From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757027AbZKMTJz (ORCPT ); Fri, 13 Nov 2009 14:09:55 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756435AbZKMTJw (ORCPT ); Fri, 13 Nov 2009 14:09:52 -0500 Received: from mail-yw0-f202.google.com ([209.85.211.202]:44409 "EHLO mail-yw0-f202.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754570AbZKMTJw (ORCPT ); Fri, 13 Nov 2009 14:09:52 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=date:from:to:cc:subject:message-id:references:mime-version :content-type:content-disposition:in-reply-to:user-agent; b=vnChgDm3RNB7GiYWjs2CkJKK2NGq8QGHuHIvYKMRKiv/rYjI31jwFGWtAyR41UPP0D QiLZW8HR62pfm1lPxK7VL5njXLlAEou14/9gm6G+k3fNZKSvfA2nagbJgvyzC+aBLr2m 4Zo+Tpt10jj5Vg2q62LZoNgLWtGwNvpePxxbM= Date: Fri, 13 Nov 2009 22:09:55 +0300 From: Cyrill Gorcunov To: Yinghai Lu Cc: Ingo Molnar , "Maciej W. Rozycki" , x86team , LKML Subject: Re: [RFC -tip] x86,io-apic: Do not map IO-APIC direct registers twice Message-ID: <20091113190955.GC5695@lenovo> References: <20091112204852.GB5728@lenovo> <4AFC98CF.5030408@kernel.org> <20091113175057.GA5695@lenovo> <4AFDABE3.2050006@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4AFDABE3.2050006@kernel.org> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Nov 13, 2009 at 10:56:35AM -0800, Yinghai Lu wrote: > Cyrill Gorcunov wrote: > > On Thu, Nov 12, 2009 at 03:22:55PM -0800, Yinghai Lu wrote: > >> Cyrill Gorcunov wrote: > >>> Please review, I didn't manage to test (emulate actually since I don't > >>> > > ... > > > > First of all -- thanks a lot for review Yinghai! > > > >>> Also insert_resourse will not fail anymore on 1K aligned io-apics. > >> looks that we don't need that ... > >> not io_apic_base already have that + &. left problems are > >> 1. display. > >> 2. insert resource problem. > >> > >> YH > >> > >> diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c > >> index 90e8bc5..6a9379b 100644 > >> --- a/arch/x86/kernel/apic/io_apic.c > >> +++ b/arch/x86/kernel/apic/io_apic.c > >> @@ -4140,11 +4140,13 @@ fake_ioapic_page: > >> set_fixmap_nocache(idx, ioapic_phys); > >> apic_printk(APIC_VERBOSE, > >> "mapped IOAPIC to %08lx (%08lx)\n", > >> - __fix_to_virt(idx), ioapic_phys); > >> + __fix_to_virt(idx) + (ioapic_phys & ~PAGE_MASK), > > > > Don't understand, why? What is wrong with physical address, > > could you elaborate please? > > ioapic_phys could be 1k aligned, but __fix_to_virt(idx) will always return 4k aligned. yeah, I just misread your patch, I thought you've changed second argument, sorry. OK, I see what you mean, good catch, thanks! > > > > >> + ioapic_phys); > >> idx++; > >> > >> + /* spec says size is 1024 */ > > > > Hmm, MP says nothing about size of IO-APIC direct registers > > cound and as a result -- the size of MMIO. It will (and > > is) differ between IO-APIC versions. An example -- IO-APIC EOI register > > which 82489DX just dont have at all. At moment (ICH-10) the lenght is 68 > > bytes so you may note the comment in the former patch that we "hope" such > > a size will be enough for quite a long time to cover all direct register > > space an IO-APIC provides (though to be precise from this 68 bytes only > > index,data,eoi registers specified). > > > >> ioapic_res->start = ioapic_phys; > >> - ioapic_res->end = ioapic_phys + PAGE_SIZE-1; > >> + ioapic_res->end = ioapic_phys + (1<<10) - 1; > >> ioapic_res++; > >> } > >> } > >> > > > > I think I've compicated the patch/idea too much indeed :) > > Since we have fixmap for all io_apics build time reserved > > even if some io-apic is 1K aligned we still may use new > > fixmap index. So only issue remains -- resource allocation. > > Here is an updated patch. Please review. > > 2. print out ...? Print out what? Not sure I understand you right. Perhaps you mean to check insert_resourse results? > > YH > -- Cyrill