From: Vivek Goyal <vgoyal@redhat.com>
To: David Rientjes <rientjes@google.com>
Cc: Prarit Bhargava <prarit@redhat.com>,
linux-kernel@vger.kernel.org, Jonathan Corbet <corbet@lwn.net>,
Andrew Morton <akpm@linux-foundation.org>,
Rusty Russell <rusty@rustcorp.com.au>,
"H. Peter Anvin" <hpa@zytor.com>, Andi Kleen <ak@linux.intel.com>,
Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>,
Fabian Frederick <fabf@skynet.be>,
isimatu.yasuaki@jp.fujitsu.com, jbaron@akamai.com,
linux-doc@vger.kernel.org, kexec@lists.infradead.org,
linux-api@vger.kernel.org
Subject: Re: [PATCH v8] kernel, add panic_on_warn
Date: Thu, 6 Nov 2014 17:07:31 -0500 [thread overview]
Message-ID: <20141106220731.GA13590@redhat.com> (raw)
In-Reply-To: <alpine.DEB.2.10.1411061352440.1526@chino.kir.corp.google.com>
On Thu, Nov 06, 2014 at 01:57:36PM -0800, David Rientjes wrote:
[..]
> You see that doing
>
> if (panic_on_warn) {
> panic_on_warn = 0;
> panic(...);
> }
>
> is racy, I hope. If two threads WARN() at the same time, then there's
> nothing preventing a double panic() because WARN() itself is not
> serialized against anything. So both the current comment and your
> suggested revision comment are bogus.
panic() is serialized on panic_lock. So I guess it is fine to hit WARN()
on multiple cpus. Do you see an issue there?
Thanks
Vivek
next prev parent reply other threads:[~2014-11-06 22:08 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
2014-11-05 21:59 ` David Rientjes
2014-11-06 13:10 ` Prarit Bhargava
2014-11-06 21:57 ` David Rientjes
2014-11-06 22:07 ` Vivek Goyal [this message]
2014-11-06 22:52 ` Prarit Bhargava
2014-11-07 10:15 ` David Rientjes
2014-11-07 11:05 ` Prarit Bhargava
2014-11-07 21:09 ` David Rientjes
2014-11-08 13:29 ` Prarit Bhargava
2014-11-06 22:51 ` Prarit Bhargava
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=20141106220731.GA13590@redhat.com \
--to=vgoyal@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=prarit@redhat.com \
--cc=rientjes@google.com \
--cc=rusty@rustcorp.com.au \
/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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox