From mboxrd@z Thu Jan 1 00:00:00 1970 From: catalin.marinas@arm.com (Catalin Marinas) Date: Fri, 24 Oct 2014 11:11:42 +0100 Subject: [PATCH 1/2] arm: hwcap: add new hwcap for identifying PXN bits In-Reply-To: <1414144655-25204-1-git-send-email-js07.lee@gmail.com> References: <1414144655-25204-1-git-send-email-js07.lee@gmail.com> Message-ID: <20141024101142.GA1955@localhost> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Fri, Oct 24, 2014 at 10:57:34AM +0100, Jungseung Lee wrote: > Modern ARMv7-A/R cores can optionally implement below new > hardware feature: > > - PXN: > Privileged execute-never(PXN) is a security feature. PXN bit > determines whether the processor can execute software from > the region. This is effective solution against ret2usr attack. > > This patch adds new HWCAP defines to describe new feature. > On an implementation that does not include the LPAE, PXN is > optionally supported. Why does the user need to know about such feature? Just enable it in the kernel if available. -- Catalin