From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753218Ab2KFW5o (ORCPT ); Tue, 6 Nov 2012 17:57:44 -0500 Received: from mga14.intel.com ([143.182.124.37]:32828 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751412Ab2KFW5m (ORCPT ); Tue, 6 Nov 2012 17:57:42 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.80,724,1344236400"; d="scan'208";a="165261427" From: "Woodhouse, David" To: Krzysztof Mazur CC: "netdev@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Chas Williams - CONTRACTOR , "davem@davemloft.net" Subject: Re: [PATCH v3 5/7] pppoatm: take ATM socket lock in pppoatm_send() Thread-Topic: [PATCH v3 5/7] pppoatm: take ATM socket lock in pppoatm_send() Thread-Index: AQHNvGz3+/ZM1gSqR0mkUiHOeUa5KJfda2IA Date: Tue, 6 Nov 2012 22:57:39 +0000 Message-ID: <1352242658.7340.19.camel@shinybook.infradead.org> References: <1352240222-363-1-git-send-email-krzysiek@podlesie.net> <1352240222-363-6-git-send-email-krzysiek@podlesie.net> In-Reply-To: <1352240222-363-6-git-send-email-krzysiek@podlesie.net> Accept-Language: en-GB, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.252.122.128] Content-Type: text/plain; charset="utf-8" Content-ID: <1DDACE81D6B5FA409A8BD38C858EA4BA@intel.com> MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from base64 to 8bit by mail.home.local id qA6MvkM8017521 On Tue, 2012-11-06 at 23:17 +0100, Krzysztof Mazur wrote: > + if (sock_owned_by_user(sk_atm(vcc))) > + goto nospace; I still think this one can lead to an infinite stall of the PPP channel, because we return 0 from pppoatm_send() but never make a later call to ppp_output_wakeup() to unblock it. In the existing cases where we could return 0 (because pppoatm_may_send() said no), we were careful to set the BLOCKED flag and we *knew* that a packet was in flight so we'd get to wake it up again on a subsequent pppoatm_pop(). None of that works for this new code path that returns zero. -- Sent with MeeGo's ActiveSync support. David Woodhouse Open Source Technology Centre David.Woodhouse@intel.com Intel Corporation {.n++%ݶw{.n+{G{ayʇڙ,jfhz_(階ݢj"mG?&~iOzv^m ?I