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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 A1064C433DF for ; Fri, 15 May 2020 17:28:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7C1152073E for ; Fri, 15 May 2020 17:28:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1589563697; bh=p66GI+uTo7YFHULVF+gV8GMNJV+n4qtI5rkkXvHNSgA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Bizfj2QDkovnIG0RHRAIR9wx9PF+qhzloa7YCdlL1cKbqMksgMtPYzz5hrXw7xXkx VI87EALWMPMza8nOP13+zf2o/Dxe5o1mXFD/5qPmLW267BDwvf0EpYA6K2nLl9He7m X6LPfPFWMxz0Rbg6SkLv/Zj4nDAbkagiQglbprRA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726707AbgEOR2Q (ORCPT ); Fri, 15 May 2020 13:28:16 -0400 Received: from mail.kernel.org ([198.145.29.99]:53210 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726663AbgEOR2N (ORCPT ); Fri, 15 May 2020 13:28:13 -0400 Received: from localhost.localdomain (236.31.169.217.in-addr.arpa [217.169.31.236]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 664B420756; Fri, 15 May 2020 17:28:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1589563693; bh=p66GI+uTo7YFHULVF+gV8GMNJV+n4qtI5rkkXvHNSgA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=MzT4gx/SEvgCF35wdoC8o12qutuMXLDyvFTvlIapI95GJch+y536OIiJeafpy7ktV PRPft1PnSAwuL2gnIi72NGdVmAEKyRUHbLwyjtFw1nqHf+WMWjtRXfcEwPQMuppVGS OgLKeU41E1vqgbhfujljiGor4MjYsDSlaKhIKjFk= From: Will Deacon To: linux-kernel@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org, Will Deacon , Sami Tolvanen , Kees Cook , Catalin Marinas , Mark Rutland , Jann Horn , Ard Biesheuvel , Peter Zijlstra , kernel-team@android.com Subject: [PATCH 3/6] arm64: scs: Use 'scs_sp' register alias for x18 Date: Fri, 15 May 2020 18:27:53 +0100 Message-Id: <20200515172756.27185-4-will@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200515172756.27185-1-will@kernel.org> References: <20200515172756.27185-1-will@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org x18 holds the SCS stack pointer value, so introduce a register alias to make this easier to read in assembly code. Signed-off-by: Will Deacon --- arch/arm64/include/asm/scs.h | 6 ++++-- arch/arm64/kernel/entry.S | 10 +++++----- arch/arm64/kernel/head.S | 2 +- 3 files changed, 10 insertions(+), 8 deletions(-) diff --git a/arch/arm64/include/asm/scs.h b/arch/arm64/include/asm/scs.h index 6b8cf4352fe3..d46efdd2060a 100644 --- a/arch/arm64/include/asm/scs.h +++ b/arch/arm64/include/asm/scs.h @@ -7,12 +7,14 @@ #include #ifdef CONFIG_SHADOW_CALL_STACK + scs_sp .req x18 + .macro scs_load tsk, tmp - ldr x18, [\tsk, #TSK_TI_SCS_SP] + ldr scs_sp, [\tsk, #TSK_TI_SCS_SP] .endm .macro scs_save tsk, tmp - str x18, [\tsk, #TSK_TI_SCS_SP] + str scs_sp, [\tsk, #TSK_TI_SCS_SP] .endm #else .macro scs_load tsk, tmp diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S index cb0516e6f963..741faf0706f1 100644 --- a/arch/arm64/kernel/entry.S +++ b/arch/arm64/kernel/entry.S @@ -394,7 +394,7 @@ alternative_insn eret, nop, ARM64_UNMAP_KERNEL_AT_EL0 .macro irq_stack_entry mov x19, sp // preserve the original sp #ifdef CONFIG_SHADOW_CALL_STACK - mov x24, x18 // preserve the original shadow stack + mov x24, scs_sp // preserve the original shadow stack #endif /* @@ -416,7 +416,7 @@ alternative_insn eret, nop, ARM64_UNMAP_KERNEL_AT_EL0 #ifdef CONFIG_SHADOW_CALL_STACK /* also switch to the irq shadow stack */ - adr_this_cpu x18, irq_shadow_call_stack, x26 + adr_this_cpu scs_sp, irq_shadow_call_stack, x26 #endif 9998: @@ -430,7 +430,7 @@ alternative_insn eret, nop, ARM64_UNMAP_KERNEL_AT_EL0 .macro irq_stack_exit mov sp, x19 #ifdef CONFIG_SHADOW_CALL_STACK - mov x18, x24 + mov scs_sp, x24 #endif .endm @@ -1071,9 +1071,9 @@ SYM_CODE_START(__sdei_asm_handler) #ifdef CONFIG_SHADOW_CALL_STACK /* Use a separate shadow call stack for normal and critical events */ cbnz w4, 3f - adr_this_cpu dst=x18, sym=sdei_shadow_call_stack_normal, tmp=x6 + adr_this_cpu dst=scs_sp, sym=sdei_shadow_call_stack_normal, tmp=x6 b 4f -3: adr_this_cpu dst=x18, sym=sdei_shadow_call_stack_critical, tmp=x6 +3: adr_this_cpu dst=scs_sp, sym=sdei_shadow_call_stack_critical, tmp=x6 4: #endif diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S index 2b01c19c5483..1293baddfd20 100644 --- a/arch/arm64/kernel/head.S +++ b/arch/arm64/kernel/head.S @@ -426,7 +426,7 @@ SYM_FUNC_START_LOCAL(__primary_switched) mov x29, sp #ifdef CONFIG_SHADOW_CALL_STACK - adr_l x18, init_shadow_call_stack // Set shadow call stack + adr_l scs_sp, init_shadow_call_stack // Set shadow call stack #endif str_l x21, __fdt_pointer, x5 // Save FDT pointer -- 2.26.2.761.g0e0b3e54be-goog