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=-5.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=ham 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 B651CC31E40 for ; Mon, 12 Aug 2019 15:10:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 85946208C2 for ; Mon, 12 Aug 2019 15:10:57 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="jYgWhBde" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727382AbfHLPK4 (ORCPT ); Mon, 12 Aug 2019 11:10:56 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:45302 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727159AbfHLPK4 (ORCPT ); Mon, 12 Aug 2019 11:10:56 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.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:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=c3bQwvEBKBc0pEEHbp7FCzV/9a7dwVZ1tfrux53aQUk=; b=jYgWhBdeygmMrmgiIfP4I/TdO Ng/+m9UFICPIWdpQpn87luEmnGnHsT0D4NhynrQsF1RI2UO9sd2y58mGBuAP8lole6dISaAFGFo0Y 7OlXkXD/H/PM0dVsmodbKu5KJVjP7AQMVEeluLGto2VNcV8tM8kZop3KJu8e555pDxu5ip0EMyE16 gGxzR379ivWAHtliDLkHevf+cc6Ezq88GcRxRCj6unpsXVaBkQYcDZiofRfCq371ReeJTzO/T12Ih o55L1GOfElemhDjtVad7hpNu/yr8fLLGpdEwrOKFFDsqstJUVMPlU2waSEdLINCeBu91lyUBCS+rO /J4ePhi7w==; Received: from hch by bombadil.infradead.org with local (Exim 4.92 #3 (Red Hat Linux)) id 1hxByE-0001gG-Rz; Mon, 12 Aug 2019 15:10:50 +0000 Date: Mon, 12 Aug 2019 08:10:50 -0700 From: Christoph Hellwig To: Nick Hu Cc: alankao@andestech.com, paul.walmsley@sifive.com, palmer@sifive.com, aou@eecs.berkeley.edu, green.hu@gmail.com, deanbo422@gmail.com, tglx@linutronix.de, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, aryabinin@virtuozzo.com, glider@google.com, dvyukov@google.com, Anup.Patel@wdc.com, gregkh@linuxfoundation.org, alexios.zavras@intel.com, atish.patra@wdc.com, zong@andestech.com, kasan-dev@googlegroups.com Subject: Re: [PATCH 2/2] riscv: Add KASAN support Message-ID: <20190812151050.GJ26897@infradead.org> References: <88358ef8f7cfcb7fd01b6b989eccaddbe00a1e57.1565161957.git.nickhu@andestech.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <88358ef8f7cfcb7fd01b6b989eccaddbe00a1e57.1565161957.git.nickhu@andestech.com> User-Agent: Mutt/1.11.4 (2019-03-13) X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > 2. KASAN can't debug the modules since the modules are allocated in VMALLOC > area. We mapped the shadow memory, which corresponding to VMALLOC area, > to the kasan_early_shadow_page because we don't have enough physical space > for all the shadow memory corresponding to VMALLOC area. How do other architectures solve this problem? > @@ -54,6 +54,8 @@ config RISCV > select EDAC_SUPPORT > select ARCH_HAS_GIGANTIC_PAGE > select ARCH_WANT_HUGE_PMD_SHARE if 64BIT > + select GENERIC_STRNCPY_FROM_USER if KASAN Is there any reason why we can't always enabled this? Also just enabling the generic efficient strncpy_from_user should probably be a separate patch. > + select HAVE_ARCH_KASAN if MMU Based on your cover letter this should be if MMU && 64BIT > #define __HAVE_ARCH_MEMCPY > extern asmlinkage void *memcpy(void *, const void *, size_t); > +extern asmlinkage void *__memcpy(void *, const void *, size_t); > > #define __HAVE_ARCH_MEMMOVE > extern asmlinkage void *memmove(void *, const void *, size_t); > +extern asmlinkage void *__memmove(void *, const void *, size_t); > + > +#define memcpy(dst, src, len) __memcpy(dst, src, len) > +#define memmove(dst, src, len) __memmove(dst, src, len) > +#define memset(s, c, n) __memset(s, c, n) This looks weird and at least needs a very good comment. Also with this we effectively don't need the non-prefixed prototypes anymore. Also you probably want to split the renaming of the mem* routines into a separate patch with a proper changelog. > #include > #include > > +#ifdef CONFIG_KASAN > +#include > +#endif Any good reason to not just always include the header? > + > #ifdef CONFIG_DUMMY_CONSOLE > struct screen_info screen_info = { > .orig_video_lines = 30, > @@ -64,12 +68,17 @@ void __init setup_arch(char **cmdline_p) > > setup_bootmem(); > paging_init(); > + > unflatten_device_tree(); spurious whitespace change. > diff --git a/arch/riscv/kernel/vmlinux.lds.S b/arch/riscv/kernel/vmlinux.lds.S > index 23cd1a9..9700980 100644 > --- a/arch/riscv/kernel/vmlinux.lds.S > +++ b/arch/riscv/kernel/vmlinux.lds.S > @@ -46,6 +46,7 @@ SECTIONS > KPROBES_TEXT > ENTRY_TEXT > IRQENTRY_TEXT > + SOFTIRQENTRY_TEXT Hmm. What is the relation to kasan here? Maybe we should add this separately with a good changelog? > +++ b/arch/riscv/mm/kasan_init.c > @@ -0,0 +1,102 @@ > +// SPDX-License-Identifier: GPL-2.0 This probably also wants a copyright statement. > + // init for swapper_pg_dir Please use /* */ style comments.