From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mx1.redhat.com ([209.132.183.28]) by bombadil.infradead.org with esmtps (Exim 4.85_2 #1 (Red Hat Linux)) id 1bNhNQ-0007jm-DQ for kexec@lists.infradead.org; Thu, 14 Jul 2016 14:12:32 +0000 Date: Thu, 14 Jul 2016 22:12:05 +0800 From: Baoquan He Subject: Re: [PATCH] kexec: Add option to fallback to old kexec syscall when kexec file based syscall failed Message-ID: <20160714141205.GB9366@x1.redhat.com> References: <1468485911-21427-1-git-send-email-jlee@suse.com> <20160714095124.GA9366@x1.redhat.com> <20160714103510.GX11998@linux-rxt1.site> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20160714103510.GX11998@linux-rxt1.site> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "kexec" Errors-To: kexec-bounces+dwmw2=infradead.org@lists.infradead.org To: joeyli Cc: Simon Horman , "Lee, Chun-Yi" , kexec@lists.infradead.org, Vivek Goyal , Petr Tesarik On 07/14/16 at 06:35pm, joeyli wrote: > Hi Baoquan, > > Thanks for your response! > > On Thu, Jul 14, 2016 at 05:51:24PM +0800, Baoquan He wrote: > > On 07/14/16 at 04:45pm, Lee, Chun-Yi wrote: > > > This patch adds a new "--fallback-kexec" option to give a chance to > > > fallback to old kexec syscall when file based kexec syscall operation > > > failed. > > > > > > This option works with --kexec-file-syscall to provide more flexible > > > way to adapt to different kernels that those kernels built with > > > different kexec syscall config or have different verification policy. > > > > Usually distribuition system uses script to build a framework to > > connect the kexec/kdump, makedumpfile utility chain. This can make user > > execute a very simple script command to implement kexec load or kexec > > jumping job. In this case script can do what you are trying to do. > > > > Yes, the fallback function can be implemented by script. But a new kexec > option is useful to the distro that it may not provides help scripts to > user. > > > Besides, have you actually met that kexec-file failed but old kexec > > syscall works? I mean how did you test it? I am wondering when it will > > happen. > > > > Thanks > > Baoquan > > > I understand, thanks for telling, Joey Lee. However it seems not very necessary to me. So leave this to other people, see if you can get support and an Acked-by. Thanks Baoquan > The currently mainline kernel allows to set CONFIG_KEXEC or CONFIG_KEXEC_FILE > individual. So if kexec found that the file based kexec syscall isn't > available then this is a case to fallback to old kexec. > > Another case is when KEXEC_VERIFY_SIG is set, The fallback function is more > convenient to user to build his own kernel for using or testing. The kexec > tool can try old syscall when verification failed. _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec