From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from fgwmail5.fujitsu.co.jp ([192.51.44.35]) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1Vg24v-0006Hv-Do for kexec@lists.infradead.org; Tue, 12 Nov 2013 00:43:38 +0000 Received: from m1.gw.fujitsu.co.jp (unknown [10.0.50.71]) by fgwmail5.fujitsu.co.jp (Postfix) with ESMTP id ADDE83EE1DE for ; Tue, 12 Nov 2013 09:43:11 +0900 (JST) Received: from smail (m1 [127.0.0.1]) by outgoing.m1.gw.fujitsu.co.jp (Postfix) with ESMTP id 9CCBC45DE69 for ; Tue, 12 Nov 2013 09:43:11 +0900 (JST) Received: from s1.gw.fujitsu.co.jp (s1.gw.nic.fujitsu.com [10.0.50.91]) by m1.gw.fujitsu.co.jp (Postfix) with ESMTP id 78A0845DE53 for ; Tue, 12 Nov 2013 09:43:11 +0900 (JST) Received: from s1.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s1.gw.fujitsu.co.jp (Postfix) with ESMTP id 3F9C8E08009 for ; Tue, 12 Nov 2013 09:43:11 +0900 (JST) Received: from ml14.s.css.fujitsu.com (ml14.s.css.fujitsu.com [10.240.81.134]) by s1.gw.fujitsu.co.jp (Postfix) with ESMTP id E4726E08004 for ; Tue, 12 Nov 2013 09:43:10 +0900 (JST) Message-ID: <52817916.9030104@jp.fujitsu.com> Date: Tue, 12 Nov 2013 09:40:54 +0900 From: HATAYAMA Daisuke MIME-Version: 1.0 Subject: Re: [PATCH v4 1/3] x86, apic: Don't count the CPU with BP flag from MP table as booting-up CPU References: <20131022150015.24240.39686.stgit@localhost6.localdomain6> <20131022150124.24240.20741.stgit@localhost6.localdomain6> <20131108160830.GB13068@redhat.com> <5280466E.9090504@jp.fujitsu.com> <20131111165202.GD11547@redhat.com> In-Reply-To: <20131111165202.GD11547@redhat.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "kexec" Errors-To: kexec-bounces+dwmw2=twosheds.infradead.org@lists.infradead.org To: Vivek Goyal Cc: fengguang.wu@intel.com, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, bp@alien8.de, ebiederm@xmission.com, akpm@linux-foundation.org, hpa@linux.intel.com, jingbai.ma@hp.com (2013/11/12 1:52), Vivek Goyal wrote: > On Mon, Nov 11, 2013 at 11:52:30AM +0900, HATAYAMA Daisuke wrote: > > [..] >> Looking at my past investigation, kernel/mpparse.c, mm/amdtopology.c and >> platform/visws/visws_quirks.c assumes that boot_cpu_physical_apicid >> has initial apicid of the BSP, not the current actual booting-up cpu. >> >> These three are called in get_smp_config() below. If either of them is >> called actually, boot_cpu_physical_apicid has the apicid different from >> the current actual booting-up cpu temporarily. But init_apic_mappings() >> soon modifies back the value to the one obtained by read_apic_id(). >> >> /* >> * Read APIC and some other early information from ACPI tables. >> */ >> acpi_boot_init(); >> sfi_init(); >> x86_dtb_init(); >> >> /* >> * get boot-time SMP configuration: >> */ >> if (smp_found_config) >> get_smp_config(); >> >> prefill_possible_map(); >> >> init_cpu_to_node(); >> >> init_apic_mappings(); >> >> So, thanks to init_apic_mappings(), the patch set would work without the >> first patch... This is a careless point in this patch set. >> > > If init_apic_mappings(), is making sure that boot_cpu_physical_apicid is > apic id of booting processor, and you don't need first patch of your > series, then I think atleast re-post your patch series without first > patch. > Yes, I'll repost soon. > And then there can be another series which looks into whether we need > two different variables or not and if we do, then a separate variable > bsp_physical_apicid will track the bsp id as reported by BIOS and > boot_cpu_physical_apicid will track apic id of booting cpu. This might > a very big and slow cleanup. So I think blocking the first patch series > behind it might not make much sense. > Yes, the current handling of boot_cpu_physical_apicid looks strange and should be cleaned up, but the cleaning up needs reviewing together with the maintainers for the corresponding part; in particular, it can be lengthy for the reviewing on amdtopology.c. I leave this as another work for the time being. -- Thanks. HATAYAMA, Daisuke _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec