From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758879Ab3KMLVb (ORCPT ); Wed, 13 Nov 2013 06:21:31 -0500 Received: from arkanian.console-pimps.org ([212.110.184.194]:44395 "EHLO arkanian.console-pimps.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758646Ab3KMLV0 (ORCPT ); Wed, 13 Nov 2013 06:21:26 -0500 Date: Wed, 13 Nov 2013 11:21:23 +0000 From: Matt Fleming To: Madper Xie Cc: "linux-kernel@vger.kernel.org" , "linux-efi@vger.kernel.org" , Matt Fleming Subject: Re: [BUG]: DELL XPS 8500 become a brick after fill too many entries to nvram. Message-ID: <20131113112052.GJ22636@console-pimps.org> References: <87fvr3h3b9.fsf@redhat.com> <20131111110701.GE22636@console-pimps.org> <87eh6nt8oo.fsf@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87eh6nt8oo.fsf@redhat.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 11 Nov, at 08:38:31PM, Madper Xie wrote: > > matt@console-pimps.org writes: > > > On Mon, 11 Nov, at 02:15:22PM, Madper Xie wrote: > >> Howdy all, > >> For now we ensure at least ~5kb free space. But my dell xps still > >> become a brick after I add too many entries to my nvram. So maybe 5kb > >> is not safe enough. and 5kb is just aginst Samsung's laptop. > >> So should we enlarge EFI_MIN_RESERVE? > > > > Urgh............. > > > > Thanks for the report. Could you provide some more details? > > > > - Is your machine definitely bricked? > Yes, pretty sure. After I press power button, the screen shows "DELL" > and hangs. I can't step into any configure interface and the keyboard is > dead. (NumLock led on, and I can't turn it off.) Of course my kernel > won't be loaded. The only way to fix it is change the jump line which is > on the motherboard. OK, that's pretty conclusive. Thanks. > > - Have you got a dmesg from the machine before it broke? > No. But with a diagnostic kernel(without change the behavior of > efi. Simply print total size and remain size when I write something to > nvram. Provided by Lenny), I got following output: Have you been able to calculate the safe limit of NVRAM we need to reserve to avoid bricking your machine? I was interested in the DMI and other firmware strings from dmesg. -- Matt Fleming, Intel Open Source Technology Center