From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Vlad Zolotarov" Subject: [PATCH net] bnx2x: Prevent restarting Tx during bnx2x_nic_unload Date: Tue, 2 Aug 2011 10:52:37 +0300 Message-ID: <201108021052.37368.vladz@broadcom.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: "netdev@vger.kernel.org" , "Eilon Greenstein" To: "Dave Miller" Return-path: Received: from mms2.broadcom.com ([216.31.210.18]:3518 "EHLO mms2.broadcom.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751946Ab1HBHxf (ORCPT ); Tue, 2 Aug 2011 03:53:35 -0400 Sender: netdev-owner@vger.kernel.org List-ID: Tx queues were stopped before bp->state was changed to a value different from BNX2X_STATE_OPEN, which allowed the bnx2x_tx_int() called from the NAPI context to re-enable it. This then allowed the netdev->ndo_start_xmit() to be called in the middle of the function reset and rings freeing. This patch changes bp->state to a value different from BNX2X_STATE_OPEN BEFORE disabling the Tx queues in order to restore the broken protection against the above race in the bnx2x_tx_int(). Signed-off-by: Vladislav Zolotarov Signed-off-by: Eilon Greenstein --- drivers/net/bnx2x/bnx2x_cmn.c | 10 ++++++++-- 1 files changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/net/bnx2x/bnx2x_cmn.c b/drivers/net/bnx2x/bnx2x_cmn.c index 5b0dba6..d724a18 100644 --- a/drivers/net/bnx2x/bnx2x_cmn.c +++ b/drivers/net/bnx2x/bnx2x_cmn.c @@ -1989,14 +1989,20 @@ int bnx2x_nic_unload(struct bnx2x *bp, int unload_mode) return -EINVAL; } + /* + * It's important to set the bp->state to the value different from + * BNX2X_STATE_OPEN and only then stop the Tx. Otherwise bnx2x_tx_int() + * may restart the Tx from the NAPI context (see bnx2x_tx_int()). + */ + bp->state = BNX2X_STATE_CLOSING_WAIT4_HALT; + smp_mb(); + /* Stop Tx */ bnx2x_tx_disable(bp); #ifdef BCM_CNIC bnx2x_cnic_notify(bp, CNIC_CTL_STOP_CMD); #endif - bp->state = BNX2X_STATE_CLOSING_WAIT4_HALT; - smp_mb(); bp->rx_mode = BNX2X_RX_MODE_NONE; -- 1.7.4.1