From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752186AbdHGSih (ORCPT ); Mon, 7 Aug 2017 14:38:37 -0400 Received: from foss.arm.com ([217.140.101.70]:52686 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752168AbdHGSif (ORCPT ); Mon, 7 Aug 2017 14:38:35 -0400 From: Mark Rutland To: linux-arm-kernel@lists.infradead.org Cc: ard.biesheuvel@linaro.org, catalin.marinas@arm.com, james.morse@arm.com, labbott@redhat.com, linux-kernel@vger.kernel.org, luto@amacapital.net, mark.rutland@arm.com, matt@codeblueprint.co.uk, will.deacon@arm.com, kernel-hardening@lists.openwall.com, keescook@chromium.org Subject: [PATCH 10/14] arm64: assembler: allow adr_this_cpu to use the stack pointer Date: Mon, 7 Aug 2017 19:36:01 +0100 Message-Id: <1502130965-18710-11-git-send-email-mark.rutland@arm.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1502130965-18710-1-git-send-email-mark.rutland@arm.com> References: <1502130965-18710-1-git-send-email-mark.rutland@arm.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Ard Biesheuvel Given that adr_this_cpu already requires a temp register in addition to the destination register, tweak the instruction sequence so that sp may be used as well. This will simplify switching to per-cpu stacks in subsequent patches. While this limits the range of adr_this_cpu, to +/-4GiB, we don't currently use adr_this_cpu in modules, and this is not problematic for the main kernel image. Signed-off-by: Ard Biesheuvel [Mark: add more commit text] Signed-off-by: Mark Rutland Cc: Catalin Marinas Cc: James Morse Cc: Laura Abbott Cc: Will Deacon --- arch/arm64/include/asm/assembler.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h index 610a420..4775af5 100644 --- a/arch/arm64/include/asm/assembler.h +++ b/arch/arm64/include/asm/assembler.h @@ -235,7 +235,8 @@ * @tmp: scratch register */ .macro adr_this_cpu, dst, sym, tmp - adr_l \dst, \sym + adrp \tmp, \sym + add \dst, \tmp, #:lo12:\sym mrs \tmp, tpidr_el1 add \dst, \dst, \tmp .endm -- 1.9.1