From patchwork Sun Sep 11 20:35:22 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Konrad Rzeszutek Wilk X-Patchwork-Id: 9325597 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 5F72F6089F for ; Sun, 11 Sep 2016 20:38:40 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 4E459284EF for ; Sun, 11 Sep 2016 20:38:40 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 4327F28AB5; Sun, 11 Sep 2016 20:38:40 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, UNPARSEABLE_RELAY autolearn=ham version=3.3.1 Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id CDDB528AB1 for ; Sun, 11 Sep 2016 20:38:39 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.84_2) (envelope-from ) id 1bjBTu-00022S-EV; Sun, 11 Sep 2016 20:36:02 +0000 Received: from mail6.bemta6.messagelabs.com ([193.109.254.103]) by lists.xenproject.org with esmtp (Exim 4.84_2) (envelope-from ) id 1bjBTt-00021L-CE for xen-devel@lists.xenproject.org; Sun, 11 Sep 2016 20:36:01 +0000 Received: from [193.109.254.147] by server-8.bemta-6.messagelabs.com id 9E/88-05361-030C5D75; Sun, 11 Sep 2016 20:36:00 +0000 X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFvrFLMWRWlGSWpSXmKPExsUyZ7p8oK7Bgav hBjev8Ft83zKZyYHR4/CHKywBjFGsmXlJ+RUJrBn7Ps1mL9ioWPHvzwfmBsYlIl2MXBxCAh1M El0909kgnG+MEntuPWKCcDYySuz/sw3KmcAosffpbsYuRg4ONgETiTerHEHiIgJtjBLfTmxl7 2Lk5GAWKJN4uPgJK4gtLOAoceL+TCaQehYBVYk7G8NBwrwC7hK/rpxlAwlLCMhLPLtdDxLmBA pvnPOeBSQsJOAmcaLHGCQsIWAs0Terj2UCI98CRoZVjBrFqUVlqUW6hqZ6SUWZ6RkluYmZObq GBmZ6uanFxYnpqTmJScV6yfm5mxiBYcIABDsYvy0LOMQoycGkJMrrv+BquBBfUn5KZUZicUZ8 UWlOavEhRhkODiUJXpP9QDnBotT01Iq0zBxgwMKkJTh4lER4bUHSvMUFibnFmekQqVOMilLiv F/2ASUEQBIZpXlwbbAoucQoKyXMywh0iBBPQWpRbmYJqvwrRnEORiVhXgeQ8TyZeSVw018BLW YCWvx062WQxSWJCCmpBsYc5f5H3ffW9x+dYzSl02nxyy+Wb6tF3nFm6newr5X/0Tp7e+zhRMY dTyZ6rjmeajBb9+nFNWseyQvenlv1jmfr1H9ZLWfXPJzDGV7Rpnw49HZkoWqPicWZOR9r+x6t Ws6093+4Ws2PT9uiYthaXy3Z8jDlk7e5XPQTzTtTBYNWZkaUvnyuuCFHiaU4I9FQi7moOBEAv YXMw40CAAA= X-Env-Sender: konrad.wilk@oracle.com X-Msg-Ref: server-14.tower-27.messagelabs.com!1473626158!46256805!1 X-Originating-IP: [156.151.31.81] X-SpamReason: No, hits=0.0 required=7.0 tests=sa_preprocessor: VHJ1c3RlZCBJUDogMTU2LjE1MS4zMS44MSA9PiAyODgzMzk=\n X-StarScan-Received: X-StarScan-Version: 8.84; banners=-,-,- X-VirusChecked: Checked Received: (qmail 31723 invoked from network); 11 Sep 2016 20:35:59 -0000 Received: from userp1040.oracle.com (HELO userp1040.oracle.com) (156.151.31.81) by server-14.tower-27.messagelabs.com with DHE-RSA-AES256-GCM-SHA384 encrypted SMTP; 11 Sep 2016 20:35:59 -0000 Received: from aserv0021.oracle.com (aserv0021.oracle.com [141.146.126.233]) by userp1040.oracle.com (Sentrion-MTA-4.3.2/Sentrion-MTA-4.3.2) with ESMTP id u8BKZoS4021204 (version=TLSv1 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Sun, 11 Sep 2016 20:35:50 GMT Received: from aserv0122.oracle.com (aserv0122.oracle.com [141.146.126.236]) by aserv0021.oracle.com (8.13.8/8.13.8) with ESMTP id u8BKZoF6013334 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Sun, 11 Sep 2016 20:35:50 GMT Received: from abhmp0016.oracle.com (abhmp0016.oracle.com [141.146.116.22]) by aserv0122.oracle.com (8.14.4/8.14.4) with ESMTP id u8BKZnE7025597; Sun, 11 Sep 2016 20:35:49 GMT Received: from localhost.localdomain.com (/209.6.196.81) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Sun, 11 Sep 2016 13:35:49 -0700 From: Konrad Rzeszutek Wilk To: xen-devel@lists.xenproject.org, konrad@kernel.org, julien.grall@arm.com, sstabellini@kernel.org, ross.lagerwall@citrix.com Date: Sun, 11 Sep 2016 16:35:22 -0400 Message-Id: <1473626125-13683-16-git-send-email-konrad.wilk@oracle.com> X-Mailer: git-send-email 2.4.11 In-Reply-To: <1473626125-13683-1-git-send-email-konrad.wilk@oracle.com> References: <1473626125-13683-1-git-send-email-konrad.wilk@oracle.com> X-Source-IP: aserv0021.oracle.com [141.146.126.233] Cc: andrew.cooper3@citrix.com, Jan Beulich , Konrad Rzeszutek Wilk Subject: [Xen-devel] [PATCH v3 15/18] bug/x86/arm: Align bug_frames sections. X-BeenThere: xen-devel@lists.xen.