From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f69.google.com (mail-pa0-f69.google.com [209.85.220.69]) by kanga.kvack.org (Postfix) with ESMTP id AAD4E6B0005 for ; Fri, 29 Jul 2016 13:50:53 -0400 (EDT) Received: by mail-pa0-f69.google.com with SMTP id ag5so114469231pad.2 for ; Fri, 29 Jul 2016 10:50:53 -0700 (PDT) Received: from mga11.intel.com (mga11.intel.com. [192.55.52.93]) by mx.google.com with ESMTP id x4si19390801pfa.54.2016.07.29.10.50.52 for ; Fri, 29 Jul 2016 10:50:52 -0700 (PDT) Subject: Re: [PATCH 08/10] x86, pkeys: default to a restrictive init PKRU References: <20160729163009.5EC1D38C@viggo.jf.intel.com> <20160729163021.F3C25D4A@viggo.jf.intel.com> From: Dave Hansen Message-ID: <579B977B.7090609@intel.com> Date: Fri, 29 Jul 2016 10:50:51 -0700 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Andy Lutomirski Cc: "linux-kernel@vger.kernel.org" , X86 ML , Linux API , linux-arch , "linux-mm@kvack.org" , Linus Torvalds , Andrew Morton , Andrew Lutomirski , Mel Gorman , Dave Hansen , Arnd Bergmann On 07/29/2016 10:29 AM, Andy Lutomirski wrote: >> > In the end, this ensures that threads which do not know how to >> > manage their own pkey rights can not do damage to data which is >> > pkey-protected. > I think you missed the fpu__clear() caller in kernel/fpu/signal.c. > > ISTM it might be more comprehensible to change fpu__clear in general > and then special case things you want to behave differently. The code actually already patched the generic fpu__clear(): fpu__clear() -> copy_init_fpstate_to_fpregs() -> copy_init_pkru_to_fpregs() So I think it hit the case you are talking about. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org