From patchwork Tue May 12 09:44:38 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Thomas Huth X-Patchwork-Id: 11542799 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 EAAD2912 for ; Tue, 12 May 2020 09:44:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D2ED020661 for ; Tue, 12 May 2020 09:44:48 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="LINTnhq6" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728085AbgELJor (ORCPT ); Tue, 12 May 2020 05:44:47 -0400 Received: from us-smtp-1.mimecast.com ([205.139.110.61]:21344 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726187AbgELJor (ORCPT ); Tue, 12 May 2020 05:44:47 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1589276686; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=AlBBtiFsBQAYEIktUSByiopncaRspUIywvSAFY/TY4Q=; b=LINTnhq6nGu8SLJCHTR9ZubOZ8DSrL1XBNYl9+HaK9VW9/wv9ov53dtgkgD9RvnHfvXVi0 m7OJ61NwZYLuywrQ9RdhbheUfohiLWQ6nYPnGXK0RRfNkvGaS35mjzYd6Ty4llxKdMqIxo Fttz7Y/GHKcENIlQYgG4uc1lo69xyGE= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-346-ZJtHkdEHOg2fPbSVxa7bZg-1; Tue, 12 May 2020 05:44:44 -0400 X-MC-Unique: ZJtHkdEHOg2fPbSVxa7bZg-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id DF051835B46 for ; Tue, 12 May 2020 09:44:43 +0000 (UTC) Received: from thuth.com (ovpn-112-112.ams2.redhat.com [10.36.112.112]) by smtp.corp.redhat.com (Postfix) with ESMTP id 0B6625C1B5; Tue, 12 May 2020 09:44:41 +0000 (UTC) From: Thomas Huth To: kvm@vger.kernel.org, Paolo Bonzini Cc: Vitaly Kuznetsov Subject: [kvm-unit-tests v3 PATCH] Fixes for the umip test Date: Tue, 12 May 2020 11:44:38 +0200 Message-Id: <20200512094438.17998-1-thuth@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org When compiling umip.c with -O2 instead of -O1, there are currently two problems. First, the compiler complains: x86/umip.c: In function ‘do_ring3’: x86/umip.c:162:37: error: array subscript 4096 is above array bounds of ‘unsigned char[4096]’ [-Werror=array-bounds] [user_stack_top]"m"(user_stack[sizeof user_stack]), ~~~~~~~~~~^~~~~~~~~~~~~~~~~~~ This can be fixed by initializing the stack to point to one of the last bytes of the array instead. The second problem is that some tests are failing - and this is due to the fact that the GP_ASM macro uses inline asm without the "volatile" keyword - so that the compiler reorders this code in certain cases where it should not. Fix it by adding "volatile" here. Reviewed-by: Vitaly Kuznetsov Signed-off-by: Thomas Huth --- v3: Use "sizeof(long)" instead of "2" x86/umip.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/x86/umip.c b/x86/umip.c index 7eee294..37f1ab8 100644 --- a/x86/umip.c +++ b/x86/umip.c @@ -22,7 +22,8 @@ static void gp_handler(struct ex_regs *regs) #define GP_ASM(stmt, in, clobber) \ - asm ("mov" W " $1f, %[expected_rip]\n\t" \ + asm volatile ( \ + "mov" W " $1f, %[expected_rip]\n\t" \ "movl $2f-1f, %[skip_count]\n\t" \ "1: " stmt "\n\t" \ "2: " \ @@ -159,7 +160,8 @@ static int do_ring3(void (*fn)(const char *), const char *arg) : [ret] "=&a" (ret) : [user_ds] "i" (USER_DS), [user_cs] "i" (USER_CS), - [user_stack_top]"m"(user_stack[sizeof user_stack]), + [user_stack_top]"m"(user_stack[sizeof(user_stack) - + sizeof(long)]), [fn]"r"(fn), [arg]"D"(arg), [kernel_ds]"i"(KERNEL_DS),