From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757149AbcG1THY (ORCPT ); Thu, 28 Jul 2016 15:07:24 -0400 Received: from mail-il-dmz.mellanox.com ([193.47.165.129]:36641 "EHLO mellanox.co.il" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1755712AbcG1THU (ORCPT ); Thu, 28 Jul 2016 15:07:20 -0400 From: Chris Metcalf To: Joe Perches , Matt Fleming , Arnd Bergmann , "Greg Kroah-Hartman" , Ferruh Yigit , Dmitry Torokhov , Jaroslav Kysela , Takashi Iwai Cc: Chris Metcalf , LKML Subject: [PATCH] tile-srom: avoid krealloc(... __GFP_ZERO) pattern Date: Thu, 28 Jul 2016 15:07:04 -0400 Message-Id: <1469732824-21572-1-git-send-email-cmetcalf@mellanox.com> X-Mailer: git-send-email 2.7.2 In-Reply-To: <1469729491.3998.58.camel@perches.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Joe Perches points out [1] that this pattern isn't currently safe. This driver doesn't really need the zeroing semantic anyway; by restructuring the code slightly we can initialize all the fields of the structure up front instead. [1] https://lkml.kernel.org/r/1469729491.3998.58.camel@perches.com Signed-off-by: Chris Metcalf --- drivers/char/tile-srom.c | 28 +++++++++++++++------------- 1 file changed, 15 insertions(+), 13 deletions(-) diff --git a/drivers/char/tile-srom.c b/drivers/char/tile-srom.c index 69f6b4acc377..398800edb2cc 100644 --- a/drivers/char/tile-srom.c +++ b/drivers/char/tile-srom.c @@ -331,13 +331,11 @@ static const struct file_operations srom_fops = { /** * srom_setup_minor() - Initialize per-minor information. * @srom: Per-device SROM state. - * @index: Device to set up. + * @devhdl: Partition device handle. */ -static int srom_setup_minor(struct srom_dev *srom, int index) +static int srom_setup_minor(struct srom_dev *srom, int devhdl) { - struct device *dev; - int devhdl = srom->hv_devhdl; - + srom->hv_devhdl = devhdl; mutex_init(&srom->lock); if (_srom_read(devhdl, &srom->total_size, @@ -350,9 +348,7 @@ static int srom_setup_minor(struct srom_dev *srom, int index) SROM_PAGE_SIZE_OFF, sizeof(srom->page_size)) < 0) return -EIO; - dev = device_create(srom_class, &srom_parent->dev, - MKDEV(srom_major, index), srom, "%d", index); - return PTR_ERR_OR_ZERO(dev); + return 0; } /** srom_init() - Initialize the driver's module. */ @@ -365,7 +361,7 @@ static int srom_init(void) * Start with a plausible number of partitions; the krealloc() call * below will yield about log(srom_devs) additional allocations. */ - srom_devices = kzalloc(4 * sizeof(struct srom_dev), GFP_KERNEL); + srom_devices = kmalloc(4 * sizeof(struct srom_dev), GFP_KERNEL); /* Discover the number of srom partitions. */ for (i = 0; ; i++) { @@ -373,7 +369,7 @@ static int srom_init(void) char buf[20]; struct srom_dev *new_srom_devices = krealloc(srom_devices, (i+1) * sizeof(struct srom_dev), - GFP_KERNEL | __GFP_ZERO); + GFP_KERNEL); if (!new_srom_devices) { result = -ENOMEM; goto fail_mem; @@ -387,7 +383,9 @@ static int srom_init(void) i, devhdl); break; } - srom_devices[i].hv_devhdl = devhdl; + result = srom_setup_minor(&srom_devices[i], devhdl); + if (result != 0) + goto fail_mem; } srom_devs = i; @@ -431,9 +429,13 @@ static int srom_init(void) srom_class->dev_groups = srom_dev_groups; srom_class->devnode = srom_devnode; - /* Do per-partition initialization */ + /* Create per-partition devices */ for (i = 0; i < srom_devs; i++) { - result = srom_setup_minor(srom_devices + i, i); + struct device *dev = + device_create(srom_class, &srom_parent->dev, + MKDEV(srom_major, i), srom_devices + i, + "%d", i); + result = PTR_ERR_OR_ZERO(dev); if (result < 0) goto fail_class; } -- 2.7.2