchannels can't be processed -- * finally netvsc_subchan_work() hangs forever. + * + * The rtnl lock also needs to be held before rndis_filter_device_add() + * which advertises nvsp_2_vsc_capability / sriov bit, and triggers + * VF NIC offering and registering. If VF NIC finished register_netdev() + * earlier it may cause name based config failure. */ rtnl_lock(); + nvdev = rndis_filter_device_add(dev, device_info); + if (IS_ERR(nvdev)) { + ret = PTR_ERR(nvdev); + netdev_err(net, "unable to add netvsc device (ret %d)\n", ret); + goto rndis_failed; + } + + memcpy(net->dev_addr, device_info->mac_adr, ETH_ALEN); + if (nvdev->num_chn > 1) schedule_work(&nvdev->subchan_work); @@ -2615,9 +2620,9 @@ static int netvsc_probe(struct hv_device *dev, return 0; register_failed: - rtnl_unlock(); rndis_filter_device_remove(dev, nvdev); rndis_failed: + rtnl_unlock(); netvsc_devinfo_put(device_info); devinfo_failed: free_percpu(net_device_ctx->vf_stats); -- 2.42.0