From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp-out.google.com ([74.125.121.35]:1401 "EHLO smtp-out.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753769Ab0DSTHA (ORCPT ); Mon, 19 Apr 2010 15:07:00 -0400 Received: from wpaz33.hot.corp.google.com (wpaz33.hot.corp.google.com [172.24.198.97]) by smtp-out.google.com with ESMTP id o3JJ6vQc008180 for ; Mon, 19 Apr 2010 21:06:58 +0200 Received: from wya21 (wya21.prod.google.com [10.241.225.21]) by wpaz33.hot.corp.google.com with ESMTP id o3JJ6uag027046 for ; Mon, 19 Apr 2010 12:06:56 -0700 Received: by wya21 with SMTP id 21so185348wya.29 for ; Mon, 19 Apr 2010 12:06:56 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <1271703705.15004.4.camel@c-dwalke-linux.qualcomm.com> References: <1271700189-8376-5-git-send-email-dwalker@codeaurora.org> <1271703705.15004.4.camel@c-dwalke-linux.qualcomm.com> Date: Mon, 19 Apr 2010 12:06:55 -0700 Message-ID: Subject: Re: [PATCH 5/5] arm: msm: smd: fix SMD modem processor sync condition From: Dima Zavin Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-arm-msm-owner@vger.kernel.org List-ID: To: Daniel Walker Cc: linux-arm-msm@vger.kernel.org On Mon, Apr 19, 2010 at 12:01 PM, Daniel Walker wrote: > On Mon, 2010-04-19 at 11:34 -0700, Dima Zavin wrote: >> Do we really need a formalized blocking point here? The apps processor >> can do other useful initialization work while the modem is booting. >> The first time you do a proc_comm call, it checks the PCOM_READY >> state, and will block anyway. Preventing the apps processor from >> continuing until then is suboptimal. If there are bugs in the modem >> code where it incorrectly stomps on shared resources, then those >> should be fixed. This patch looks like a hack to me. > > > Yes, we need to formalize a blocking point .. The apps processor waits > in this way no matter what you do .. Like your saying above "The first > time you do a proc_comm call, it checks the PCOM_READY state, and will > block anyway" that's a hack .. What your saying is _maybe_ there exists > a proc_comm call early enough to prevent a crash, or maybe not .. That's > not formal enough. That's not at all what I am saying. There's no maybe. If I don't need anything from the modem, I won't make a proc_comm call. If there is a crash because the modem is modifying shared resources that affect the apps processor without an appropriate synchronization point, then it's a bug on the modem side. Making this change will only mask modem bugs. --Dima > This patch makes this a formal process with a comment explain what is > happening, and we will never see a crash related to this again. > > Daniel > >