From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753413AbeARB5a (ORCPT ); Wed, 17 Jan 2018 20:57:30 -0500 Received: from mx1.redhat.com ([209.132.183.28]:58490 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752062AbeARB53 (ORCPT ); Wed, 17 Jan 2018 20:57:29 -0500 Date: Thu, 18 Jan 2018 09:57:21 +0800 From: Dave Young To: Petr Mladek Cc: sergey.senozhatsky@gmail.com, rostedt@goodmis.org, linux-kernel@vger.kernel.org, akpm@linux-foundation.org, kexec@lists.infradead.org Subject: Re: [PATCH] print kdump kernel loaded status in stack dump Message-ID: <20180118015721.GC1812@dhcp-128-65.nay.redhat.com> References: <20180117045057.GA4994@dhcp-128-65.nay.redhat.com> <20180117085734.jx77p3brjykk3ude@pathway.suse.cz> <20180117123244.GA1503@dhcp-128-65.nay.redhat.com> <20180117134217.6gjr5ep3g2ns2v3w@pathway.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180117134217.6gjr5ep3g2ns2v3w@pathway.suse.cz> User-Agent: Mutt/1.9.1 (2017-09-22) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/17/18 at 02:42pm, Petr Mladek wrote: > On Wed 2018-01-17 20:32:44, Dave Young wrote: > > Hi, > > > > Thanks for your comments. > > On 01/17/18 at 09:57am, Petr Mladek wrote: > > > On Wed 2018-01-17 12:50:57, Dave Young wrote: > > > > It is useful to print kdump kernel loaded status in dump_stack() > > > > especially when panic happens so that we can differenciate > > > > kdump kernel early hang and a normal panic in a bug report. > > > > > > > > Signed-off-by: Dave Young > > > > --- > > > > kernel/printk/printk.c | 3 +++ > > > > 1 file changed, 3 insertions(+) > > > > > > > > --- linux-x86.orig/kernel/printk/printk.c > > > > +++ linux-x86/kernel/printk/printk.c > > > > @@ -48,6 +48,7 @@ > > > > #include > > > > #include > > > > #include > > > > +#include > > > > > > > > #include > > > > #include > > > > @@ -3127,6 +3128,8 @@ void dump_stack_print_info(const char *l > > > > if (dump_stack_arch_desc_str[0] != '\0') > > > > printk("%sHardware name: %s\n", > > > > log_lvl, dump_stack_arch_desc_str); > > > > + if (kexec_crash_loaded()) > > > > + printk("%skdump kernel loaded\n", log_lvl); > > > > > > IMHO, it would be better to do it like for the workqueues. > > > I mean to call printk_kexec_info(log_lv1, current) here > > > that would be impletemented in kexec sources. > > > Then it could be maintained by kexec people. > > > > > > Anyway, I wonder if the info about kexec_crash_loaded() is > > > enough. I am not much familiar with kexec. AFAIK, > > > the image might be loaded long time before it > > > is acutally used. > > > > kexec_crash_loaded is enough, we only care if kdump kernel being > > loaded or not, nothing else, no matter how long it has been loaded. > > In Fedora/RHEL a kdump service takes care of loading the kernel but > > it runs after networking is ready. If people want to save > > the vmcore to nfs/ssh then we need detect network and build the > > initramfs. In the nfs/ssh case if some networking code panicked it > > is possible that kdump service has not started, but sometimes bug > > can not be easily reproduced thus nobody can know if kdump is active > > or not. > > I see. > > > Since kexec_crash_loaded() is already in kexec souce code, and it > > is the only thing need to know, do you think it is really necessary > > to add a printk_kexec_info()? I can do it if you strongly suggest > > to do so. > > No, the original approach is fine if it is really that simple ;-) > > > > > > > Finally, the style of the other lines is: > > > > > > Name: details > > > > > > I would suggest to print something like: > > > > > > Kexec: details > > > > > > , where the details might be whether the image is loaded, > > > whether the loaded kernel is being executed, and > > > other kexec-related flags. > > > > Will do, it can be something like: > > Kexec: kdump kernel loaded > > Looks good to me. With this message, I could give this > patch even > > Reviewed-by: Petr Mladek > > I could update the string when pushing into printk.git. > I am just going to wait a bit for more feedback if any. Cool, thank you! > > Best Regards, > Petr Thanks Dave 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 4.89 #1 (Red Hat Linux)) id 1ebzSV-00059l-Ia for kexec@lists.infradead.org; Thu, 18 Jan 2018 01:57:41 +0000 Date: Thu, 18 Jan 2018 09:57:21 +0800 From: Dave Young Subject: Re: [PATCH] print kdump kernel loaded status in stack dump Message-ID: <20180118015721.GC1812@dhcp-128-65.nay.redhat.com> References: <20180117045057.GA4994@dhcp-128-65.nay.redhat.com> <20180117085734.jx77p3brjykk3ude@pathway.suse.cz> <20180117123244.GA1503@dhcp-128-65.nay.redhat.com> <20180117134217.6gjr5ep3g2ns2v3w@pathway.suse.cz> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20180117134217.6gjr5ep3g2ns2v3w@pathway.suse.cz> 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: Petr Mladek Cc: sergey.senozhatsky@gmail.com, akpm@linux-foundation.org, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, rostedt@goodmis.org On 01/17/18 at 02:42pm, Petr Mladek wrote: > On Wed 2018-01-17 20:32:44, Dave Young wrote: > > Hi, > > > > Thanks for your comments. > > On 01/17/18 at 09:57am, Petr Mladek wrote: > > > On Wed 2018-01-17 12:50:57, Dave Young wrote: > > > > It is useful to print kdump kernel loaded status in dump_stack() > > > > especially when panic happens so that we can differenciate > > > > kdump kernel early hang and a normal panic in a bug report. > > > > > > > > Signed-off-by: Dave Young > > > > --- > > > > kernel/printk/printk.c | 3 +++ > > > > 1 file changed, 3 insertions(+) > > > > > > > > --- linux-x86.orig/kernel/printk/printk.c > > > > +++ linux-x86/kernel/printk/printk.c > > > > @@ -48,6 +48,7 @@ > > > > #include > > > > #include > > > > #include > > > > +#include > > > > > > > > #include > > > > #include > > > > @@ -3127,6 +3128,8 @@ void dump_stack_print_info(const char *l > > > > if (dump_stack_arch_desc_str[0] != '\0') > > > > printk("%sHardware name: %s\n", > > > > log_lvl, dump_stack_arch_desc_str); > > > > + if (kexec_crash_loaded()) > > > > + printk("%skdump kernel loaded\n", log_lvl); > > > > > > IMHO, it would be better to do it like for the workqueues. > > > I mean to call printk_kexec_info(log_lv1, current) here > > > that would be impletemented in kexec sources. > > > Then it could be maintained by kexec people. > > > > > > Anyway, I wonder if the info about kexec_crash_loaded() is > > > enough. I am not much familiar with kexec. AFAIK, > > > the image might be loaded long time before it > > > is acutally used. > > > > kexec_crash_loaded is enough, we only care if kdump kernel being > > loaded or not, nothing else, no matter how long it has been loaded. > > In Fedora/RHEL a kdump service takes care of loading the kernel but > > it runs after networking is ready. If people want to save > > the vmcore to nfs/ssh then we need detect network and build the > > initramfs. In the nfs/ssh case if some networking code panicked it > > is possible that kdump service has not started, but sometimes bug > > can not be easily reproduced thus nobody can know if kdump is active > > or not. > > I see. > > > Since kexec_crash_loaded() is already in kexec souce code, and it > > is the only thing need to know, do you think it is really necessary > > to add a printk_kexec_info()? I can do it if you strongly suggest > > to do so. > > No, the original approach is fine if it is really that simple ;-) > > > > > > > Finally, the style of the other lines is: > > > > > > Name: details > > > > > > I would suggest to print something like: > > > > > > Kexec: details > > > > > > , where the details might be whether the image is loaded, > > > whether the loaded kernel is being executed, and > > > other kexec-related flags. > > > > Will do, it can be something like: > > Kexec: kdump kernel loaded > > Looks good to me. With this message, I could give this > patch even > > Reviewed-by: Petr Mladek > > I could update the string when pushing into printk.git. > I am just going to wait a bit for more feedback if any. Cool, thank you! > > Best Regards, > Petr Thanks Dave _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec