From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754985Ab3KUTRU (ORCPT ); Thu, 21 Nov 2013 14:17:20 -0500 Received: from mx1.redhat.com ([209.132.183.28]:12177 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752116Ab3KUTRT (ORCPT ); Thu, 21 Nov 2013 14:17:19 -0500 Date: Thu, 21 Nov 2013 14:16:53 -0500 From: Vivek Goyal To: Greg KH Cc: linux-kernel@vger.kernel.org, kexec@lists.infradead.org, ebiederm@xmission.com, hpa@zytor.com, mjg59@srcf.ucam.org Subject: Re: [PATCH 4/6] kexec: A new system call, kexec_file_load, for in kernel kexec Message-ID: <20131121191653.GM16208@redhat.com> References: <1384969851-7251-1-git-send-email-vgoyal@redhat.com> <1384969851-7251-5-git-send-email-vgoyal@redhat.com> <20131121190350.GC17070@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20131121190350.GC17070@kroah.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 Thu, Nov 21, 2013 at 11:03:50AM -0800, Greg KH wrote: > On Wed, Nov 20, 2013 at 12:50:49PM -0500, Vivek Goyal wrote: > > This patch implements the in kernel kexec functionality. It implements a > > new system call kexec_file_load. I think parameter list of this system > > call will change as I have not done the kernel image signature handling > > yet. I have been told that I might have to pass the detached signature > > and size as part of system call. > > This could be done as we do with modules, and just tack the signature > onto the end of the 'blob' of the image. That way we could use the same > tool to sign the binary as we do for modules, and save the need for > extra parameters in the syscall. I was hoping to do that. Just that we will have to somehow resolve the conflict with PE/COFF authenticode signature of kernel. > > > +/* > > + * Free up tempory buffers allocated which are not needed after image has > > + * been loaded. > > + * > > + * Free up memory used by kernel, initrd, and comand line. This is temporary > > + * memory allocation which is not needed any more after these buffers have > > + * been loaded into separate segments and have been copied elsewhere > > + */ > > +static void kimage_file_post_load_cleanup(struct kimage *image) > > +{ > > + if (image->kernel_buf) { > > + vfree(image->kernel_buf); > > + image->kernel_buf = NULL; > > + } > > + > > + if (image->initrd_buf) { > > + vfree(image->initrd_buf); > > + image->initrd_buf = NULL; > > + } > > + > > + if (image->cmdline_buf) { > > + vfree(image->cmdline_buf); > > + image->cmdline_buf = NULL; > > + } > > No need to check the buffer before calling vfree(), it can handle NULL > just fine. Ok, I will remove this extra non-null check. Thanks Vivek