From patchwork Mon Feb 10 14:35:14 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Thomas Huth X-Patchwork-Id: 11373389 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 A4DB914B4 for ; Mon, 10 Feb 2020 14:35:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8608D2082F for ; Mon, 10 Feb 2020 14:35:27 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="ZuKhOp3o" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727775AbgBJOf0 (ORCPT ); Mon, 10 Feb 2020 09:35:26 -0500 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:21388 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726961AbgBJOf0 (ORCPT ); Mon, 10 Feb 2020 09:35:26 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1581345325; 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=wxwzfEhD9lbwARMsqltvsS9V4fe5j1xN/yz0t79bhtk=; b=ZuKhOp3ofanW/GjapSxcDh4UnINJWFu4lSOi8ORlSmZgcxvAoP4KO47NTc3QuPV55ZX28u dSIyt+Doc8MivMt/aITzF/5nrl5yY9CEDAIXT23xYyD2hM8hKclbG51enfuAX1PBSJA+Ml 70RVa7A90oRy17lExIIA1lxAYj59/pg= 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-365-eIlyUFOpOBCarOq_q-uY1w-1; Mon, 10 Feb 2020 09:35:21 -0500 X-MC-Unique: eIlyUFOpOBCarOq_q-uY1w-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id BEC008017CC for ; Mon, 10 Feb 2020 14:35:20 +0000 (UTC) Received: from thuth.com (ovpn-116-219.ams2.redhat.com [10.36.116.219]) by smtp.corp.redhat.com (Postfix) with ESMTP id AFCA760BF1; Mon, 10 Feb 2020 14:35:19 +0000 (UTC) From: Thomas Huth To: kvm@vger.kernel.org, Paolo Bonzini Cc: Vitaly Kuznetsov Subject: [kvm-unit-tests v2 PATCH] Fixes for the umip test Date: Mon, 10 Feb 2020 15:35:14 +0100 Message-Id: <20200210143514.5347-1-thuth@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 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 --- v2: Add parentheses and fix doubled whitespace as requested by Vitaly x86/umip.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/x86/umip.c b/x86/umip.c index 7eee294..339bea4 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 +160,7 @@ 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) - 2]), [fn]"r"(fn), [arg]"D"(arg), [kernel_ds]"i"(KERNEL_DS),