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=-15.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 44277C433DB for ; Tue, 2 Feb 2021 15:44:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0D9A164F4B for ; Tue, 2 Feb 2021 15:44:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232427AbhBBPnv (ORCPT ); Tue, 2 Feb 2021 10:43:51 -0500 Received: from mail.kernel.org ([198.145.29.99]:46134 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235752AbhBBPmr (ORCPT ); Tue, 2 Feb 2021 10:42:47 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id F04BF64F4B; Tue, 2 Feb 2021 15:42:03 +0000 (UTC) Date: Tue, 2 Feb 2021 15:42:01 +0000 From: Catalin Marinas To: Andrey Konovalov Cc: Vincenzo Frascino , Dmitry Vyukov , Alexander Potapenko , Marco Elver , Andrew Morton , Will Deacon , Andrey Ryabinin , Peter Collingbourne , Evgenii Stepanov , Branislav Rankov , Kevin Brodsky , kasan-dev@googlegroups.com, linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 10/12] arm64: kasan: simplify and inline MTE functions Message-ID: <20210202154200.GC26895@gaia> References: <17d6bef698d193f5fe0d8baee0e232a351e23a32.1612208222.git.andreyknvl@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <17d6bef698d193f5fe0d8baee0e232a351e23a32.1612208222.git.andreyknvl@google.com> User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Feb 01, 2021 at 08:43:34PM +0100, Andrey Konovalov wrote: > +/* > + * Assign allocation tags for a region of memory based on the pointer tag. > + * Note: The address must be non-NULL and MTE_GRANULE_SIZE aligned and > + * size must be non-zero and MTE_GRANULE_SIZE aligned. > + */ OK, so we rely on the caller to sanity-check the range. Fine by me but I can see (un)poison_range() only doing this for the size. Do we guarantee that the start address is aligned? > +static __always_inline void mte_set_mem_tag_range(void *addr, size_t size, u8 tag) > +{ > + u64 curr, end; > + > + if (!size) > + return; > + > + curr = (u64)__tag_set(addr, tag); > + end = curr + size; > + > + do { > + /* > + * 'asm volatile' is required to prevent the compiler to move > + * the statement outside of the loop. > + */ > + asm volatile(__MTE_PREAMBLE "stg %0, [%0]" > + : > + : "r" (curr) > + : "memory"); > + > + curr += MTE_GRANULE_SIZE; > + } while (curr != end); > +} > > void mte_enable_kernel_sync(void); > void mte_enable_kernel_async(void); > @@ -47,10 +95,12 @@ static inline u8 mte_get_mem_tag(void *addr) > { > return 0xFF; > } > + > static inline u8 mte_get_random_tag(void) > { > return 0xFF; > } > + > static inline void *mte_set_mem_tag_range(void *addr, size_t size, u8 tag) This function used to return a pointer and that's what the dummy static inline does here. However, the new mte_set_mem_tag_range() doesn't return anything. We should have consistency between the two (the new static void definition is fine by me). Otherwise the patch looks fine. Reviewed-by: Catalin Marinas