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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3E885C4332F for ; Fri, 3 Dec 2021 05:54:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1378539AbhLCF5y (ORCPT ); Fri, 3 Dec 2021 00:57:54 -0500 Received: from smtprelay0250.hostedemail.com ([216.40.44.250]:55412 "EHLO smtprelay.hostedemail.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S231182AbhLCF5x (ORCPT ); Fri, 3 Dec 2021 00:57:53 -0500 Received: from omf18.hostedemail.com (clb03-v110.bra.tucows.net [216.40.38.60]) by smtprelay04.hostedemail.com (Postfix) with ESMTP id C73411812EF2A; Fri, 3 Dec 2021 05:54:27 +0000 (UTC) Received: from [HIDDEN] (Authenticated sender: joe@perches.com) by omf18.hostedemail.com (Postfix) with ESMTPA id 3C21F35; Fri, 3 Dec 2021 05:54:26 +0000 (UTC) Message-ID: Subject: Re: [RFC Patch v2 1/3] i2c debug counters as sysfs attributes From: Joe Perches To: Sui Chen , linux-kernel@vger.kernel.org Cc: openbmc@lists.ozlabs.org, linux-i2c@vger.kernel.org, joel@jms.id.au, andrew@aj.id.au, tali.perry1@gmail.com, benjaminfair@google.com, krellan@google.com Date: Thu, 02 Dec 2021 21:54:25 -0800 In-Reply-To: <20211203023728.3699610-2-suichen@google.com> References: <20211203023728.3699610-1-suichen@google.com> <20211203023728.3699610-2-suichen@google.com> Content-Type: text/plain; charset="ISO-8859-1" User-Agent: Evolution 3.40.4-1ubuntu2 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 3C21F35 X-Stat-Signature: rqema1cduzhupfdpnd4z7soeitwq9m7g X-Rspamd-Server: rspamout04 X-Session-Marker: 6A6F6540706572636865732E636F6D X-Session-ID: U2FsdGVkX18mAWqEgH6LGGdG9zFQcE5JiVDmWP40504= X-HE-Tag: 1638510866-239568 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2021-12-02 at 18:37 -0800, Sui Chen wrote: > This change adds a few example I2C debug counters as sysfs attributes: > - ber_cnt (bus error count) > - nack_cnt (NACK count) > - rec_fail_cnt, rec_succ_cnt (recovery failure/success count) > - timeout_cnt (timeout count) > - i2c_speed (bus frequency) > - tx_complete_cnt (transaction completed, including both as an initiator > and as a target) > > The function i2c_adapter_create_stats_folder creates a stats directory > in the device's sysfs directory to hold the debug counters. The platform > drivers are responsible for instantiating the counters in the stats > directory if applicable. [] > diff --git a/drivers/i2c/i2c-dev.c b/drivers/i2c/i2c-dev.c [] > +void i2c_adapter_create_stats_folder(struct i2c_adapter* adapter) { > + adapter->stats = kzalloc(sizeof(struct i2c_adapter_stats), GFP_KERNEL); unchecked alloc, could fail. > + adapter->stats->kobj = kobject_create_and_add("stats", &adapter->dev.kobj);; > +} > + > +void i2c_adapter_stats_register_counter(struct i2c_adapter* adapter, > + const char* counter_name, void* data_source) { > + int ret; > + if (adapter->stats == NULL) { > + i2c_adapter_create_stats_folder(adapter); > + } So all of these adapter->stats dereferences could oops. > + if (!strcmp(counter_name, "ber_cnt")) { > + adapter->stats->ber_cnt = data_source; > + ret = sysfs_create_file(adapter->stats->kobj, &dev_attr_ber_cnt.attr); > + } else if (!strcmp(counter_name, "nack_cnt")) { > + adapter->stats->nack_cnt = data_source; > + ret = sysfs_create_file(adapter->stats->kobj, &dev_attr_nack_cnt.attr); > + } else if (!strcmp(counter_name, "rec_succ_cnt")) { > + adapter->stats->rec_succ_cnt = data_source; > + ret = sysfs_create_file(adapter->stats->kobj, &dev_attr_rec_succ_cnt.attr); > + } else if (!strcmp(counter_name, "rec_fail_cnt")) { > + adapter->stats->rec_fail_cnt = data_source; > + ret = sysfs_create_file(adapter->stats->kobj, &dev_attr_rec_fail_cnt.attr); > + } else if (!strcmp(counter_name, "timeout_cnt")) { > + adapter->stats->timeout_cnt = data_source; > + ret = sysfs_create_file(adapter->stats->kobj, &dev_attr_timeout_cnt.attr); > + } else if (!strcmp(counter_name, "i2c_speed")) { > + adapter->stats->i2c_speed = data_source; > + ret = sysfs_create_file(adapter->stats->kobj, &dev_attr_i2c_speed.attr); > + } else if (!strcmp(counter_name, "tx_complete_cnt")) { > + adapter->stats->tx_complete_cnt = data_source; > + ret = sysfs_create_file(adapter->stats->kobj, &dev_attr_tx_complete_cnt.attr); > + } and