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 X-Spam-Level: X-Spam-Status: No, score=-3.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4881AC433C1 for ; Tue, 23 Mar 2021 01:17:52 +0000 (UTC) Received: from shelob.surriel.com (shelob.surriel.com [96.67.55.147]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id CA03061934 for ; Tue, 23 Mar 2021 01:17:51 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CA03061934 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=vt.edu Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernelnewbies-bounces@kernelnewbies.org Received: from localhost ([::1] helo=shelob.surriel.com) by shelob.surriel.com with esmtp (Exim 4.94) (envelope-from ) id 1lOVfc-0008DE-2I; Mon, 22 Mar 2021 21:17:20 -0400 Received: from mail-qt1-x836.google.com ([2607:f8b0:4864:20::836]) by shelob.surriel.com with esmtps (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (Exim 4.94) (envelope-from ) id 1lOVfZ-0008D6-Ru for kernelnewbies@kernelnewbies.org; Mon, 22 Mar 2021 21:17:18 -0400 Received: by mail-qt1-x836.google.com with SMTP id l13so13836849qtu.9 for ; Mon, 22 Mar 2021 18:17:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=vt-edu.20150623.gappssmtp.com; s=20150623; h=sender:from:to:cc:subject:in-reply-to:references:mime-version :content-transfer-encoding:date:message-id; bh=b9zWvhN2AsL6eDPmmfa9EF+sucPhmAE9gLLQrLaGDfc=; b=c9y2VUxeNtzTz6XQgcvWmjhkitscJAQ8OS7Tz+eJ1ziuh6JldicKd+x5kvwQf35CwP 66xVwuizf0SSejkEQsRz0ajjlj1uoPdE2YUERPwOtJHwnmoJSW6U+rcjH7Ho2SLLNWva OrFwXVWvHD/I8eQ9ceHsdS+bKQDGedzhD0jcWaK9KG8zQpX41PUqVNVovHlo9/JVmi7P aLW1WZqUIfJsvz2BbnbrmUSmtKvZGfodd63usWoKk3207xh1O0DqbONUKWFagYvMEQ38 foFxVPWqd7gCMNwG+K40JKxgG8ECQ5/8l94liIqL3nmH/AJD0nm5NmIyypahBFm+OQCs 71Tg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:from:to:cc:subject:in-reply-to:references :mime-version:content-transfer-encoding:date:message-id; bh=b9zWvhN2AsL6eDPmmfa9EF+sucPhmAE9gLLQrLaGDfc=; b=W4rmoWzX8KswB6/Re5SuXIncqAT6yqofgB62dJMmycBafXQmWyDAZ/wnUAVzuppyFE 42Wen7pAThWYt/MPFCLwgiaXDeqTUaPgB6OKWxnWbqhsutp+xU+Sh/LHZwQl01B3uKNw IzN4EG9tX2n/Fzqsl8VUZszVOeKPfKxuVXILuvaAlQdKwkSMsJzKOhSIsmKQK5e4MGKG DtZQdXncGW/cc6lG5xgkvcN0MEc4DOMtUXMEDRSEwJgXKe52rcQS3k834Yvl1e55hSjH OCfk0l85/Uj+b5dqHv6wcm45gYAJNqg/RnLEV/OcScHy1iI9Vf4RfhstObkQfHSqZ22J Pkbw== X-Gm-Message-State: AOAM530OD7GZvng0AguL/ObeaiTzQ+xsBiz7pyy3+8Be21sJxU1Ot3/K QF93n0NhNNJoYBaunszfP+Co1A== X-Google-Smtp-Source: ABdhPJwdFB2qKJ7JkCVYxce5sunFYnjtZiZTHNdvZdYzlkTdNLfb2Dv22QgFbfiEx+e4i1g+hW494g== X-Received: by 2002:ac8:4c90:: with SMTP id j16mr2462773qtv.223.1616462235106; Mon, 22 Mar 2021 18:17:15 -0700 (PDT) Received: from turing-police ([2601:5c0:c380:d61::359]) by smtp.gmail.com with ESMTPSA id g14sm12245109qkm.98.2021.03.22.18.17.14 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 22 Mar 2021 18:17:14 -0700 (PDT) From: "Valdis Kl=?utf-8?Q?=c4=93?=tnieks" X-Google-Original-From: "Valdis Kl=?utf-8?Q?=c4=93?=tnieks" X-Mailer: exmh version 2.9.0 11/07/2018 with nmh-1.7+dev To: Gidi Gal Subject: Re: How to switch between installed kernel and developed kernel In-Reply-To: References: <87zgyvtkd8.fsf@miraculix.mork.no> Mime-Version: 1.0 Date: Mon, 22 Mar 2021 21:17:13 -0400 Message-ID: <323555.1616462233@turing-police> Cc: Aruna Hewapathirane , kernelnewbies@kernelnewbies.org X-BeenThere: kernelnewbies@kernelnewbies.