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 X-Spam-Level: X-Spam-Status: No, score=-10.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 30E7DC433E0 for ; Tue, 16 Jun 2020 10:52:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 12DAA20739 for ; Tue, 16 Jun 2020 10:52:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728414AbgFPKwF (ORCPT ); Tue, 16 Jun 2020 06:52:05 -0400 Received: from verein.lst.de ([213.95.11.211]:37565 "EHLO verein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726692AbgFPKwD (ORCPT ); Tue, 16 Jun 2020 06:52:03 -0400 Received: by verein.lst.de (Postfix, from userid 2407) id 4875968AEF; Tue, 16 Jun 2020 12:52:00 +0200 (CEST) Date: Tue, 16 Jun 2020 12:52:00 +0200 From: Christoph Hellwig To: Peter Zijlstra Cc: Christoph Hellwig , Dexuan Cui , vkuznets , Stephen Hemminger , Andy Lutomirski , Andy Lutomirski , Michael Kelley , Ju-Hyoung Lee , "x86@kernel.org" , "linux-hyperv@vger.kernel.org" , "linux-kernel@vger.kernel.org" , KY Srinivasan , Tom Lendacky Subject: Re: hv_hypercall_pg page permissios Message-ID: <20200616105200.GA32175@lst.de> References: <20200616072318.GA17600@lst.de> <20200616101807.GO2531@hirez.programming.kicks-ass.net> <20200616102350.GA29684@lst.de> <20200616102412.GB29684@lst.de> <20200616103137.GQ2531@hirez.programming.kicks-ass.net> <20200616103313.GA30833@lst.de> <20200616104032.GR2531@hirez.programming.kicks-ass.net> <20200616104230.GA31314@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200616104230.GA31314@lst.de> User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jun 16, 2020 at 12:42:30PM +0200, Christoph Hellwig wrote: > On Tue, Jun 16, 2020 at 12:40:32PM +0200, Peter Zijlstra wrote: > > On Tue, Jun 16, 2020 at 12:33:13PM +0200, Christoph Hellwig wrote: > > > sorry, s/ftrace/kprobes/. See my updated branch here: > > > > > > http://git.infradead.org/users/hch/misc.git/shortlog/refs/heads/module_alloc-cleanup > > > > Ah the insn slot page, yes. Didn't you just loose VM_FLUSH_RESET_PERMS > > there? > > Yes, we did. vmalloc_exec had it, but given that module_alloc didn't > allocate executable on x86 it didn't. I guess we should make sure it > is set by the low-level vmalloc code if exec permissions are set to > sort this mess out. I think something like this should solve the issue: -- diff --git a/arch/x86/include/asm/module.h b/arch/x86/include/asm/module.h index e988bac0a4a1c3..716e4de44a8e78 100644 --- a/arch/x86/include/asm/module.h +++ b/arch/x86/include/asm/module.h @@ -13,4 +13,6 @@ struct mod_arch_specific { #endif }; +void *module_alloc_prot(unsigned long size, pgprot_t prot); + #endif /* _ASM_X86_MODULE_H */ diff --git a/arch/x86/kernel/module.c b/arch/x86/kernel/module.c index 34b153cbd4acb4..4db6e655120960 100644 --- a/arch/x86/kernel/module.c +++ b/arch/x86/kernel/module.c @@ -65,8 +65,10 @@ static unsigned long int get_module_load_offset(void) } #endif -void *module_alloc(unsigned long size) +void *module_alloc_prot(unsigned long size, pgprot_t prot) { + unsigned int flags = (pgprot_val(prot) & _PAGE_NX) ? + 0 : VM_FLUSH_RESET_PERMS; void *p; if (PAGE_ALIGN(size) > MODULES_LEN) @@ -75,7 +77,7 @@ void *module_alloc(unsigned long size) p = __vmalloc_node_range(size, MODULE_ALIGN, MODULES_VADDR + get_module_load_offset(), MODULES_END, GFP_KERNEL, - PAGE_KERNEL, 0, NUMA_NO_NODE, + prot, flags, NUMA_NO_NODE, __builtin_return_address(0)); if (p && (kasan_module_alloc(p, size) < 0)) { vfree(p); @@ -85,6 +87,11 @@ void *module_alloc(unsigned long size) return p; } +void *module_alloc(unsigned long size) +{ + return module_alloc_prot(size, PAGE_KERNEL); +} + #ifdef CONFIG_X86_32 int apply_relocate(Elf32_Shdr *sechdrs, const char *strtab,