if none of the strcmp comparisons match, ret is uninitialized. > + > + if (ret) { > + printk("Failed to create sysfs file for %s", counter_name); pr_ and should have a terminating newline 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 Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 8DADAC433EF for ; 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Fri, 3 Dec 2021 05:54:26 +0000 (UTC) Message-ID: Subject: Re: [RFC Patch v2 1/3] i2c debug counters as sysfs attributes From: Joe Perches To: Sui Chen , linux-kernel@vger.kernel.org Date: Thu, 02 Dec 2021 21:54:25 -0800 In-Reply-To: <20211203023728.3699610-2-suichen@google.com> References: <20211203023728.3699610-1-suichen@google.com> <20211203023728.3699610-2-suichen@google.com> Content-Type: text/plain; charset="ISO-8859-1" User-Agent: Evolution 3.40.4-1ubuntu2 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 3C21F35 X-Stat-Signature: rqema1cduzhupfdpnd4z7soeitwq9m7g X-Rspamd-Server: rspamout04 X-Session-Marker: 6A6F6540706572636865732E636F6D X-Session-ID: U2FsdGVkX18mAWqEgH6LGGdG9zFQcE5JiVDmWP40504= X-HE-Tag: 1638510866-239568 X-BeenThere: openbmc@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Development list for OpenBMC List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: benjaminfair@google.com, andrew@aj.id.au, openbmc@lists.ozlabs.org, tali.perry1@gmail.com, krellan@google.com, linux-i2c@vger.kernel.org Errors-To: openbmc-bounces+openbmc=archiver.kernel.org@lists.ozlabs.org Sender: "openbmc" On Thu, 2021-12-02 at 18:37 -0800, Sui Chen wrote: > This change adds a few example I2C debug counters as sysfs attributes: > - ber_cnt (bus error count) > - nack_cnt (NACK count) > - rec_fail_cnt, rec_succ_cnt (recovery failure/success count) > - timeout_cnt (timeout count) > - i2c_speed (bus frequency) > - tx_complete_cnt (transaction completed, including both as an initiator > and as a target) > > The function i2c_adapter_create_stats_folder creates a stats directory > in the device's sysfs directory to hold the debug counters. The platform > drivers are responsible for instantiating the counters in the stats > directory if applicable. [] > diff --git a/drivers/i2c/i2c-dev.c b/drivers/i2c/i2c-dev.c [] > +void i2c_adapter_create_stats_folder(struct i2c_adapter* adapter) { > + adapter->stats = kzalloc(sizeof(struct i2c_adapter_stats), GFP_KERNEL); unchecked alloc, could fail. > + adapter->stats->kobj = kobject_create_and_add("stats", &adapter->dev.kobj);; > +} > + > +void i2c_adapter_stats_register_counter(struct i2c_adapter* adapter, > + const char* counter_name, void* data_source) { > + int ret; > + if (adapter->stats == NULL) { > + i2c_adapter_create_stats_folder(adapter); > + } So all of these adapter->stats dereferences could oops. > + if (!strcmp(counter_name, "ber_cnt")) { > + adapter->stats->ber_cnt = data_source; > + ret = sysfs_create_file(adapter->stats->kobj, &dev_attr_ber_cnt.attr); > + } else if (!strcmp(counter_name, "nack_cnt")) { > + adapter->stats->nack_cnt = data_source; > + ret = sysfs_create_file(adapter->stats->kobj, &dev_attr_nack_cnt.attr); > + } else if (!strcmp(counter_name, "rec_succ_cnt")) { > + adapter->stats->rec_succ_cnt = data_source; > + ret = sysfs_create_file(adapter->stats->kobj, &dev_attr_rec_succ_cnt.attr); > + } else if (!strcmp(counter_name, "rec_fail_cnt")) { > + adapter->stats->rec_fail_cnt = data_source; > + ret = sysfs_create_file(adapter->stats->kobj, &dev_attr_rec_fail_cnt.attr); > + } else if (!strcmp(counter_name, "timeout_cnt")) { > + adapter->stats->timeout_cnt = data_source; > + ret = sysfs_create_file(adapter->stats->kobj, &dev_attr_timeout_cnt.attr); > + } else if (!strcmp(counter_name, "i2c_speed")) { > + adapter->stats->i2c_speed = data_source; > + ret = sysfs_create_file(adapter->stats->kobj, &dev_attr_i2c_speed.attr); > + } else if (!strcmp(counter_name, "tx_complete_cnt")) { > + adapter->stats->tx_complete_cnt = data_source; > + ret = sysfs_create_file(adapter->stats->kobj, &dev_attr_tx_complete_cnt.attr); > + } and if none of the strcmp comparisons match, ret is uninitialized. > + > + if (ret) { > + printk("Failed to create sysfs file for %s", counter_name); pr_ and should have a terminating newline