From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 961FEC4332F for ; Fri, 14 Oct 2022 15:52:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231164AbiJNPww (ORCPT ); Fri, 14 Oct 2022 11:52:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36858 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231185AbiJNPwu (ORCPT ); Fri, 14 Oct 2022 11:52:50 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3FB671C77CC; Fri, 14 Oct 2022 08:52:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=uURYEhJNF/y4ef2ytvd2xFiDhwfWuIdCXYX1RDrMcEU=; b=FI8zrVaVC/8UN/s+IiozYmQHKy Y557SBFHLKXCkrCnS2qkGQO6WBcuTY9UCgzKthC5OYmAmaNRDidzUfdySBCzwEmZak48g63V7W0se harj0CbOOajx4M9COGuuEFZB31SGwzSyEhtOzDzwtY/UdMeFeYkVkbJUgsabjCu3o8WnPFWYW7VJX yhyvlOKxkjg0twaCH2fp4fjBU+DMUPJ3kNPjuOsacZZWAZ+xrgJ9JXv7/akKIdWxrls5DXgfpU87E eQT1cZyX4+yNpZBCtP+moPbnXDOYLTwpdr6p37FiH/BfjURSfu6BObNi1jef0hOl3BRHNT5bYE6+j +NS805UA==; Received: from j130084.upc-j.chello.nl ([24.132.130.84] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1ojMys-007jm1-O0; Fri, 14 Oct 2022 15:52:14 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 7E68A30008D; Fri, 14 Oct 2022 17:52:08 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 67EF92C1B1259; Fri, 14 Oct 2022 17:52:08 +0200 (CEST) Date: Fri, 14 Oct 2022 17:52:08 +0200 From: Peter Zijlstra To: Rick Edgecombe Cc: x86@kernel.org, "H . Peter Anvin" , Thomas Gleixner , Ingo Molnar , linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-api@vger.kernel.org, Arnd Bergmann , Andy Lutomirski , Balbir Singh , Borislav Petkov , Cyrill Gorcunov , Dave Hansen , Eugene Syromiatnikov , Florian Weimer , "H . J . Lu" , Jann Horn , Jonathan Corbet , Kees Cook , Mike Kravetz , Nadav Amit , Oleg Nesterov , Pavel Machek , Randy Dunlap , "Ravi V . Shankar" , Weijiang Yang , "Kirill A . Shutemov" , joao.moreira@intel.com, John Allen , kcc@google.com, eranian@google.com, rppt@kernel.org, jamorris@linux.microsoft.com, dethoma@microsoft.com, Yu-cheng Yu Subject: Re: [PATCH v2 17/39] mm: Fixup places that call pte_mkwrite() directly Message-ID: References: <20220929222936.14584-1-rick.p.edgecombe@intel.com> <20220929222936.14584-18-rick.p.edgecombe@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220929222936.14584-18-rick.p.edgecombe@intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Sep 29, 2022 at 03:29:14PM -0700, Rick Edgecombe wrote: > diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c > index 7327b2573f7c..b49372c7de41 100644 > --- a/mm/userfaultfd.c > +++ b/mm/userfaultfd.c > @@ -63,6 +63,7 @@ int mfill_atomic_install_pte(struct mm_struct *dst_mm, pmd_t *dst_pmd, > int ret; > pte_t _dst_pte, *dst_pte; > bool writable = dst_vma->vm_flags & VM_WRITE; > + bool shstk = dst_vma->vm_flags & VM_SHADOW_STACK; > bool vm_shared = dst_vma->vm_flags & VM_SHARED; > bool page_in_cache = page->mapping; > spinlock_t *ptl; > @@ -83,9 +84,12 @@ int mfill_atomic_install_pte(struct mm_struct *dst_mm, pmd_t *dst_pmd, > writable = false; > } > > - if (writable) > - _dst_pte = pte_mkwrite(_dst_pte); > - else > + if (writable) { > + if (shstk) > + _dst_pte = pte_mkwrite_shstk(_dst_pte); > + else > + _dst_pte = pte_mkwrite(_dst_pte); > + } else > /* > * We need this to make sure write bit removed; as mk_pte() > * could return a pte with write bit set. Urgh.. that's unfortunate. But yeah, I don't see a way to make that pretty either.