From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Hemminger Subject: [PATCH] sky2: recovery deadlock fix Date: Mon, 3 Dec 2007 17:02:17 -0800 Message-ID: <20071203170217.492d9eb9@freepuppy.rosehill> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org To: Jeff Garzik Return-path: Received: from smtp2.linux-foundation.org ([207.189.120.14]:58280 "EHLO smtp2.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751202AbXLDBD0 (ORCPT ); Mon, 3 Dec 2007 20:03:26 -0500 Sender: netdev-owner@vger.kernel.org List-ID: Prevent deadlock in sky2 recovery logic. sky2_down calls napi_synchronize which gets stuck if napi was already disabled. Fix by rearranging slightly and not calling napi_disable until after both ports are stopped. The napi_disable probably is being overly paranoid, but it is safe now. Signed-off-by: Stephen Hemminger --- Please apply for 2.6.24 (upstream-fixes) --- a/drivers/net/sky2.c 2007-11-30 16:51:50.000000000 -0800 +++ b/drivers/net/sky2.c 2007-11-30 16:54:52.000000000 -0800 @@ -2906,16 +2906,14 @@ static void sky2_restart(struct work_str int i, err; rtnl_lock(); - sky2_write32(hw, B0_IMSK, 0); - sky2_read32(hw, B0_IMSK); - napi_disable(&hw->napi); - for (i = 0; i < hw->ports; i++) { dev = hw->dev[i]; if (netif_running(dev)) sky2_down(dev); } + napi_disable(&hw->napi); + sky2_write32(hw, B0_IMSK, 0); sky2_reset(hw); sky2_write32(hw, B0_IMSK, Y2_IS_BASE); napi_enable(&hw->napi);