From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Vladislav Zolotarov" Subject: [PATCH net-next] bnx2x: Resolving a possible dead-lock situation Date: Tue, 23 Nov 2010 18:15:12 +0200 Message-ID: <1290528912.15453.3.camel@lb-tlvb-vladz> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: "Eilon Greenstein" , "netdev list" To: "Dave Miller" Return-path: Received: from mms2.broadcom.com ([216.31.210.18]:1771 "EHLO mms2.broadcom.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753708Ab0KWQPt (ORCPT ); Tue, 23 Nov 2010 11:15:49 -0500 Sender: netdev-owner@vger.kernel.org List-ID: There is a possible dead-lock situation between sch_direct_xmit() (called from soft_IRQ context) and bnx2x_tx_int() when called from an ethtool self-test flow (syscall context). To prevent a dead-lock, disable bottom-halves on a local CPU when taking a tx_lock from bnx2x_tx_int() (use __netif_tx_lock_bh(txq)). The flow in the bnx2x_tx_int() where tx_lock is taken should be hit very rarely thus performance penalty of this change should be minimal. Signed-off-by: Vladislav Zolotarov Signed-off-by: Eilon Greenstein --- drivers/net/bnx2x/bnx2x_cmn.c | 4 ++-- 1 files changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/net/bnx2x/bnx2x_cmn.c b/drivers/net/bnx2x/bnx2x_cmn.c index 94d5f59..5189788 100644 --- a/drivers/net/bnx2x/bnx2x_cmn.c +++ b/drivers/net/bnx2x/bnx2x_cmn.c @@ -144,14 +144,14 @@ int bnx2x_tx_int(struct bnx2x_fastpath *fp) * stops the queue */ - __netif_tx_lock(txq, smp_processor_id()); + __netif_tx_lock_bh(txq); if ((netif_tx_queue_stopped(txq)) && (bp->state == BNX2X_STATE_OPEN) && (bnx2x_tx_avail(fp) >= MAX_SKB_FRAGS + 3)) netif_tx_wake_queue(txq); - __netif_tx_unlock(txq); + __netif_tx_unlock_bh(txq); } return 0; } -- 1.7.0.4