From: Prarit Bhargava <prarit-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
To: David Rientjes <rientjes-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
Cc: Andi Kleen <ak-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>,
Jonathan Corbet <corbet-T1hC0tSOHrs@public.gmane.org>,
jbaron-JqFfY2XvxFXQT0dZR+AlfA@public.gmane.org,
kexec-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org,
Rusty Russell <rusty-8n+1lVoiYb80n/F98K4Iww@public.gmane.org>,
linux-doc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
linux-kernel-u79uwXL29TY76Z2rM5mHXA@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,
Vivek Goyal <vgoyal-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
Subject: Re: [PATCH v8] kernel, add panic_on_warn
Date: Sat, 08 Nov 2014 08:29:21 -0500 [thread overview]
Message-ID: <545E1AB1.9030001@redhat.com> (raw)
In-Reply-To: <alpine.DEB.2.10.1411071306370.12192-X6Q0R45D7oAcqpCFd4KODRPsWskHk0ljAL8bYrjMMd8@public.gmane.org>
On 11/07/2014 04:09 PM, David Rientjes wrote:
> On Fri, 7 Nov 2014, Prarit Bhargava wrote:
>
>> There very much is. Consider a thread that hits a WARN() and then panics. Then
>> somewhere in the panic code the thread hits another WARN() ... and then panics
>> again. Previously this would have caused the system to "finish" panick'ing.
>> Now it makes the system hang.
>>
>
> Then we're back to square one which is what is obviously the intent of
> your patch and the comment that goes along with it:
My original reply pointed out that the comment was wrong.
we want to clear
> panic_on_warn once and not allow multiple panic().
On _this_ thread. The multiple panic across threads cannot occur.
So why not just add
> the necessary synchronization to make sure that happens when WARN()
> happens on two cpus simultaneously?
See above.
P.
>
next prev parent reply other threads:[~2014-11-08 13:29 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-11-05 11:42 [PATCH v8] kernel, add panic_on_warn Prarit Bhargava
[not found] ` <1415187736-16242-1-git-send-email-prarit-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
2014-11-05 21:59 ` David Rientjes
[not found] ` <alpine.DEB.2.10.1411051357050.31575-X6Q0R45D7oAcqpCFd4KODRPsWskHk0ljAL8bYrjMMd8@public.gmane.org>
2014-11-06 13:10 ` Prarit Bhargava
[not found] ` <545B733C.6080903-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
2014-11-06 21:57 ` David Rientjes
[not found] ` <alpine.DEB.2.10.1411061352440.1526-X6Q0R45D7oAcqpCFd4KODRPsWskHk0ljAL8bYrjMMd8@public.gmane.org>
2014-11-06 22:07 ` Vivek Goyal
[not found] ` <20141106220731.GA13590-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
2014-11-06 22:52 ` Prarit Bhargava
2014-11-07 10:15 ` David Rientjes
[not found] ` <alpine.DEB.2.10.1411070214220.32405-X6Q0R45D7oAcqpCFd4KODRPsWskHk0ljAL8bYrjMMd8@public.gmane.org>
2014-11-07 11:05 ` Prarit Bhargava
2014-11-07 21:09 ` David Rientjes
[not found] ` <alpine.DEB.2.10.1411071306370.12192-X6Q0R45D7oAcqpCFd4KODRPsWskHk0ljAL8bYrjMMd8@public.gmane.org>
2014-11-08 13:29 ` Prarit Bhargava [this message]
2014-11-06 22:51 ` Prarit Bhargava
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