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 lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id C7F2BC77B73 for ; Tue, 2 May 2023 15:24:29 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ptrrB-0002fq-Fs; Tue, 02 May 2023 11:23:57 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ptrr9-0002ff-KY for qemu-devel@nongnu.org; Tue, 02 May 2023 11:23:55 -0400 Received: from mail-wm1-x32e.google.com ([2a00:1450:4864:20::32e]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1ptrr6-0007C7-Rp for qemu-devel@nongnu.org; Tue, 02 May 2023 11:23:55 -0400 Received: by mail-wm1-x32e.google.com with SMTP id 5b1f17b1804b1-3f19ab994ccso40988265e9.2 for ; Tue, 02 May 2023 08:23:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1683041028; x=1685633028; h=content-transfer-encoding:mime-version:message-id:in-reply-to:date :subject:cc:to:from:user-agent:references:from:to:cc:subject:date :message-id:reply-to; bh=sIM35jzKED3mMrx8j+jeQ0hrfGDMMvjf7sb3RVQRKLU=; b=rUiyQ5KiVG5nzVqEMyHep5M2APMG5jpoIV2WrVrYgtnuyLTsU589otTiDZEi+1BIVe JTPUQL7PCMELIFkDkCsAhpRRqdVJyW4loJTo0hLtKPUOHkxjzOJ8Dg3mMsaCu1FUdn0U F5273blEEaOtcKpWOrkiTxb2GEmHkoEHsIgXpR73mrzZh3tTBUZNePKomQgQQgQxByO/ tSylHgZOpWTDR3KwV/DmxlunuYw8gd6+vxJD/BMXhj5Ny8pLtHJbFI3Xp39g7T1GSrbu lq/xMHkdiOBG2qVFyQQ/1M9iy6pruDq50GePNbafXdPUV9HiDQRGKoXC2bRSpsFshOwc HeYw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1683041028; x=1685633028; h=content-transfer-encoding:mime-version:message-id:in-reply-to:date :subject:cc:to:from:user-agent:references:x-gm-message-state:from:to :cc:subject:date:message-id:reply-to; bh=sIM35jzKED3mMrx8j+jeQ0hrfGDMMvjf7sb3RVQRKLU=; b=QkZbUq/6LbAY5z5Hr9Q1vNNy76/iblJyfyxNPl8lSAmL9CC63pjoPBqqNwS01hFFsc ENJE/P+HKjRVpx6lDRuaH+t+XxNwMC3b19iwZc419Llh2/4dpYYBZ1mGtanEDmMbdOxK VbaoRQ8oWL82yTC4VG6xZLtcqKlwtbnbqWZqvNGE5CK1wP+bQCZFbqxEU2roGpTIJXyI iHkWm2E/m21UtqCPk4YhtnJN66nqBe0kt0SNLgB2wUOL3JNhpYjhg55C9U24+54w0jZI 95AppD07dq4toNHZOiTEYSFE+YiP99kiUp9iKhKp5ygpB8pjJsOzpeS+IBZ0G2dhorB1 15sw== X-Gm-Message-State: AC+VfDz3pnI/0SdJbb+ZtFGOKVl5qLpApgt4265iIwXJw8+sIzIIjCzM pODf/+jwDx+fUVP8MaW0GwWe5Q== X-Google-Smtp-Source: ACHHUZ5J3R1DwgmG3tpTUPXBCYN6FQuk46DQLU2JiEpbu9Bk058pAvDua5f4xOyuOISMsVE0Dm/brg== X-Received: by 2002:a7b:c40f:0:b0:3f0:8034:f77e with SMTP id k15-20020a7bc40f000000b003f08034f77emr12187788wmi.20.1683041028388; Tue, 02 May 2023 08:23:48 -0700 (PDT) Received: from zen.linaroharston ([85.9.250.243]) by smtp.gmail.com with ESMTPSA id h7-20020a5d6e07000000b003048084a57asm21731395wrz.79.2023.05.02.08.23.47 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 02 May 2023 08:23:48 -0700 (PDT) Received: from zen (localhost [127.0.0.1]) by zen.linaroharston (Postfix) with ESMTP id D1BE41FFBA; Tue, 2 May 2023 16:23:46 +0100 (BST) References: <20230208192654.8854-1-farosas@suse.de> <5f6a831e-016b-ce13-3e55-722944161c4d@redhat.com> User-agent: mu4e 1.11.4; emacs 29.0.90 From: Alex =?utf-8?Q?Benn=C3=A9e?= To: Thomas Huth Cc: Philippe =?utf-8?Q?Mathieu-Daud=C3=A9?= , Fabiano Rosas , qemu-devel@nongnu.org, Paolo Bonzini Subject: Re: [PATCH v2 00/10] Kconfig vs. default devices Date: Tue, 02 May 2023 16:20:09 +0100 In-reply-to: <5f6a831e-016b-ce13-3e55-722944161c4d@redhat.com> Message-ID: <87fs8eu58d.fsf@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Received-SPF: pass client-ip=2a00:1450:4864:20::32e; envelope-from=alex.bennee@linaro.org; helo=mail-wm1-x32e.google.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Thomas Huth writes: > On 08/02/2023 20.43, Philippe Mathieu-Daud=C3=A9 wrote: >> On 8/2/23 20:26, Fabiano Rosas wrote: >>=20 >>> We currently have a situation where disabling a Kconfig might result >>> in a runtime error when QEMU selects the corresponding device as a >>> default value for an option. But first a disambiguation: >>> >>> Kconfig default:: >>> =C2=A0=C2=A0 a device "Foo" for which there's "config FOO default y" or= "config X >>> =C2=A0=C2=A0 imply FOO" in Kconfig. >>> >>> QEMU hardcoded default:: >>> =C2=A0=C2=A0 a fallback; a device "Foo" that is chosen in case no corre= sponding >>> =C2=A0=C2=A0 option is given in the command line. >>> >>> The issue I'm trying to solve is that there is no link between the two >>> "defaults" above, which means that when the user at build time >>> de-selects a Kconfig default, either via configs/devices/*/*.mak or >>> --without-default-devices, the subsequent invocation at runtime might >>> continue to try to create the missing device due to QEMU defaults. >> This will keep bitrotting if we don't cover such configs in our CI. >> Why do you want to get this fixed BTW? I'm not sure there is a big >> interest (as in "almost no users"). >> I tried to do that few years ago [*] and Thomas said: >> "in our CI, we should test what users really need, >> =C2=A0and not each and every distantly possible combination." > > You're mis-quoting me here. That comment was made when we were talking > about very arbitrary configs that likely nobody is going to use. > Fabiano's series here is about the --without-default-devices configure > option which everybody could add to their set of "configure" options > easily. Indeed - while trying to reduce the compile time I ran into this with a plain --without-default-devices check. We also have in the meantime introduced --with-devices-FOO so we can do minimal builds. > > Thomas --=20 Alex Benn=C3=A9e Virtualisation Tech Lead @ Linaro