Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933984AbbDQNuf (ORCPT ); Fri, 17 Apr 2015 09:50:35 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:34376 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933973AbbDQNuU (ORCPT ); Fri, 17 Apr 2015 09:50:20 -0400 Date: Fri, 17 Apr 2015 15:50:16 +0200 From: Greg KH To: Roy Franz Cc: Andy Lutomirski , Borislav Petkov , Matt Fleming , Ong Boon Leong , "linux-efi@vger.kernel.org" , Sam Protsenko , "Kweh, Hock Leong" , LKML , Peter Jones , Ming Lei Subject: Re: [PATCH v4 2/2] efi: an sysfs interface for user to update efi firmware Message-ID: <20150417135016.GC19794@kroah.com> References: <1429004697-28320-1-git-send-email-hock.leong.kweh@intel.com> <1429004697-28320-3-git-send-email-hock.leong.kweh@intel.com> <20150414140914.GE5989@kroah.com> <20150415132000.GD21491@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2801 Lines: 59 On Wed, Apr 15, 2015 at 05:19:09PM -0700, Roy Franz wrote: > On Wed, Apr 15, 2015 at 8:45 AM, Andy Lutomirski wrote: > > On Apr 15, 2015 6:20 AM, "Greg Kroah-Hartman" > > wrote: > >> > >> On Tue, Apr 14, 2015 at 11:52:48AM -0400, Andy Lutomirski wrote: > >> > On Tue, Apr 14, 2015 at 10:09 AM, Greg Kroah-Hartman > >> > wrote: > >> > > On Tue, Apr 14, 2015 at 05:44:56PM +0800, Kweh, Hock Leong wrote: > >> > >> From: "Kweh, Hock Leong" > >> > >> > >> > >> Introducing a kernel module to expose capsule loader interface > >> > >> for user to upload capsule binaries. This module leverage the > >> > >> request_firmware_direct_full_path() to obtain the binary at a > >> > >> specific path input by user. > >> > >> > >> > >> Example method to load the capsule binary: > >> > >> echo -n "/path/to/capsule/binary" > /sys/devices/platform/efi_capsule_loader/capsule_loader > >> > > > >> > > Ick, why not just have the firmware file location present, and copy it > >> > > to the sysfs file directly from userspace, instead of this two-step > >> > > process? > >> > > >> > Because it's not at all obvious how error handling should work in that case. > >> > >> I don't understand how the error handling is any different. The kernel > >> ends up copying the data in through the firmware interface both ways, we > >> just aren't creating yet-another-firmware-path in the system. > > > > If I run uefi-update-capsule foo.bin, I want it to complain if the > > UEFI call fails. In contrast, if I boot and my ath10k firmware is > > bad, there's no explicit user interaction that should fail; instead I > > have no network device and I get to read the logs and figure out why. > > IOW bad volatile device firmware is just like a bad device driver, > > whereas bad UEFI capsules are problems that should be reported to > > whatever tried to send them to UEFI. > > > > --Andy > > > There are several types of errors that can be returned by > UpdateCapsule(), allowing > us to distinguish between capsules that are not supported by the > platform, capsules > that must be updated at boot time, and capsule updates that failed due > to a device error. > I think we really do want this type of information returned to capsule loader. Ok, all of that sounds like you really want a character device, with an ioctl, to do this. Just use a misc device and your infrastructure will be handled for you (sysfs, character device, etc.) and away you go. thanks, greg k-h -- 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/