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Subject: Re: [RFC PATCH] do_exit(): panic() recursion detected
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     Jonathan Corbet <corbet@lwn.net>,
        Luis Chamberlain <mcgrof@kernel.org>,
        Kees Cook <keescook@chromium.org>,
        Iurii Zaikin <yzaikin@google.com>,
        "Paul E. McKenney" <paulmck@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Randy Dunlap <rdunlap@infradead.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Mauro Carvalho Chehab <mchehab+huawei@kernel.org>,
        Mike Kravetz <mike.kravetz@oracle.com>,
        "Guilherme G. Piccoli" <gpiccoli@canonical.com>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Kars Mulder <kerneldev@karsmulder.nl>,
        Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>,
        Kishon Vijay Abraham I <kishon@ti.com>,
        Arvind Sankar <nivedita@alum.mit.edu>,
        Joe Perches <joe@perches.com>,
        Rafael Aquini <aquini@redhat.com>,
        "Eric W. Biederman" <ebiederm@xmission.com>,
        Christian Brauner <christian.brauner@ubuntu.com>,
        Alexei Starovoitov <ast@kernel.org>,
        Davidlohr Bueso <dave@stgolabs.net>,
        Michel Lespinasse <walken@google.com>,
        Jann Horn <jannh@google.com>, chenqiwu <chenqiwu@xiaomi.com>,
        Minchan Kim <minchan@kernel.org>,
        Christophe Leroy <christophe.leroy@c-s.fr>,
        Vladimir Kondratiev <vladimir.kondratiev@intel.com>,
        linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-fsdevel@vger.kernel.org
References: <20201207124050.4016994-1-vladimir.kondratiev@linux.intel.com>
 <20201207125145.GM3040@hirez.programming.kicks-ass.net>
From:   Vladimir Kondratiev <vladimir.kondratiev@linux.intel.com>
Message-ID: <8056f890-0297-6fa9-c9a6-c9909e0f24af@linux.intel.com>
Date:   Mon, 7 Dec 2020 14:55:18 +0200
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We do panic on oops as well. We panic on anything that may point to 
system stability issues. I can't proof this code can't be reached 
without oops, so I want to panic here as well.

On 12/7/20 2:51 PM, Peter Zijlstra wrote:
> On Mon, Dec 07, 2020 at 02:40:49PM +0200, Vladimir Kondratiev wrote:
>> From: Vladimir Kondratiev <vladimir.kondratiev@intel.com>
>>
>> Recursive do_exit() is symptom of compromised kernel integrity.
>> For safety critical systems, it may be better to
>> panic() in this case to minimize risk.
> 
> You've not answered the previously posed question on why panic_on_oops
> isn't more suitable for your type of systems.
> 
>> Signed-off-by: Vladimir Kondratiev <vladimir.kondratiev@intel.com>
>> Change-Id: I42f45900a08c4282c511b05e9e6061360d07db60
> 
> This Change-ID crap doesn't belong in kernel patches.
>