From: Prarit Bhargava <prarit@redhat.com>
To: linux-kernel@vger.kernel.org, Andi Kleen <ak@linux.intel.com>,
Jonathan Corbet <corbet@lwn.net>,
kexec@lists.infradead.org, Rusty Russell <rusty@rustcorp.com.au>,
linux-doc@vger.kernel.org, jbaron@akamai.com,
Fabian Frederick <fabf@skynet.be>,
isimatu.yasuaki@jp.fujitsu.com, "H. Peter Anvin" <hpa@zytor.com>,
Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>,
Andrew Morton <akpm@linux-foundation.org>,
linux-api@vger.kernel.org, vgoyal@redhat.com
Subject: Re: [PATCH] kernel, add panic_on_warn
Date: Mon, 03 Nov 2014 08:32:42 -0500 [thread overview]
Message-ID: <545783FA.4050508@redhat.com> (raw)
In-Reply-To: <20141031015843.GW9743@dangermouse.emea.sgi.com>
On 10/30/2014 09:58 PM, Hedi Berriche wrote:
> On Thu, Oct 30, 2014 at 17:06 Prarit Bhargava wrote:
> | There have been several times where I have had to rebuild a kernel to
> | cause a panic when hitting a WARN() in the code in order to get a crash
> | dump from a system. Sometimes this is easy to do, other times (such as
> | in the case of a remote admin) it is not trivial to send new images to the
> | user.
> |
> | A much easier method would be a switch to change the WARN() over to a
> | panic. This makes debugging easier in that I can now test the actual
> | image the WARN() was seen on and I do not have to engage in remote
> | debugging.
>
> Do we want to leave it to usersspace[1] to ensure panic_on_warn is out
> of the way in when the kdump kernel boots? or would a self-contained
> approach be more preferable i.e. test whether we're a kdump kernel
> before bothering with panic_on_warn?
Hmm ... this is a good point. Vivek, do you have a preference? I'm willing to
code it either way. I should be able to put in a is_kdump_kernel() check
without any problems but I'm not sure if that is the right thing to do here.
P.
>
> Cheers,
> Hedi.
>
> [1] kexec-tools in the case of the boot param by filtering it out of the
> kdump kernel cmdline. In the case of sysctl.conf, it would depend on
> whether there are distros out there that include it in the kdump
> initrd.
>
_______________________________________________
kexec mailing list
kexec@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/kexec
WARNING: multiple messages have this Message-ID (diff)
From: Prarit Bhargava <prarit-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
To: linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
Andi Kleen <ak-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>,
Jonathan Corbet <corbet-T1hC0tSOHrs@public.gmane.org>,
kexec-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org,
Rusty Russell <rusty-8n+1lVoiYb80n/F98K4Iww@public.gmane.org>,
linux-doc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
jbaron-JqFfY2XvxFXQT0dZR+AlfA@public.gmane.org,
Fabian Frederick <fabf-AgBVmzD5pcezQB+pC5nmwQ@public.gmane.org>,
isimatu.yasuaki-+CUm20s59erQFUHtdCDX3A@public.gmane.org,
"H. Peter Anvin" <hpa-YMNOUZJC4hwAvxtiuMwx3w@public.gmane.org>,
Masami Hiramatsu
<masami.hiramatsu.pt-FCd8Q96Dh0JBDgjK7y7TUQ@public.gmane.org>,
Andrew Morton
<akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org>,
linux-api-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
vgoyal-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org
Subject: Re: [PATCH] kernel, add panic_on_warn
Date: Mon, 03 Nov 2014 08:32:42 -0500 [thread overview]
Message-ID: <545783FA.4050508@redhat.com> (raw)
In-Reply-To: <20141031015843.GW9743-2aXy8kx9jd5qWu+OMeiFJmRHvnxUvMa2@public.gmane.org>
On 10/30/2014 09:58 PM, Hedi Berriche wrote:
> On Thu, Oct 30, 2014 at 17:06 Prarit Bhargava wrote:
> | There have been several times where I have had to rebuild a kernel to
> | cause a panic when hitting a WARN() in the code in order to get a crash
> | dump from a system. Sometimes this is easy to do, other times (such as
> | in the case of a remote admin) it is not trivial to send new images to the
> | user.
> |
> | A much easier method would be a switch to change the WARN() over to a
> | panic. This makes debugging easier in that I can now test the actual
> | image the WARN() was seen on and I do not have to engage in remote
> | debugging.
>
> Do we want to leave it to usersspace[1] to ensure panic_on_warn is out
> of the way in when the kdump kernel boots? or would a self-contained
> approach be more preferable i.e. test whether we're a kdump kernel
> before bothering with panic_on_warn?
Hmm ... this is a good point. Vivek, do you have a preference? I'm willing to
code it either way. I should be able to put in a is_kdump_kernel() check
without any problems but I'm not sure if that is the right thing to do here.
P.
>
> Cheers,
> Hedi.
>
> [1] kexec-tools in the case of the boot param by filtering it out of the
> kdump kernel cmdline. In the case of sysctl.conf, it would depend on
> whether there are distros out there that include it in the kdump
> initrd.
>
WARNING: multiple messages have this Message-ID (diff)
From: Prarit Bhargava <prarit@redhat.com>
To: linux-kernel@vger.kernel.org, Andi Kleen <ak@linux.intel.com>,
Jonathan Corbet <corbet@lwn.net>,
kexec@lists.infradead.org, Rusty Russell <rusty@rustcorp.com.au>,
linux-doc@vger.kernel.org, jbaron@akamai.com,
Fabian Frederick <fabf@skynet.be>,
isimatu.yasuaki@jp.fujitsu.com, "H. Peter Anvin" <hpa@zytor.com>,
Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>,
Andrew Morton <akpm@linux-foundation.org>,
linux-api@vger.kernel.org, vgoyal@redhat.com
Subject: Re: [PATCH] kernel, add panic_on_warn
Date: Mon, 03 Nov 2014 08:32:42 -0500 [thread overview]
Message-ID: <545783FA.4050508@redhat.com> (raw)
In-Reply-To: <20141031015843.GW9743@dangermouse.emea.sgi.com>
On 10/30/2014 09:58 PM, Hedi Berriche wrote:
> On Thu, Oct 30, 2014 at 17:06 Prarit Bhargava wrote:
> | There have been several times where I have had to rebuild a kernel to
> | cause a panic when hitting a WARN() in the code in order to get a crash
> | dump from a system. Sometimes this is easy to do, other times (such as
> | in the case of a remote admin) it is not trivial to send new images to the
> | user.
> |
> | A much easier method would be a switch to change the WARN() over to a
> | panic. This makes debugging easier in that I can now test the actual
> | image the WARN() was seen on and I do not have to engage in remote
> | debugging.
>
> Do we want to leave it to usersspace[1] to ensure panic_on_warn is out
> of the way in when the kdump kernel boots? or would a self-contained
> approach be more preferable i.e. test whether we're a kdump kernel
> before bothering with panic_on_warn?
Hmm ... this is a good point. Vivek, do you have a preference? I'm willing to
code it either way. I should be able to put in a is_kdump_kernel() check
without any problems but I'm not sure if that is the right thing to do here.
P.
>
> Cheers,
> Hedi.
>
> [1] kexec-tools in the case of the boot param by filtering it out of the
> kdump kernel cmdline. In the case of sysctl.conf, it would depend on
> whether there are distros out there that include it in the kdump
> initrd.
>
next prev parent reply other threads:[~2014-11-03 13:33 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-10-30 17:03 [PATCH] kernel, add panic_on_warn Prarit Bhargava
2014-10-30 17:03 ` Prarit Bhargava
2014-10-30 17:24 ` H. Peter Anvin
2014-10-30 17:24 ` H. Peter Anvin
2014-10-30 17:24 ` H. Peter Anvin
2014-10-31 1:58 ` Hedi Berriche
2014-10-31 1:58 ` Hedi Berriche
2014-10-31 1:58 ` Hedi Berriche
2014-11-03 13:32 ` Prarit Bhargava [this message]
2014-11-03 13:32 ` Prarit Bhargava
2014-11-03 13:32 ` Prarit Bhargava
2014-11-03 15:18 ` Vivek Goyal
2014-11-03 15:18 ` Vivek Goyal
2014-11-03 15:18 ` Vivek Goyal
-- strict thread matches above, loose matches on Subject: below --
2014-11-04 15:41 Prarit Bhargava
2014-11-04 15:41 ` Prarit Bhargava
2014-11-04 15:41 ` Prarit Bhargava
2014-11-05 4:27 ` WANG Chao
2014-11-05 4:27 ` WANG Chao
2014-11-05 4:55 ` Yasuaki Ishimatsu
2014-11-05 4:55 ` Yasuaki Ishimatsu
2014-11-05 4:55 ` Yasuaki Ishimatsu
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=545783FA.4050508@redhat.com \
--to=prarit@redhat.com \
--cc=ak@linux.intel.com \
--cc=akpm@linux-foundation.org \
--cc=corbet@lwn.net \
--cc=fabf@skynet.be \
--cc=hpa@zytor.com \
--cc=isimatu.yasuaki@jp.fujitsu.com \
--cc=jbaron@akamai.com \
--cc=kexec@lists.infradead.org \
--cc=linux-api@vger.kernel.org \
--cc=linux-doc@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=masami.hiramatsu.pt@hitachi.com \
--cc=rusty@rustcorp.com.au \
--cc=vgoyal@redhat.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.