From nobody Tue Oct 28 12:17:37 2025 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 151448478226390.95378804038523; Thu, 28 Dec 2017 10:13:02 -0800 (PST) Received: from localhost ([::1]:60649 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eUcfo-00039y-3Q for importer@patchew.org; Thu, 28 Dec 2017 13:12:56 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:54632) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eUcbR-00084S-N7 for qemu-devel@nongnu.org; Thu, 28 Dec 2017 13:08:27 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eUcbQ-00013f-3w for qemu-devel@nongnu.org; Thu, 28 Dec 2017 13:08:25 -0500 Received: from mav.lukeshu.com ([2001:19f0:5c00:8069:5400:ff:fe26:6a86]:41958) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1eUcbQ-000134-0c for qemu-devel@nongnu.org; Thu, 28 Dec 2017 13:08:24 -0500 Received: from build64-par (unknown [IPv6:2601:803:202:9275:da50:e6ff:fe00:4a5b]) by mav.lukeshu.com (Postfix) with ESMTPSA id 9DF198050A; Thu, 28 Dec 2017 13:08:20 -0500 (EST) From: Luke Shumaker To: qemu-devel@nongnu.org Date: Thu, 28 Dec 2017 13:08:11 -0500 Message-Id: <20171228180814.9749-9-lukeshu@lukeshu.com> X-Mailer: git-send-email 2.15.1 In-Reply-To: <20171228180814.9749-1-lukeshu@lukeshu.com> References: <20171228180814.9749-1-lukeshu@lukeshu.com> X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 2001:19f0:5c00:8069:5400:ff:fe26:6a86 Subject: [Qemu-devel] [PATCH 08/10] linux-user: init_guest_space: Don't try to align if we'll reject it X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Luke Shumaker , Riku Voipio , Laurent Vivier Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RSF_0 Z_629925259 SPT_0 Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" From: Luke Shumaker If the ensure-alignment code gets triggered, then the "if (host_start && real_start !=3D current_start)" check will always trigge= r, so save 2 syscalls and put that check first. Note that we can't just switch to using MAP_FIXED for that check, because then we couldn't differentiate between a failure because "there isn't enough space" and "there isn't enough space *here*". Signed-off-by: Luke Shumaker Reviewed-by: Peter Maydell --- linux-user/elfload.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/linux-user/elfload.c b/linux-user/elfload.c index 5c0ad65611..1b7583d659 100644 --- a/linux-user/elfload.c +++ b/linux-user/elfload.c @@ -1871,6 +1871,11 @@ unsigned long init_guest_space(unsigned long host_st= art, return (unsigned long)-1; } =20 + /* Check to see if the address is valid. */ + if (host_start && real_start !=3D current_start) { + goto try_again; + } + /* Ensure the address is properly aligned. */ if (real_start & ~qemu_host_page_mask) { /* Ideally, we adjust like @@ -1905,11 +1910,6 @@ unsigned long init_guest_space(unsigned long host_st= art, aligned_start =3D real_start; } =20 - /* Check to see if the address is valid. */ - if (host_start && aligned_start !=3D current_start) { - goto try_again; - } - #if defined(TARGET_ARM) && !defined(TARGET_AARCH64) /* On 32-bit ARM, we need to also be able to map the commpage. */ int valid =3D init_guest_commpage(aligned_start - guest_start, --=20 2.15.1