From patchwork Thu Oct 31 16:46:22 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 11221633 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 9D4771390 for ; Thu, 31 Oct 2019 16:59:07 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id EF1D02087F for ; Thu, 31 Oct 2019 16:59:06 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="Ru92iBuu" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org EF1D02087F Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-17187-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 26316 invoked by uid 550); 31 Oct 2019 16:58:57 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Delivered-To: mailing list kernel-hardening@lists.openwall.com Delivered-To: moderator for kernel-hardening@lists.openwall.com Received: (qmail 13461 invoked from network); 31 Oct 2019 16:47:00 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=NvkEBCuGDFGmxutij1zSuSKxlsUUBaj5IQr0NLQJ5So=; b=Ru92iBuuYlPhHAFVLWeOs87kE0FiX1qHnTaOtpzTb/jKviPaXonwKKd+N66yjkRYuK cgnBq46YclvPXSguuBJeqzLri7jCCWWG2Dfk0n6Id4jZM2n7hZ/78QAEvq8GFPDPGfUD qNtrv8foscV0AHwaybS2313mz3Cil7NrOo8pDuPY6Jd1tSs6WarJ755+eSf/RomcChV4 7A1jpdn6Ivzs9aO1uXSVTF6S5nlm17BU8Kojsg1aHJT+c27sDLV3569+F5xcQdMXNe/B BAiGEf7hztz5GyYBj6nLqE1P0Jc3Ye8dMxEAQ36afKH6zRhZp6NxcrpWbI9k75gVvReY hMpQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=NvkEBCuGDFGmxutij1zSuSKxlsUUBaj5IQr0NLQJ5So=; b=LvtQusmDBvdrUiN/dGZ200jZAE67YOUeB1MyXlehqKL353j76NtoJ8sraYJrC8gbXd cD4TDDJP1lO+3d/GCVu3xhDOPJ7U26Q0KC4+qM31S3hOKLNQMSgCQTn2kIHvSdT8oiMH piX91iNNGflQeRyrtyA0D+hoDPNLofwI3s/qnT0GfkU71X8vS+MuQ4S4Z5IQae8LxkuF q4sN3LEwjVSztbNJ+2+hah/MmvM8rbEza+dL6z777UyAuetZqDGwp0kRD9e75Y0k5JxP edvbzBNz+aihdqzPYsjukKk4RiLBto0oVPtbrqSM7ajr1dnx1kHDzKTyX4vN/kzEQKKC e16w== X-Gm-Message-State: APjAAAUNBwOG5+wHPYhDzEKj/V6aJFgBMbdp4f5sjE03wjN1hl4OXhji Xxw0r/L40PZMpC9hQ9xUT3Yvz2lsBvKbSkbycQY= X-Google-Smtp-Source: APXvYqyQVapc0HQb2zNlrO9ACUIg0p0PZIO3eKHtqDUB9iKBoqT2ZxFgyWPN3wIre99JvuCaIlvEX84YwMN3a1ZjF+Y= X-Received: by 2002:a63:d809:: with SMTP id b9mr7733622pgh.143.1572540408812; Thu, 31 Oct 2019 09:46:48 -0700 (PDT) Date: Thu, 31 Oct 2019 09:46:22 -0700 In-Reply-To: <20191031164637.48901-1-samitolvanen@google.com> Message-Id: <20191031164637.48901-3-samitolvanen@google.com> Mime-Version: 1.0 References: <20191018161033.261971-1-samitolvanen@google.com> <20191031164637.48901-1-samitolvanen@google.com> X-Mailer: git-send-email 2.24.0.rc0.303.g954a862665-goog Subject: [PATCH v3 02/17] arm64/lib: copy_page: avoid x18 register in assembler code From: samitolvanen@google.com To: Will Deacon , Catalin Marinas , Steven Rostedt , Masami Hiramatsu , Ard Biesheuvel Cc: Dave Martin , Kees Cook , Laura Abbott , Mark Rutland , Nick Desaulniers , Jann Horn , Miguel Ojeda , Masahiro Yamada , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Sami Tolvanen Register x18 will no longer be used as a caller save register in the future, so stop using it in the copy_page() code. Link: https://patchwork.kernel.org/patch/9836869/ Co-developed-by: Ard Biesheuvel [ changed the offset and bias to be explicit ] Signed-off-by: Sami Tolvanen Reviewed-by: Mark Rutland --- arch/arm64/lib/copy_page.S | 38 +++++++++++++++++++------------------- 1 file changed, 19 insertions(+), 19 deletions(-) diff --git a/arch/arm64/lib/copy_page.S b/arch/arm64/lib/copy_page.S index bbb8562396af..290dd3c5266c 100644 --- a/arch/arm64/lib/copy_page.S +++ b/arch/arm64/lib/copy_page.S @@ -34,45 +34,45 @@ alternative_else_nop_endif ldp x14, x15, [x1, #96] ldp x16, x17, [x1, #112] - mov x18, #(PAGE_SIZE - 128) + add x0, x0, #256 add x1, x1, #128 1: - subs x18, x18, #128 + tst x0, #(PAGE_SIZE - 1) alternative_if ARM64_HAS_NO_HW_PREFETCH prfm pldl1strm, [x1, #384] alternative_else_nop_endif - stnp x2, x3, [x0] + stnp x2, x3, [x0, #-256] ldp x2, x3, [x1] - stnp x4, x5, [x0, #16] + stnp x4, x5, [x0, #16 - 256] ldp x4, x5, [x1, #16] - stnp x6, x7, [x0, #32] + stnp x6, x7, [x0, #32 - 256] ldp x6, x7, [x1, #32] - stnp x8, x9, [x0, #48] + stnp x8, x9, [x0, #48 - 256] ldp x8, x9, [x1, #48] - stnp x10, x11, [x0, #64] + stnp x10, x11, [x0, #64 - 256] ldp x10, x11, [x1, #64] - stnp x12, x13, [x0, #80] + stnp x12, x13, [x0, #80 - 256] ldp x12, x13, [x1, #80] - stnp x14, x15, [x0, #96] + stnp x14, x15, [x0, #96 - 256] ldp x14, x15, [x1, #96] - stnp x16, x17, [x0, #112] + stnp x16, x17, [x0, #112 - 256] ldp x16, x17, [x1, #112] add x0, x0, #128 add x1, x1, #128 - b.gt 1b + b.ne 1b - stnp x2, x3, [x0] - stnp x4, x5, [x0, #16] - stnp x6, x7, [x0, #32] - stnp x8, x9, [x0, #48] - stnp x10, x11, [x0, #64] - stnp x12, x13, [x0, #80] - stnp x14, x15, [x0, #96] - stnp x16, x17, [x0, #112] + stnp x2, x3, [x0, #-256] + stnp x4, x5, [x0, #16 - 256] + stnp x6, x7, [x0, #32 - 256] + stnp x8, x9, [x0, #48 - 256] + stnp x10, x11, [x0, #64 - 256] + stnp x12, x13, [x0, #80 - 256] + stnp x14, x15, [x0, #96 - 256] + stnp x16, x17, [x0, #112 - 256] ret ENDPROC(copy_page)