From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.alien8.de (mail.alien8.de [65.109.113.108]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 04F523A0B20; Wed, 14 Jan 2026 15:47:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=65.109.113.108 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768405645; cv=none; b=X908mYV16jV4zWT3xPQWvdE2NUuV2Jw/9R1hW4ijY4+jgHcDw0ZasC9MdahBZKoX1SR96301VXFG9iw74UtPMT7oM0a5ApGX4HXfpWXQLd4IEBR7ywGFE84XXojjlMyECu8gzXWNSZ1v8FlKLyshkt+Bqx3D5Nr98voYS0SNpOQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768405645; c=relaxed/simple; bh=UPnHOPIjGmubnCAzxv2GweargRz8EcqG9W3rLov+k0Q=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=uV1sOqk1ewRcP/k79xXoGltJFdDBwIpnzLRWLNF6vZG8oeWkX4YJ1eV3a3ewaCoEb3ppa6Fpg05+bxLIJKUI+OED2uAVaaSTf7Eq2u0h/UjWR3A8KiAtvLVawPnFEEK28e2+toV9aA+GfnLNYRAuSLTFi7PEF1JFuWPdMYP4rTE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=alien8.de; spf=pass smtp.mailfrom=alien8.de; dkim=pass (4096-bit key) header.d=alien8.de header.i=@alien8.de header.b=gDEI+zFP; arc=none smtp.client-ip=65.109.113.108 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=alien8.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=alien8.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (4096-bit key) header.d=alien8.de header.i=@alien8.de header.b="gDEI+zFP" Received: from localhost (localhost.localdomain [127.0.0.1]) by mail.alien8.de (SuperMail on ZX Spectrum 128k) with ESMTP id 5591040E0281; Wed, 14 Jan 2026 15:47:19 +0000 (UTC) X-Virus-Scanned: Debian amavisd-new at mail.alien8.de Authentication-Results: mail.alien8.de (amavisd-new); dkim=pass (4096-bit key) header.d=alien8.de Received: from mail.alien8.de ([127.0.0.1]) by localhost (mail.alien8.de [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id 2Abegj8iRGYn; Wed, 14 Jan 2026 15:47:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=alien8; t=1768405635; bh=xSyGH2S7hw1AUiS9jEfdC4Jr8F3HyJxMOuZ6mZOurSc=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=gDEI+zFP6Ss3OY2BMcgbNLN6U7b1rIDSoTpKUB2buPrrZIaCri12/AmAYJPCvFLam xVr8dN9vmC39iER+aqrDI6eEPdJs9jDu5SJm2HSujdKeX+WMVtFn7scxIyP391CrrZ uDxlfppV1co4BKRgvTr3mf4urvTob2ZO8gc3iC3oIYaA/Qi09Pnsyi1ohpiQKcdRdX IPStX4Mnb3FyoI8OHQxQ6SI1v1sXu3zihNxvpN2msC1FPV91G9Y7rVhbR9CTYPCwXd l3H2ncP4mMl8x7V57bLLQ+4C3Gy7P8BznsWOg+YaNBbMI1Eek8yCGfdw9PiFixOxeU 6fBFy2sbgx8riUtgBto4EnqAu8bybVK/QI37n5OjBb9RKLEl2rcZGJQuO3vkHaNZNe ZxBftFt8d3VDUfd7efGESykH4eyJP0nr2ANXZ/BxfOvGpqwrTKpumDKfmMXTuVwRgV 9A92b7etLcXP+ZyK2eFIs6RP5/1AYim6VJt8Ezr4xZgxUDtxW9W9YwEQs/naCDmuXw Jp1B5c5uZ2gkql++3Booc1daFCgLsXonLPu0VWNPJoHq//zGKX69DVD27I1Xv9c/ml dt8B+W4d2egZAZDv1WjRCMNkJqYVfVrMP38EX0VMmHl4mJG6Mn2JkpGXfwWSf6G+aC YxlOwbepQGXZpEMl2IfwwON0= Received: from zn.tnic (pd953023b.dip0.t-ipconnect.de [217.83.2.59]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature ECDSA (P-256) server-digest SHA256) (No client certificate requested) by mail.alien8.de (SuperMail on ZX Spectrum 128k) with UTF8SMTPSA id 1DC3E40E0028; Wed, 14 Jan 2026 15:47:03 +0000 (UTC) Date: Wed, 14 Jan 2026 16:46:56 +0100 From: Borislav Petkov To: Shenghao Yang Cc: x86@kernel.org, Jonathan Corbet , "Rafael J. Wysocki" , Len Brown , Thomas Gleixner , Ingo Molnar , Dave Hansen , "H. Peter Anvin" , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org Subject: Re: [PATCH] x86/acpi: Add acpi=spcr to use SPCR-provided default console Message-ID: <20260114154656.GDaWe6cFCruAGbJbhe@fat_crate.local> References: <20251228092222.130954-1-me@shenghaoyang.info> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20251228092222.130954-1-me@shenghaoyang.info> On Sun, Dec 28, 2025 at 05:22:22PM +0800, Shenghao Yang wrote: > Commit 0231d00082f6 ("ACPI: SPCR: Make SPCR available to x86") > made SPCR available as an earlycon option on x86 but did not add > it as a preferred console to avoid breaking existing setups - No one has noticed AFAICT since 2018 (this commit's date). Also: /* Do not enable ACPI SPCR console by default */ acpi_parse_spcr(earlycon_acpi_spcr_enable, false); Looks nicely conservative to me. > users have to round trip the dumped console options > ("SPCR: console: uart,io,0x3f8,115200") back via their > bootloader. I don't know what that means. > Let users opt in so serial console configuration can be made > automatic. Why? Text says: [X86] When used with no options the early console is determined by the ACPI SPCR table. But the code doesn't enable the SPCR console by default. I have no clue what this patch is trying to do. -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette