From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:21278 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726076AbfGSGc6 (ORCPT ); Fri, 19 Jul 2019 02:32:58 -0400 Received: from pps.filterd (m0098409.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x6J6RVvW058287 for ; Fri, 19 Jul 2019 02:32:57 -0400 Received: from e06smtp01.uk.ibm.com (e06smtp01.uk.ibm.com [195.75.94.97]) by mx0a-001b2d01.pphosted.com with ESMTP id 2tu4yb7vq2-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Fri, 19 Jul 2019 02:32:57 -0400 Received: from localhost by e06smtp01.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Fri, 19 Jul 2019 07:32:55 +0100 Date: Fri, 19 Jul 2019 08:32:49 +0200 From: Heiko Carstens Subject: Re: [PATCH 1/1] s390/dma: provide proper ARCH_ZONE_DMA_BITS value References: <20190718172120.69947-1-pasic@linux.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190718172120.69947-1-pasic@linux.ibm.com> Message-Id: <20190719063249.GA4852@osiris> Sender: linux-s390-owner@vger.kernel.org List-ID: To: Halil Pasic Cc: kvm@vger.kernel.org, linux-s390@vger.kernel.org, Christoph Hellwig , Vasily Gorbik , Petr Tesarik , Christian Borntraeger , Janosch Frank On Thu, Jul 18, 2019 at 07:21:20PM +0200, Halil Pasic wrote: > On s390 ZONE_DMA is up to 2G, i.e. ARCH_ZONE_DMA_BITS should be 31 bits. > The current value is 24 and makes __dma_direct_alloc_pages() take a > wrong turn first (but __dma_direct_alloc_pages() recovers then). > > Let's correct ARCH_ZONE_DMA_BITS value and avoid wrong turns. > > Signed-off-by: Halil Pasic > Reported-by: Petr Tesarik > Fixes: c61e9637340e ("dma-direct: add support for allocation from > ZONE_DMA and ZONE_DMA32") Please don't add linebreaks to "Fixes:" tags. > --- > arch/s390/include/asm/dma.h | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/arch/s390/include/asm/dma.h b/arch/s390/include/asm/dma.h > index 6f26f35d4a71..3b0329665b13 100644 > --- a/arch/s390/include/asm/dma.h > +++ b/arch/s390/include/asm/dma.h > @@ -10,6 +10,7 @@ > * by the 31 bit heritage. > */ > #define MAX_DMA_ADDRESS 0x80000000 > +#define ARCH_ZONE_DMA_BITS 31 powerpc has this in arch/powerpc/include/asm/page.h. This really should be consistently defined in the same header file across architectures. Christoph, what is the preferred header file for this definition? I'd also rather say it would be better to move the #ifndef ARCH_ZONE_DMA_BITS check to a common code header file instead of having it in a C file, and make it more obvious in which header file architectures should/can override the default, no?