From patchwork Tue Nov 29 16:06:11 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Li Zetao X-Patchwork-Id: 13058718 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 947E6C4167B for ; Tue, 29 Nov 2022 15:18:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235869AbiK2PS5 (ORCPT ); Tue, 29 Nov 2022 10:18:57 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45718 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235705AbiK2PSY (ORCPT ); Tue, 29 Nov 2022 10:18:24 -0500 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 24A2E2EF4F; Tue, 29 Nov 2022 07:18:22 -0800 (PST) Received: from kwepemi500012.china.huawei.com (unknown [172.30.72.54]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4NM5Yb6d5xzmWHl; Tue, 29 Nov 2022 23:17:39 +0800 (CST) Received: from huawei.com (10.67.175.21) by kwepemi500012.china.huawei.com (7.221.188.12) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Tue, 29 Nov 2022 23:18:18 +0800 From: Li Zetao To: CC: , , , , , , , , , , , , , , , , , , , , , , , , , , , , , Subject: [PATCH v2 1/5] 9p: Fix probe failed when modprobe 9pnet_virtio Date: Wed, 30 Nov 2022 00:06:11 +0800 Message-ID: <20221129160615.3343036-2-lizetao1@huawei.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20221129160615.3343036-1-lizetao1@huawei.com> References: <20221128021005.232105-1-lizetao1@huawei.com> <20221129160615.3343036-1-lizetao1@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.67.175.21] X-ClientProxiedBy: dggems703-chm.china.huawei.com (10.3.19.180) To kwepemi500012.china.huawei.com (7.221.188.12) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org When doing the following test steps, an error was found: step 1: modprobe 9pnet_virtio succeeded # modprobe 9pnet_virtio <-- OK step 2: fault injection in sysfs_create_file() # modprobe -r 9pnet_virtio <-- OK # ... FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 0 CPU: 0 PID: 3790 Comm: modprobe Tainted: G W 6.1.0-rc6-00285-g6a1e40c4b995-dirty #108 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) Call Trace: ... should_failslab+0xa/0x20 ... sysfs_create_file_ns+0x130/0x1d0 p9_virtio_probe+0x662/0xb30 [9pnet_virtio] virtio_dev_probe+0x608/0xae0 ... 9pnet_virtio: probe of virtio3 failed with error -12 step 3: modprobe 9pnet_virtio failed # modprobe 9pnet_virtio <-- failed 9pnet_virtio: probe of virtio3 failed with error -2 The root cause of the problem is that the virtqueues are not stopped on the error handling path when sysfs_create_file() fails in p9_virtio_probe(), resulting in an error "-ENOENT" returned in the next modprobe call in setup_vq(). virtio_pci_modern_device uses virtqueues to send or receive message, and "queue_enable" records whether the queues are available. In vp_modern_find_vqs(), all queues will be selected and activated, but once queues are enabled there is no way to go back except reset. Fix it by reset virtio device on error handling path. After virtio_find_single_vq() succeeded, all virtqueues should be stopped on error handling path. Fixes: ea52bf8eda98 ("9p/trans_virtio: reset virtio device on remove") Signed-off-by: Li Zetao Reviewed-by: Christian Schoenebeck --- v1 -> v2: modify the description error of the test case in step 3 and modify the fixes tag information. net/9p/trans_virtio.c | 1 + 1 file changed, 1 insertion(+) diff --git a/net/9p/trans_virtio.c b/net/9p/trans_virtio.c index e757f0601304..39933187284b 100644 --- a/net/9p/trans_virtio.c +++ b/net/9p/trans_virtio.c @@ -668,6 +668,7 @@ static int p9_virtio_probe(struct virtio_device *vdev) out_free_tag: kfree(tag); out_free_vq: + virtio_reset_device(vdev); vdev->config->del_vqs(vdev); out_free_chan: kfree(chan);