Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752151AbXEFXPE (ORCPT ); Sun, 6 May 2007 19:15:04 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752145AbXEFXPE (ORCPT ); Sun, 6 May 2007 19:15:04 -0400 Received: from py-out-1112.google.com ([64.233.166.181]:4215 "EHLO py-out-1112.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752151AbXEFXPC (ORCPT ); Sun, 6 May 2007 19:15:02 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:message-id:date:from:sender:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references:x-google-sender-auth; b=uK+VVfNT8oD4Zzl6FzsHY7PIsZXLJOob1b++UTExf8frwja8pSV/4Ebw56ywCecVcraP+yQVFE4ZZdgMHHwhmDcaI9yuHTsHsJyFx4mOk54ZQfeFSDxcEtslwLbgxYJk2g6LriIB6XUnFaanxigFoXe0j0wA2dOzXOtDWS8TyJY= Message-ID: <2c0942db0705061615i1c6147a1h6aca54012c3509aa@mail.gmail.com> Date: Sun, 6 May 2007 16:15:00 -0700 From: "Ray Lee" To: "Alan Stern" Subject: Re: [PATCH] make hci_notifier a blocking notifier (was Re: BUG: sleeping function called from invalid context at net/core/sock.c:1523) Cc: "Satyam Sharma" , LKML , "Pavel Machek" , "Rafael J. Wysocki" , "Max Krasnyansky" , marcel@holtmann.org, "pm list" In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline References: X-Google-Sender-Auth: fa430e3155a3d133 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1568 Lines: 36 On 5/6/07, Alan Stern wrote: > On Sun, 6 May 2007, Satyam Sharma wrote: > > > Anyway, the hci_notifier is called from the following six call sites: > > > > hci_dev_open() and hci_dev_close() -> both called from > > hci_sock_ioctl() => both can sleep > > hci_register_dev() and hci_unregister_dev() => again both are capable > > of sleeping > > hci_suspend_dev() and hci_resume_dev() -> called from the .suspend() > > and .resume() of the hci_usb_driver, and again both of these can sleep > > > > Is there any other reason why hci_notifier must be an atomic notifier? > > > > (CC'ing Alan Stern just in case, apparently hci_notifier became atomic > > when notifier chains were classified into atomic / blocking) > > I don't remember exactly why this particular choice was made. Perhaps we > found that the notifier callout routines didn't use any blocking > primitives (we may have been mistaken about this -- there was a lot of > code to check) and so therefore the choice didn't matter. In that case we > probably just decided to make it an atomic notifier to keep things simple. > > As you found, changing it to a blocking notifier is very easy. Provided > all the callers are non-atomic it should work just fine. Okay, I'll go ahead and try the patch, then, and report back. Thanks, Ray - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/