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Learn about the Linux kernel List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============7272687826536457598==" Errors-To: kernelnewbies-bounces@kernelnewbies.org --===============7272687826536457598== Content-Type: multipart/signed; boundary="==_Exmh_1616462233_29981P"; micalg=pgp-sha1; protocol="application/pgp-signature" Content-Transfer-Encoding: 7bit --==_Exmh_1616462233_29981P Content-Type: text/plain; charset=us-ascii On Tue, 23 Mar 2021 00:01:22 +0200, Gidi Gal said: > Many thanks for your reply, Aruna. Is there a way to remove the installed > '5.12.0-rc3-GIDI_DEV+' kernel ? A reverse command for the 'sudo make > modules_install install' command ? I found this link which explains how to > do it manually ( > https://www.cyberciti.biz/faq/debian-redhat-linux-delete-kernel-command/), > I wonder if there is a safer way. I can't speak for Debian, but I've used both the RedHat rpm method and just using the 'rm' command for self-bullt kernels since the 2.5.47 kernel or so (Egads, that was November 2002). As long as you follow the directions, you should be OK. 'rm' can get dangerous if you get over-exuberant with using '*' characters, but you already knew that, right? :) And if you followed my recommendation and back up /boot, you'll be all set to restore whatever you mess up. The running kernel will work just fine as long as you don't reboot. And unless you did 'rm /boot/*', you should have at least one usable kernel left... Seriously - if you're not comfortable with that level of sysadmin procedures, maybe you shouldn't be a kernel hacker... there is always the possibility of something you didn't know about trashing your system. See 5.12.0-rc1-dontuse for a nasty bug with file-backed swap that would stomp all over a section of your filesystem, and there was an ext[34] (can't remember anymore) bug during 2.5 that would trash the filesystem when you *unmounted* it. So you could boot the new kernel for testing, shutdown and boot the older version, and find it won't boot and be blaming the older version until we figured out what was happening. :) But seriously - if you have a good backup of the system, and an bootable external image that you can use for rescue, there's not much a kernel screw-up can do to permanently lose date. Of course, WIndows Update is at that same level of reliability, so "knowing how to recover a trashed system" is an important skill no matter what OS you run :) --==_Exmh_1616462233_29981P Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Comment: Exmh version 2.9.0 11/07/2018 iQIVAwUBYFlBmQdmEQWDXROgAQLzOg/5AV2wjwXQsGMPTG3lUobyERi36qQCJ7V/ 5FBmlWjCUJzoYssVwWinxpQaTq218BmJtGxH1aifHAGCzAOk/5+/tBxmc5jV+wxw KbJpKFS0IsS28taQQD5B3BPDYvLels32jy2PTR6yFQou8r5YILe9wRS2e31rneE/ KxpaaevWCWt5bi11kc7nGYqFbmeFBFzxesK3U0OfGFbPM15gzf96XPrHlTJ9qHOH 8tWUzVUkvSLKz6Zx/Dd33eekxFhjtMiHkJoWreosrahv6zYmFTGx9JvDFy/+0Hf+ ZI7lYLxLFTAE3j6eRnWOsieR2cDkGvalUA98ku+ElV4c16TL29ZmKKHGGll3sp+X ZbGh1A7MTh5mxbcYy++nqxai/ROx9036tiFx12K/uPTPbn8s9bVcs1w2T+YGuEl+ AAqzOq1fCnRc9h+Nhxz8d0DKFbfCjy9dqTlCL+LrmY2iIDVI3l0i3qTE3HJDUlfd R0BFjplnZT+fKPhAKxS6oCwmSU+XwjdhRB5M4neDjAH6GLwMvWGSS5miBXQenQLq 38541kFqiT1YCfPSXFiYqWOYqCOflj9D5N62qIMsuloCbWYG2vshRTEji+6NwcrH rgVo3LkkJdAmqFmIA2IGFYwaK6XcDAb1WVn2+O7L25FPqZax/0W00tPOj1xSb9m5 zToUqj46Ddg= =AJow -----END PGP SIGNATURE----- --==_Exmh_1616462233_29981P-- --===============7272687826536457598== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies --===============7272687826536457598==--