From patchwork Mon Jan 24 18:35:22 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 535383 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 66D99C433EF for ; Mon, 24 Jan 2022 21:43:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1456574AbiAXVjd (ORCPT ); Mon, 24 Jan 2022 16:39:33 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53810 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1453928AbiAXVbS (ORCPT ); Mon, 24 Jan 2022 16:31:18 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 72672C06137B; Mon, 24 Jan 2022 12:20:07 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 305BAB8122F; Mon, 24 Jan 2022 20:20:06 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3DE94C340E5; Mon, 24 Jan 2022 20:20:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1643055604; bh=Fy97BY3BCmq+EiEuDqWIRCj+/y9yRMgy604pK4Qo1iA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=undDHj5LqMSYSla+RNLhQjYKm42mbMsR8kZVfhmQxM3ZXza/MIdAJJUsmOca9Tso/ qQaQ/oxvtETze/e1xpOZNALDgFJuZAebT3OVFRwpsA3R8EqGKr1vGaPeYrb1kYMtKN k9sMTcJ8G+kPuuZn97s7ZqlSR58R0xMb8HCjUBXo= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Reiji Watanabe , Catalin Marinas , Sasha Levin Subject: [PATCH 5.15 205/846] arm64: mte: DC {GVA, GZVA} shouldnt be used when DCZID_EL0.DZP == 1 Date: Mon, 24 Jan 2022 19:35:22 +0100 Message-Id: <20220124184108.001144253@linuxfoundation.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220124184100.867127425@linuxfoundation.org> References: <20220124184100.867127425@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Reiji Watanabe [ Upstream commit 685e2564daa1493053fcd7f1dbed38b35ee2f3cb ] Currently, mte_set_mem_tag_range() and mte_zero_clear_page_tags() use DC {GVA,GZVA} unconditionally. But, they should make sure that DCZID_EL0.DZP, which indicates whether or not use of those instructions is prohibited, is zero when using those instructions. Use ST{G,ZG,Z2G} instead when DCZID_EL0.DZP == 1. Fixes: 013bb59dbb7c ("arm64: mte: handle tags zeroing at page allocation time") Fixes: 3d0cca0b02ac ("kasan: speed up mte_set_mem_tag_range") Signed-off-by: Reiji Watanabe Link: https://lore.kernel.org/r/20211206004736.1520989-3-reijiw@google.com Signed-off-by: Catalin Marinas Signed-off-by: Sasha Levin --- arch/arm64/include/asm/mte-kasan.h | 8 +++++--- arch/arm64/lib/mte.S | 8 +++++++- 2 files changed, 12 insertions(+), 4 deletions(-) diff --git a/arch/arm64/include/asm/mte-kasan.h b/arch/arm64/include/asm/mte-kasan.h index 22420e1f8c037..26e013e540ae2 100644 --- a/arch/arm64/include/asm/mte-kasan.h +++ b/arch/arm64/include/asm/mte-kasan.h @@ -84,10 +84,12 @@ static inline void __dc_gzva(u64 p) static inline void mte_set_mem_tag_range(void *addr, size_t size, u8 tag, bool init) { - u64 curr, mask, dczid_bs, end1, end2, end3; + u64 curr, mask, dczid, dczid_bs, dczid_dzp, end1, end2, end3; /* Read DC G(Z)VA block size from the system register. */ - dczid_bs = 4ul << (read_cpuid(DCZID_EL0) & 0xf); + dczid = read_cpuid(DCZID_EL0); + dczid_bs = 4ul << (dczid & 0xf); + dczid_dzp = (dczid >> 4) & 1; curr = (u64)__tag_set(addr, tag); mask = dczid_bs - 1; @@ -106,7 +108,7 @@ static inline void mte_set_mem_tag_range(void *addr, size_t size, u8 tag, */ #define SET_MEMTAG_RANGE(stg_post, dc_gva) \ do { \ - if (size >= 2 * dczid_bs) { \ + if (!dczid_dzp && size >= 2 * dczid_bs) {\ do { \ curr = stg_post(curr); \ } while (curr < end1); \ diff --git a/arch/arm64/lib/mte.S b/arch/arm64/lib/mte.S index e83643b3995f4..f531dcb95174a 100644 --- a/arch/arm64/lib/mte.S +++ b/arch/arm64/lib/mte.S @@ -43,17 +43,23 @@ SYM_FUNC_END(mte_clear_page_tags) * x0 - address to the beginning of the page */ SYM_FUNC_START(mte_zero_clear_page_tags) + and x0, x0, #(1 << MTE_TAG_SHIFT) - 1 // clear the tag mrs x1, dczid_el0 + tbnz x1, #4, 2f // Branch if DC GZVA is prohibited and w1, w1, #0xf mov x2, #4 lsl x1, x2, x1 - and x0, x0, #(1 << MTE_TAG_SHIFT) - 1 // clear the tag 1: dc gzva, x0 add x0, x0, x1 tst x0, #(PAGE_SIZE - 1) b.ne 1b ret + +2: stz2g x0, [x0], #(MTE_GRANULE_SIZE * 2) + tst x0, #(PAGE_SIZE - 1) + b.ne 2b + ret SYM_FUNC_END(mte_zero_clear_page_tags) /*