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[198.145.64.163]) by smtp.gmail.com with ESMTPSA id g18sm33078pfq.146.2020.05.26.09.15.05 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 26 May 2020 09:15:06 -0700 (PDT) Date: Tue, 26 May 2020 09:15:04 -0700 From: Kees Cook To: Greg KH Cc: Andi Kleen , x86@kernel.org, linux-kernel@vger.kernel.org, sashal@kernel.org, Andi Kleen , stable@vger.kernel.org Subject: Re: [PATCH v1] x86: Pin cr4 FSGSBASE Message-ID: <202005260912.8867B3AA@keescook> References: <20200526052848.605423-1-andi@firstfloor.org> <20200526065618.GC2580410@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200526065618.GC2580410@kroah.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, May 26, 2020 at 08:56:18AM +0200, Greg KH wrote: > What about those systems that panic-on-warn? This is (modulo the general discussion about whether it's the right way to check) the correct use for WARN*(). It's an undesirable system state; people choosing panic-on-warn want this: https://www.kernel.org/doc/html/latest/process/deprecated.html#bug-and-bug-on -- Kees Cook