From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jan-Bernd Themann Subject: Re: [PATCH 2/2] ehea: add memory remove hotplug support Date: Mon, 4 Feb 2008 16:24:30 +0100 Message-ID: <200802041624.31228.ossthema@de.ibm.com> References: <200802041404.49960.ossthema@de.ibm.com> <1202136362.7672.5.camel@concordia> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Cc: Jeff Garzik , Thomas Klein , Jan-Bernd Themann , netdev , linux-kernel , linux-ppc , Christoph Raisch , Marcus Eder To: michael@ellerman.id.au Return-path: Received: from mtagate2.uk.ibm.com ([195.212.29.135]:28401 "EHLO mtagate2.uk.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751291AbYBDPYh (ORCPT ); Mon, 4 Feb 2008 10:24:37 -0500 In-Reply-To: <1202136362.7672.5.camel@concordia> Content-Disposition: inline Sender: netdev-owner@vger.kernel.org List-ID: On Monday 04 February 2008 15:46, Michael Ellerman wrote: > On Mon, 2008-02-04 at 14:04 +0100, Jan-Bernd Themann wrote: > > Add memory remove hotplug support > > @@ -3559,6 +3578,10 @@ int __init ehea_module_init(void) > > if (ret) > > ehea_info("failed registering reboot notifier"); > > > > + ret = register_memory_notifier(&ehea_mem_nb); > > + if (ret) > > + ehea_info("failed registering memory remove notifier"); > > > > ret = crash_shutdown_register(&ehea_crash_handler); > > if (ret) > > ehea_info("failed registering crash handler"); > > You don't do anything except print a message if the registration fails. > What happens when someone tries to remove memory but the memory notifier > wasn't registered properly? Bang? In case the registration fails and somebody tries to free memory: - Driver will not remove the affected memory from the eHEA memory region --> Firmware (phyp) can not free that memory (as marked as used) --> Therefore the removed memory could not be used in an other partition It makes sense to allow the driver to work anyway. Having no ethernet would not really be a good alternative. Regards, Jan-Bernd