From nobody Sun Sep 14 03:24:12 2025 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 6357BC54EAA for ; Thu, 26 Jan 2023 22:54:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233079AbjAZWyr (ORCPT ); Thu, 26 Jan 2023 17:54:47 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53048 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233054AbjAZWye (ORCPT ); Thu, 26 Jan 2023 17:54:34 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3A8AA7AA8; Thu, 26 Jan 2023 14:54:30 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id DF00CB81C5E; Thu, 26 Jan 2023 22:54:28 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 66A2AC433D2; Thu, 26 Jan 2023 22:54:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1674773667; bh=A3hJdPRvqNFhvIc040dVHaOyGrcDglgpuQvKqvik2wo=; h=From:To:Cc:Subject:Date:From; b=otj/1MSrw0yysqoNbGEuXeqQMozGhrSqIB9eZlrYgbsXb4hIJbrZMzmFR7/RnYlIQ u5V34KfTKJG9ucf79p0W1+TlGqcCdMG11D1PJxtMXKq3CVYLrD/jxEyVpzZq736mSn D240LUTOUZRvQW1B4b15LN0zrhZoVckt9GfvmDGiIvBCO2AIrqZZOoLIuyF6Cri+8K phI/LbAbDN9O2VSUNn8vSqwMpux/0Fo48+4Gk80UfKowbTCeDINM1rwX7PA3TWGMoz uLixwzi5EQJL6KJSG8Kl6wJ6p0mjzZ/mjg99bBrEaEc6CgkgIi+gQ2K9hdgpf9Ilkw BB5Z8mFI1EN9A== From: Bjorn Helgaas To: Jonathan Corbet Cc: Matthew Wilcox , Randy Dunlap , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, Bjorn Helgaas Subject: [PATCH v2] printk: Document that CONFIG_BOOT_PRINTK_DELAY required for boot_delay= Date: Thu, 26 Jan 2023 16:54:20 -0600 Message-Id: <20230126225420.1320276-1-helgaas@kernel.org> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Bjorn Helgaas Document the fact that CONFIG_BOOT_PRINTK_DELAY must be enabled for the "boot_delay" kernel parameter to work. Also mention that "lpj=3D" may be necessary. Signed-off-by: Bjorn Helgaas Reviewed-by: Randy Dunlap --- Changes from v1 (https://lore.kernel.org/all/20230123180440.901793-1-helgaa= s@kernel.org/): - Clarify use of "lpj=3D". Reword consequences of delay larger than 10000. Documentation/admin-guide/kernel-parameters.txt | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentatio= n/admin-guide/kernel-parameters.txt index 6cfa6e3996cf..814e58487239 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -480,8 +480,10 @@ See Documentation/block/cmdline-partition.rst =20 boot_delay=3D Milliseconds to delay each printk during boot. - Values larger than 10 seconds (10000) are changed to - no delay (0). + Only works if CONFIG_BOOT_PRINTK_DELAY is enabled, + and you may also have to specify "lpj=3D". Boot_delay + values larger than 10 seconds (10000) are assumed + erroneous and ignored. Format: integer =20 bootconfig [KNL] --=20 2.25.1