Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933165AbbFWOvK (ORCPT ); Tue, 23 Jun 2015 10:51:10 -0400 Received: from smtp02.citrix.com ([66.165.176.63]:3939 "EHLO SMTP02.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933039AbbFWOvE (ORCPT ); Tue, 23 Jun 2015 10:51:04 -0400 X-IronPort-AV: E=Sophos;i="5.13,666,1427760000"; d="scan'208";a="277718420" Date: Tue, 23 Jun 2015 15:49:49 +0100 From: Stefano Stabellini X-X-Sender: sstabellini@kaball.uk.xensource.com To: Julien Grall CC: Stefano Stabellini , Russell King , , , , , Subject: Re: [RFC 23/23] arm/xen: Add support for 64KB page granularity In-Reply-To: <55896F2D.5030405@citrix.com> Message-ID: References: <1431622863-28575-1-git-send-email-julien.grall@citrix.com> <1431622863-28575-24-git-send-email-julien.grall@citrix.com> <55896F2D.5030405@citrix.com> User-Agent: Alpine 2.02 (DEB 1266 2009-07-14) MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" X-DLP: MIA1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2333 Lines: 57 On Tue, 23 Jun 2015, Julien Grall wrote: > Hi, > > On 23/06/15 15:19, Stefano Stabellini wrote: > >> diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c > >> index 224081c..dcfe251 100644 > >> --- a/arch/arm/xen/enlighten.c > >> +++ b/arch/arm/xen/enlighten.c > >> @@ -93,8 +93,8 @@ static void xen_percpu_init(void) > >> pr_info("Xen: initializing cpu%d\n", cpu); > >> vcpup = per_cpu_ptr(xen_vcpu_info, cpu); > >> > >> - info.mfn = __pa(vcpup) >> PAGE_SHIFT; > >> - info.offset = offset_in_page(vcpup); > >> + info.mfn = __pa(vcpup) >> XEN_PAGE_SHIFT; > >> + info.offset = xen_offset_in_page(vcpup); > >> > >> err = HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_info, cpu, &info); > >> BUG_ON(err); > >> @@ -204,7 +204,7 @@ static int __init xen_guest_init(void) > >> xatp.domid = DOMID_SELF; > >> xatp.idx = 0; > >> xatp.space = XENMAPSPACE_shared_info; > >> - xatp.gpfn = __pa(shared_info_page) >> PAGE_SHIFT; > >> + xatp.gpfn = __pa(shared_info_page) >> XEN_PAGE_SHIFT; > >> if (HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp)) > >> BUG(); > > > > What about xen_remap_domain_mfn_range? I guess we don't support that use > > case on 64K guests? If so, I would appreaciate an assert and/or an error > > message. > > The implementation of xen_remap_domain_mfn_range return -ENOSYS no > matter the page granularity. > > This function is PV specific and has been added few months ago just for > a stub. See comment in the code: > "/* Not used by XENFEAT_auto_translated guests */" > > Any logging/BUG_ON within this function is out of scope for this series. > And I don't think this will be really useful. Feel free to send a patch > for it. Yes, you are right, I was reading an older version of Linux that still had xen_remap_domain_mfn_range properly implemented. The new function is called xen_remap_domain_mfn_array which calls xen_xlate_remap_gfn_array. I'll rephrase my question then: What about xen_remap_domain_mfn_array? I guess we don't support that use case on 64K guests? If so, I would appreaciate an assert and/or an error message. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/