From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0CC47C433E1 for ; Thu, 28 May 2020 12:04:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DDA6E21655 for ; Thu, 28 May 2020 12:04:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1590667458; bh=lPViImP71+4x4gMwxZj/6MRQ7z+RsErsVnyCiG+Cvl0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=1bcUKVHsbb95nqiUnyAch6HlM8Vxu5FtHRuYDXb4Cp8obrprfOzYndAuqsHL700fC 8TPk+GNTLBrIFhWp+WgnVXDMBhnWzEpu1GW6Np/6Gn/zwMrhqISmBKva7rOPAUOtzZ VPFCtjH7QHLm0RKxSTsmg/WAVjbcAlYovX9KsO/s= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389301AbgE1MEO (ORCPT ); Thu, 28 May 2020 08:04:14 -0400 Received: from mail.kernel.org ([198.145.29.99]:49750 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388548AbgE1L5Q (ORCPT ); Thu, 28 May 2020 07:57:16 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 39AED21582; Thu, 28 May 2020 11:57:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1590667036; bh=lPViImP71+4x4gMwxZj/6MRQ7z+RsErsVnyCiG+Cvl0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=aFA3rmBGToL7EPSUZgdy7flFd5UMVq41gMQrZETXvC36Bi5DRuS8ziUeCQBMHy9bb 4Iccfvxt3PcwpCZ/jhD3ow5pW2KLFb0w0g6niDKoi2xZXXi1kNTBnAe/CpCUuidPY7 sFSl20DePbY+mdl9MYilgDIBQxc2bDI0nHi66bGc= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Moshe Shemesh , Eran Ben Elisha , Saeed Mahameed , Sasha Levin , netdev@vger.kernel.org, linux-rdma@vger.kernel.org Subject: [PATCH AUTOSEL 5.4 19/26] net/mlx5: Add command entry handling completion Date: Thu, 28 May 2020 07:56:47 -0400 Message-Id: <20200528115654.1406165-19-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200528115654.1406165-1-sashal@kernel.org> References: <20200528115654.1406165-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Moshe Shemesh [ Upstream commit 17d00e839d3b592da9659c1977d45f85b77f986a ] When FW response to commands is very slow and all command entries in use are waiting for completion we can have a race where commands can get timeout before they get out of the queue and handled. Timeout completion on uninitialized command will cause releasing command's buffers before accessing it for initialization and then we will get NULL pointer exception while trying access it. It may also cause releasing buffers of another command since we may have timeout completion before even allocating entry index for this command. Add entry handling completion to avoid this race. Fixes: e126ba97dba9 ("mlx5: Add driver for Mellanox Connect-IB adapters") Signed-off-by: Moshe Shemesh Signed-off-by: Eran Ben Elisha Signed-off-by: Saeed Mahameed Signed-off-by: Sasha Levin --- drivers/net/ethernet/mellanox/mlx5/core/cmd.c | 14 ++++++++++++++ include/linux/mlx5/driver.h | 1 + 2 files changed, 15 insertions(+) diff --git a/drivers/net/ethernet/mellanox/mlx5/core/cmd.c b/drivers/net/ethernet/mellanox/mlx5/core/cmd.c index 08048a2d7259..b6a3370068f1 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/cmd.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/cmd.c @@ -861,6 +861,7 @@ static void cmd_work_handler(struct work_struct *work) int alloc_ret; int cmd_mode; + complete(&ent->handling); sem = ent->page_queue ? &cmd->pages_sem : &cmd->sem; down(sem); if (!ent->page_queue) { @@ -978,6 +979,11 @@ static int wait_func(struct mlx5_core_dev *dev, struct mlx5_cmd_work_ent *ent) struct mlx5_cmd *cmd = &dev->cmd; int err; + if (!wait_for_completion_timeout(&ent->handling, timeout) && + cancel_work_sync(&ent->work)) { + ent->ret = -ECANCELED; + goto out_err; + } if (cmd->mode == CMD_MODE_POLLING || ent->polling) { wait_for_completion(&ent->done); } else if (!wait_for_completion_timeout(&ent->done, timeout)) { @@ -985,12 +991,17 @@ static int wait_func(struct mlx5_core_dev *dev, struct mlx5_cmd_work_ent *ent) mlx5_cmd_comp_handler(dev, 1UL << ent->idx, true); } +out_err: err = ent->ret; if (err == -ETIMEDOUT) { mlx5_core_warn(dev, "%s(0x%x) timeout. Will cause a leak of a command resource\n", mlx5_command_str(msg_to_opcode(ent->in)), msg_to_opcode(ent->in)); + } else if (err == -ECANCELED) { + mlx5_core_warn(dev, "%s(0x%x) canceled on out of queue timeout.\n", + mlx5_command_str(msg_to_opcode(ent->in)), + msg_to_opcode(ent->in)); } mlx5_core_dbg(dev, "err %d, delivery status %s(%d)\n", err, deliv_status_to_str(ent->status), ent->status); @@ -1026,6 +1037,7 @@ static int mlx5_cmd_invoke(struct mlx5_core_dev *dev, struct mlx5_cmd_msg *in, ent->token = token; ent->polling = force_polling; + init_completion(&ent->handling); if (!callback) init_completion(&ent->done); @@ -1045,6 +1057,8 @@ static int mlx5_cmd_invoke(struct mlx5_core_dev *dev, struct mlx5_cmd_msg *in, err = wait_func(dev, ent); if (err == -ETIMEDOUT) goto out; + if (err == -ECANCELED) + goto out_free; ds = ent->ts2 - ent->ts1; op = MLX5_GET(mbox_in, in->first.data, opcode); diff --git a/include/linux/mlx5/driver.h b/include/linux/mlx5/driver.h index 3e80f03a387f..897829651204 100644 --- a/include/linux/mlx5/driver.h +++ b/include/linux/mlx5/driver.h @@ -756,6 +756,7 @@ struct mlx5_cmd_work_ent { struct delayed_work cb_timeout_work; void *context; int idx; + struct completion handling; struct completion done; struct mlx5_cmd *cmd; struct work_struct work; -- 2.25.1