Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Date:   Thu, 30 Sep 2021 11:20:34 -0700
From:   Kees Cook <keescook@chromium.org>
To:     Alexander Popov <alex.popov@linux.com>
Cc:     Dave Hansen <dave.hansen@intel.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Jonathan Corbet <corbet@lwn.net>,
        Paul McKenney <paulmck@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Joerg Roedel <jroedel@suse.de>,
        Maciej Rozycki <macro@orcam.me.uk>,
        Muchun Song <songmuchun@bytedance.com>,
        Viresh Kumar <viresh.kumar@linaro.org>,
        Robin Murphy <robin.murphy@arm.com>,
        Randy Dunlap <rdunlap@infradead.org>,
        Lu Baolu <baolu.lu@linux.intel.com>,
        Petr Mladek <pmladek@suse.com>,
        Luis Chamberlain <mcgrof@kernel.org>, Wei Liu <wl@xen.org>,
        John Ogness <john.ogness@linutronix.de>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Alexey Kardashevskiy <aik@ozlabs.ru>,
        Christophe Leroy <christophe.leroy@csgroup.eu>,
        Jann Horn <jannh@google.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Mark Rutland <mark.rutland@arm.com>,
        Andy Lutomirski <luto@kernel.org>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Steven Rostedt <rostedt@goodmis.org>,
        Will Deacon <will.deacon@arm.com>,
        David S Miller <davem@davemloft.net>,
        Borislav Petkov <bp@alien8.de>,
        kernel-hardening@lists.openwall.com,
        linux-hardening@vger.kernel.org, linux-doc@vger.kernel.org,
        linux-kernel@vger.kernel.org, notify@kernel.org
Subject: Re: [PATCH] Introduce the pkill_on_warn boot parameter
Message-ID: <202109301120.B7B8F3F8A@keescook>
References: <20210929185823.499268-1-alex.popov@linux.com>
 <323d0784-249d-7fef-6c60-e8426d35b083@intel.com>
 <202109291229.C64A1D9D@keescook>
 <cf6ada34-9854-b7ad-f671-52186da5abd0@linux.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <cf6ada34-9854-b7ad-f671-52186da5abd0@linux.com>
Precedence: bulk

On Thu, Sep 30, 2021 at 04:55:37PM +0300, Alexander Popov wrote:
> The kernel can hit warning and omit calling __warn() that prints the message.
> But pkill_on_warn action should be taken each time.
> 
> As I can understand now, include/asm-generic/bug.h defines three warning
> implementations:
>  1. CONFIG_BUG=y and the arch provides __WARN_FLAGS. In that case pkill_on_warn
> should be checked in report_bug() that you mention.
>  2. CONFIG_BUG=y and the arch doesn't have __WARN_FLAGS. In that case
> pkill_on_warn should be checked in warn_slowpath_fmt().
>  3. CONFIG_BUG is not set. In that case pkill_on_warn should not be considered.
> 
> Please, correct me if needed.

That looks correct to me, yes.

-- 
Kees Cook