From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx2.suse.de ([195.135.220.15]:53600 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725843AbeKUAJW (ORCPT ); Tue, 20 Nov 2018 19:09:22 -0500 Date: Tue, 20 Nov 2018 14:40:07 +0100 From: Jean Delvare Subject: Backed up kernels Message-ID: <20181120144007.016e4998@endymion> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kbuild-owner@vger.kernel.org List-ID: To: Masahiro Yamada , Michal Marek Cc: linux-kbuild@vger.kernel.org, Martin Wilck , LKML Hi Masahiro, Michal, When I run "make install", if a kernel by the same version number + flavor string already exists, a backup is created with ".old" appended. Over time, this adds many entries to my boot menu, makes some package updates take much longer (e.g. when all initrds must be regenerated), and ultimately confuses grub2, which fails to find the matching modules directory under /lib/modules. You could argue that grub2 could be fixed to find the right modules directory, but in fact there is no guarantee that the modules built for the new kernel are fully compatible with the old kernel. Keeping a backup copy of the old modules is also not possible, because both kernels have the same $(uname -r) and therefore the modules of both kernels must live under the same /lib/modules/$(uname -r), which collides. Given that, is there really any practical value in saving a backup of old kernels? I'm doing kernel development for 15 years and I can't remember ever booting one of these ".old" kernels. If my latest development kernel doesn't work for any reason, I will just boot back to the distribution kernel. Therefore I am asking, can we change "make install" so that it does NOT create a backup copy of an existing kernel? Thanks, -- Jean Delvare SUSE L3 Support