From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752088AbcEDNhB (ORCPT ); Wed, 4 May 2016 09:37:01 -0400 Received: from mail-wm0-f50.google.com ([74.125.82.50]:37711 "EHLO mail-wm0-f50.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751268AbcEDNg7 (ORCPT ); Wed, 4 May 2016 09:36:59 -0400 Date: Wed, 4 May 2016 14:36:56 +0100 From: Matt Fleming To: Borislav Petkov Cc: linux-efi@vger.kernel.org, linux-kernel@vger.kernel.org, Ard Biesheuvel , Kweh Hock Leong , "Bryan O'Donoghue" , joeyli Subject: Re: [PATCH] efi/capsule: Make efi_capsule_pending() lockless Message-ID: <20160504133656.GJ2839@codeblueprint.co.uk> References: <1462054407-9735-1-git-send-email-matt@codeblueprint.co.uk> <20160503090229.GC27540@pd.tnic> <20160503141201.GW2839@codeblueprint.co.uk> <20160504093031.GA4074@pd.tnic> <20160504114605.GH2839@codeblueprint.co.uk> <20160504122042.GB4074@pd.tnic> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160504122042.GB4074@pd.tnic> User-Agent: Mutt/1.5.24+41 (02bc14ed1569) (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 04 May, at 02:20:42PM, Borislav Petkov wrote: > On Wed, May 04, 2016 at 12:46:05PM +0100, Matt Fleming wrote: > > But emergency_restart() is called after bust_spinlocks(0) which can > > reset oops_in_progress, so can't even use that to solve the panic > > case. > > Blergh. > > So I guess you need an explicit call efi_stop_capsules() somewhere in > the reboot path and be done with it. No reboot notifiers, no bla bla. > Just one big hammer which STFU the EFI. But you can't block in the reboot path and you can't guarantee you'll interrupt an in-progress EFI capsule update call that started before you entered the reboot path.