Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752782AbbLLUHJ (ORCPT ); Sat, 12 Dec 2015 15:07:09 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:35774 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752306AbbLLUGd (ORCPT ); Sat, 12 Dec 2015 15:06:33 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Moni Shoua , Jack Morgenstein , Eran Ben Elisha , Or Gerlitz , "David S. Miller" Subject: [PATCH 4.2 16/61] net/mlx4_core: Fix sleeping while holding spinlock at rem_slave_counters Date: Sat, 12 Dec 2015 12:05:44 -0800 Message-Id: <20151212200457.970947625@linuxfoundation.org> X-Mailer: git-send-email 2.6.4 In-Reply-To: <20151212200457.170255093@linuxfoundation.org> References: <20151212200457.170255093@linuxfoundation.org> User-Agent: quilt/0.64 MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3202 Lines: 94 4.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eran Ben Elisha [ Upstream commit f5adbfee72282bb1f456d52b04adacd4fe6ac502 ] When cleaning slave's counter resources, we hold a spinlock that protects the slave's counters list. As part of the clean, we call __mlx4_clear_if_stat which calls mlx4_alloc_cmd_mailbox which is a sleepable function. In order to fix this issue, hold the spinlock, and copy all counter indices into a temporary array, and release the spinlock. Afterwards, iterate over this array and free every counter. Repeat this scenario until the original list is empty (a new counter might have been added while releasing the counters from the temporary array). Fixes: b72ca7e96acf ("net/mlx4_core: Reset counters data when freed") Reported-by: Moni Shoua Tested-by: Moni Shoua Signed-off-by: Jack Morgenstein Signed-off-by: Eran Ben Elisha Signed-off-by: Or Gerlitz Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/net/ethernet/mellanox/mlx4/resource_tracker.c | 39 ++++++++++++------ 1 file changed, 27 insertions(+), 12 deletions(-) --- a/drivers/net/ethernet/mellanox/mlx4/resource_tracker.c +++ b/drivers/net/ethernet/mellanox/mlx4/resource_tracker.c @@ -4934,26 +4934,41 @@ static void rem_slave_counters(struct ml struct res_counter *counter; struct res_counter *tmp; int err; - int index; + int *counters_arr = NULL; + int i, j; err = move_all_busy(dev, slave, RES_COUNTER); if (err) mlx4_warn(dev, "rem_slave_counters: Could not move all counters - too busy for slave %d\n", slave); - spin_lock_irq(mlx4_tlock(dev)); - list_for_each_entry_safe(counter, tmp, counter_list, com.list) { - if (counter->com.owner == slave) { - index = counter->com.res_id; - rb_erase(&counter->com.node, - &tracker->res_tree[RES_COUNTER]); - list_del(&counter->com.list); - kfree(counter); - __mlx4_counter_free(dev, index); + counters_arr = kmalloc_array(dev->caps.max_counters, + sizeof(*counters_arr), GFP_KERNEL); + if (!counters_arr) + return; + + do { + i = 0; + j = 0; + spin_lock_irq(mlx4_tlock(dev)); + list_for_each_entry_safe(counter, tmp, counter_list, com.list) { + if (counter->com.owner == slave) { + counters_arr[i++] = counter->com.res_id; + rb_erase(&counter->com.node, + &tracker->res_tree[RES_COUNTER]); + list_del(&counter->com.list); + kfree(counter); + } + } + spin_unlock_irq(mlx4_tlock(dev)); + + while (j < i) { + __mlx4_counter_free(dev, counters_arr[j++]); mlx4_release_resource(dev, slave, RES_COUNTER, 1, 0); } - } - spin_unlock_irq(mlx4_tlock(dev)); + } while (i); + + kfree(counters_arr); } static void rem_slave_xrcdns(struct mlx4_dev *dev, int slave) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/