From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 98241EDE9AC for ; Thu, 14 Sep 2023 11:52:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238067AbjINLwg (ORCPT ); Thu, 14 Sep 2023 07:52:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46930 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237253AbjINLwf (ORCPT ); Thu, 14 Sep 2023 07:52:35 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 63919CC3; Thu, 14 Sep 2023 04:52:31 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 94620C433C7; Thu, 14 Sep 2023 11:52:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1694692351; bh=bY6gpFweje0TA1EJp0zihUndohZBvlaM4pTha0LTaaA=; h=Date:Cc:Subject:From:To:References:In-Reply-To:From; b=HEzvOyz2sdB5n75zpEBiYGCwixAXK/g6GTkdVt1HW5h1rdduTfBe1HUp3E3NRRfvu /jCvLAk6vSoQoX4WKjqZC15948pOwjOnsN+LfWxeGDgeAc4y1brfY+0DznTwvxBtc9 On4Bbg+brNk6wsD7A1xlikvORVdB49qu2NYVpnbyg4kX9bmBQP7ZyqpiJpBr/QYTn3 Kw8UzLpetjgjWhmOJL+yne6upNiPNS7DDUv9R6sqQv2xT5mTU7HdadcrIYzcA6LIy7 nqXRk7dzZKtbQjg+PdcG8LJFRuCbvug99Y0v6jCiudlEQzr+yJKgEEo9m1C3WVsr1w RqX16PtPLdVwQ== Mime-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=UTF-8 Date: Thu, 14 Sep 2023 14:52:26 +0300 Message-Id: Cc: , , , , , , , , "Baoquan He" , , "Luca Boccassi" Subject: Re: [PATCH 0/1] x86/kexec: UKI support From: "Jarkko Sakkinen" To: "Lennart Poettering" , "Jan Hendrik Farr" X-Mailer: aerc 0.14.0 References: <20230909161851.223627-1-kernel@jfarr.cc> <1d974586-1bf7-42e8-9dae-e5e41a3dbc9f@app.fastmail.com> <9580df76-c143-4077-8a39-b1fcc0ed37bd@app.fastmail.com> In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu Sep 14, 2023 at 11:48 AM EEST, Lennart Poettering wrote: > On Di, 12.09.23 17:32, Jan Hendrik Farr (kernel@jfarr.cc) wrote: > > > >> The format itself is rather simple. It's just a PE file (as required > > >> by the UEFI spec) that contains a small stub application in the .tex= t, > > >> .data, etc sections that is responsible for invoking the contained > > >> kernel and initrd with the contained cmdline. The kernel image is > > >> placed into a .kernel section, the initrd into a .initrd section, an= d > > >> the cmdline into a .cmdline section in the PE executable. > > > > > > How does this interact with the existing EFI stub support in > > > linux? > > > > It doesn't. During normal boot of a UKI the stub in it is used > > (systemd-stub, see: > > https://www.freedesktop.org/software/systemd/man/systemd-stub.html). Th= e > > kernel's own EFI stub will still be in the binary inside the .linux > > section but not used. > > That's not true actually, if the inner kernel supports the EFI stub > then systemd-stub actually defers to that for kernel execution. It's > more portable that way, since the kernel then deals with the > differences in the boot protocol on different architectures. OK, that's nice. > Lennart > > -- > Lennart Poettering, Berlin BR, Jarkko