From patchwork Fri Dec 6 22:13:38 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 11277059 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 1E5501593 for ; Fri, 6 Dec 2019 22:14:26 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 7AE2F206DB for ; Fri, 6 Dec 2019 22:14:25 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="CPqQmv4W" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7AE2F206DB 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-17474-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 17802 invoked by uid 550); 6 Dec 2019 22:14:13 -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 Received: (qmail 17720 invoked from network); 6 Dec 2019 22:14:12 -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=8cEo3bnB2JOErtud3GvPd9W0QqVJKhLYL3PxcgBL0pc=; b=CPqQmv4WqCQBFArArM8RhJECBGvYc1DYgdPm0u6MVe0Oqz9fNy0AzMgv/8cEGG/BAU aAtkoPugaKUj5l+B6gmWuX+5yxOs+N3ZWs/7Q39Wy7REQEzECblVDxd+is2N3naPmb+Z AqE5JEDUA8ZArMaJifiVfToRBNBcxgJbfiPhEMzN4QT7addM2NEiDmiH+MHpEUOrpMuY 5mCBPj6zphQUPpZkvQxiKNqQZVXSG5ZKCqPY/yDTZAouky3k/+Eg/at4qlCky/F1/OE5 FKwHQSFj6kwEepxRANrOWOQ7iDHcCUd0e0fNHAJuNQWb5uPQ20sY1xVXRPXlBPWsO0w5 mmMA== 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=8cEo3bnB2JOErtud3GvPd9W0QqVJKhLYL3PxcgBL0pc=; b=Vpcd2rCfBAIXxROKUBEC0gep9mto7nzO1tRV6nJjUTrBIGJwGqfJDR9anjY13W5vKy s62iJEyixFuHqV9nqsSUg24YpSMCPyK6HVq5GC/ddVGRXK01gtwqpJil4PIyEMhf+qCR vZUCi3axkFbUF2Jq4p+7qaxi0RqoH2+S2GEkOpWElHGK1dIMD6iIDRbch33gUBpa/h99 3ak2ZX3yqbtCrt0L9y0gLKWeKH7EHlt3WRlC5vrppmX7hCkLoVVIFTbyGBz3arHPFPcq Cn+EPlrE5K50eWO9tRfoEovoqia96Sk96Bcw9w4Zor7/4rN4kEdNQWCx7Gwjmfyd7b7S 5ppg== X-Gm-Message-State: APjAAAUdwzeCJTHb4CuylmjQ+5hZQU7LAJ8KrPF/kd6KKlABy38Xbv3x R9NTESrvMFeEJutOuNwk2oI6RoxgELA6JV+EAOY= X-Google-Smtp-Source: APXvYqyRfdS5aqE39eaRAOxLgcN4AWsr5dwZL7gm38UAYSLZ0IPRBNt46Y6TodltgXxQPThKbmHblBbcL2qiJvc2D0M= X-Received: by 2002:a63:184d:: with SMTP id 13mr6053846pgy.132.1575670440912; Fri, 06 Dec 2019 14:14:00 -0800 (PST) Date: Fri, 6 Dec 2019 14:13:38 -0800 In-Reply-To: <20191206221351.38241-1-samitolvanen@google.com> Message-Id: <20191206221351.38241-3-samitolvanen@google.com> Mime-Version: 1.0 References: <20191018161033.261971-1-samitolvanen@google.com> <20191206221351.38241-1-samitolvanen@google.com> X-Mailer: git-send-email 2.24.0.393.g34dc348eaf-goog Subject: [PATCH v6 02/15] arm64/lib: copy_page: avoid x18 register in assembler code From: Sami Tolvanen To: Will Deacon , Catalin Marinas , Steven Rostedt , Masami Hiramatsu , Ard Biesheuvel , Mark Rutland Cc: Dave Martin , Kees Cook , Laura Abbott , Marc Zyngier , 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 From: Ard Biesheuvel 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/ Signed-off-by: Ard Biesheuvel [Sami: 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)