From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:5758 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726100AbfJBIWH (ORCPT ); Wed, 2 Oct 2019 04:22:07 -0400 Received: from pps.filterd (m0098413.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x928HFrQ118040 for ; Wed, 2 Oct 2019 04:22:06 -0400 Received: from e06smtp07.uk.ibm.com (e06smtp07.uk.ibm.com [195.75.94.103]) by mx0b-001b2d01.pphosted.com with ESMTP id 2vcnhs4nb6-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Wed, 02 Oct 2019 04:22:05 -0400 Received: from localhost by e06smtp07.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Wed, 2 Oct 2019 09:22:04 +0100 Date: Wed, 2 Oct 2019 10:21:57 +0200 From: Heiko Carstens Subject: Re: [PATCH 5.4-rc1 BUILD FIX] s390: mark __cpacf_query() as __always_inline References: <20191002064605.GA7405@osiris> <20191002070333.GE24815@unicorn.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191002070333.GE24815@unicorn.suse.cz> Message-Id: <20191002082157.GA9535@osiris> Sender: linux-s390-owner@vger.kernel.org List-ID: To: Michal Kubecek Cc: linux-kernel@vger.kernel.org, Jiri Kosina , Vasily Gorbik , Christian Borntraeger , Masahiro Yamada , Linus Torvalds , linux-s390@vger.kernel.org On Wed, Oct 02, 2019 at 09:03:33AM +0200, Michal Kubecek wrote: > On Wed, Oct 02, 2019 at 08:46:05AM +0200, Heiko Carstens wrote: > > On Tue, Oct 01, 2019 at 10:08:01PM +0200, Jiri Kosina wrote: > > > > > > In file included from arch/s390/kvm/kvm-s390.c:44: > > > ./arch/s390/include/asm/cpacf.h: In function '__cpacf_query': > > > ./arch/s390/include/asm/cpacf.h:179:2: warning: asm operand 3 probably doesn't match constraints > > > 179 | asm volatile( > > > | ^~~ > > > ./arch/s390/include/asm/cpacf.h:179:2: error: impossible constraint in 'asm' > > > > > > ... > > > > > > I am wondering how is it possible that none of the build-testing > > > infrastructure we have running against linux-next caught this? Not enough > > > non-x86 coverage? > > > > Well, there is plenty of s390 coverage with respect to daily builds > > (also here). It doesn't fail for me with gcc 9.1; so you may either > > have a different gcc version or different config options(?) so the > > compiler decided to not inline the function. > > I think I found the reason: we only hit the build failure with one > special config used for zfcpdump which has > > CONFIG_CC_OPTIMIZE_FOR_SIZE=y > > When I switched to CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE=y (which we have > in other s390x configs and which most people probably prefer), the build > does not fail even without the patch. Yes, with CONFIG_CC_OPTIMIZE_FOR_SIZE=y I can see plenty of _additional_ compile failures on s390 with "defconfig". Will fix them all... Thanks for reporting!