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: xen-devel-bounces@lists.xen.org Sender: "Xen-devel" X-Virus-Scanned: ClamAV using ClamSMTP Most of the WARN_ON or BUG_ON sections are properly aligned on x86. However on ARM and on x86 assembler the macros don't include any aligment information - hence they end up being the default byte granularity. On ARM32 it is paramount that the aligment is word-size (4) otherwise if one tries to use (uint32_t*) access (such as livepatch ELF relocations) we get a Data Abort. Enforcing bug_frames to have the proper aligment across all architectures and in both C and x86 makes them all the same. Furthermore on x86 the bloat-o-meter detects that with this change: [konrad@char xen]$ ~/linux/scripts/bloat-o-meter xen-syms xen-syms.align4 add/remove: 0/0 grow/shrink: 3/14 up/down: 115/-1497 (-1382) function old new delta mod_l1_entry 1490 1587 +97 p2m_switch_domain_altp2m_by_id 520 533 +13 p2m_switch_vcpu_altp2m_by_id 453 458 +5 machine_kexec 263 261 -2 hvm_do_IRQ_dpci 244 242 -2 sh_page_fault__guest_4 8252 8192 -60 sh_audit_gw 1529 1462 -67 validate_gl3e 337 264 -73 validate_gl4e 449 375 -74 p2m_altp2m_lazy_copy 730 652 -78 set_typed_p2m_entry 1346 1259 -87 virt_to_xen_l2e 491 365 -126 sh_x86_emulate_write__guest_4 443 288 -155 p2m_mem_access_check 1733 1576 -157 sh_x86_emulate_cmpxchg__guest_4 512 349 -163 __get_gfn_type_access 709 542 -167 map_pages_to_xen 4430 4144 -286 Total: Before=1974033, After=1972651, chg -0.07% We end up making the binary file a bit smaller. On ARM32: add/remove: 1/0 grow/shrink: 0/1 up/down: 384/-288 (96) function old new delta gnttab_unpopulate_status_frames - 384 +384 do_grant_table_op 10808 10520 -288 And ARM64: add/remove: 1/2 grow/shrink: 0/1 up/down: 4164/-4236 (-72) function old new delta gnttab_map_grant_ref - 4164 +4164 do_grant_table_op 9892 9836 -56 grant_map_exists 300 - -300 __gnttab_map_grant_ref 3880 - -3880 Signed-off-by: Konrad Rzeszutek Wilk --- Cc: Julien Grall Cc: Stefano Stabellini Cc: Jan Beulich Cc: Andrew Cooper v3: First submission. Replaces the "livepatch/elf: Adjust section aligment to word" patch. --- xen/include/asm-arm/bug.h | 1 + xen/include/asm-x86/bug.h | 1 + 2 files changed, 2 insertions(+) diff --git a/xen/include/asm-arm/bug.h b/xen/include/asm-arm/bug.h index 68353e1..773d63e 100644 --- a/xen/include/asm-arm/bug.h +++ b/xen/include/asm-arm/bug.h @@ -52,6 +52,7 @@ struct bug_frame { ".popsection\n" \ ".pushsection .bug_frames." __stringify(type) ", \"a\", %progbits\n"\ "4:\n" \ + ".align 4\n" \ ".long (1b - 4b)\n" \ ".long (2b - 4b)\n" \ ".long (3b - 4b)\n" \ diff --git a/xen/include/asm-x86/bug.h b/xen/include/asm-x86/bug.h index c5d2d4c..9bb4a19 100644 --- a/xen/include/asm-x86/bug.h +++ b/xen/include/asm-x86/bug.h @@ -98,6 +98,7 @@ extern const struct bug_frame __start_bug_frames[], .popsection .pushsection .bug_frames.\type, "a", @progbits + .p2align 2 .L\@bf: .long (.L\@ud - .L\@bf) + \ ((\line >> BUG_LINE_LO_WIDTH) << BUG_DISP_WIDTH)