From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id F34B4C6FD18 for ; Wed, 19 Apr 2023 00:05:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=wZ8Umk+aXtUqXSfZ1jHCksvh1u6G39+zl2llqfjaBeo=; b=jNWEtkB5p4J9FK F8nDxPDZ9ApEuGzA6hfYCBfOfcHQyEmYa87cCBzbEP5SFaMpmJ7U2xQHKXHYd/Tn03dxi4CgAmYFs POAiASf19FmAUza3X2NIJNMswSfkjFO+8SC2Z3+gttkri5JK6ODZDN5kVOtjsQzBe43hjPw/NS7mb UwENAp7OAs/6uspN8cF44hGGzJGIeirwzk/JHCUqGja5NGZVZinXbjANZ9tn2257IXkYiBfedStjk jEKyWfqS1pviiVLaN4iUGifAwhBLNZp9qcMlLjkhJuPeL/q5JzRxG5wtD713ypo5cNEGIeA53Z1BE wzHzo6OFhsVZmi6xganQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1povKH-003cxm-20; Wed, 19 Apr 2023 00:05:33 +0000 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1povKC-003cx4-1T for kexec@lists.infradead.org; Wed, 19 Apr 2023 00:05:30 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1681862725; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=iqYcQJ7RxHLqq2m5mcHetAO2yttoUlP/01PDG9Z2dnM=; b=h2q2iIt/FqmMw5DMh4+BJT3Fj9Ee6vWwRfm0D3BvgmRFT9ZXK0OfefUoRedG7Tnwx4h2iX dnZ5G4pK4TfaKCKcmsCn+1+P0sC/VSNlWAblC+HGC/jIVKtmvQ8QrgkU11epPNYCHUad91 e4VEaFMhXRGhz58fWVwWE5mkmDZSDi8= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-618-lhN3jzYlOMG7_cdy7DrwjA-1; Tue, 18 Apr 2023 20:05:22 -0400 X-MC-Unique: lhN3jzYlOMG7_cdy7DrwjA-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 81B788996E0; Wed, 19 Apr 2023 00:05:21 +0000 (UTC) Received: from localhost (ovpn-12-26.pek2.redhat.com [10.72.12.26]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 434E12958; Wed, 19 Apr 2023 00:05:20 +0000 (UTC) Date: Wed, 19 Apr 2023 08:05:16 +0800 From: Baoquan He To: Eric DeVolder , bp@alien8.de, x86@kernel.org Cc: linux-kernel@vger.kernel.org, kexec@lists.infradead.org, ebiederm@xmission.com, dyoung@redhat.com, vgoyal@redhat.com, tglx@linutronix.de, mingo@redhat.com, dave.hansen@linux.intel.com, hpa@zytor.com, nramas@linux.microsoft.com, thomas.lendacky@amd.com, robh@kernel.org, efault@gmx.de, rppt@kernel.org, david@redhat.com, sourabhjain@linux.ibm.com, konrad.wilk@oracle.com, boris.ostrovsky@oracle.com Subject: Re: [PATCH v21 2/7] crash: add generic infrastructure for crash hotplug support Message-ID: References: <20230404180326.6890-1-eric.devolder@oracle.com> <20230404180326.6890-3-eric.devolder@oracle.com> <80767ccc-ffd4-9cb9-44e4-a8d4f0e13853@oracle.com> <7b25449b-72e9-3eca-73a9-592d7400b746@oracle.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <7b25449b-72e9-3eca-73a9-592d7400b746@oracle.com> X-Scanned-By: MIMEDefang 3.1 on 10.11.54.5 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230418_170528_584707_23D27C3D X-CRM114-Status: GOOD ( 36.45 ) X-BeenThere: kexec@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "kexec" Errors-To: kexec-bounces+kexec=archiver.kernel.org@lists.infradead.org On 04/18/23 at 08:55am, Eric DeVolder wrote: ...... > > > > Seems we passed in the cpu number just for printing here. Wondering why > > > > we don't print out hot added/removed memory ranges. Is the cpu number > > > > printing necessary? > > > > > > > Baoquan, > > > > > > Ah, actually until recently it was used to track the 'offlinecpu' in this > > > function, but tglx pointed out that was un-necessary. That resulted in > > > dropping the code in this function dealing with offlinecpu, leaving this as > > > its only use in this function. > > > > > > The printing of cpu number is not necessary, but helpful; I use it for debugging. > > > > OK, I see. I am not requesting memory range printing, just try to prove > > cpu number printing is not so justified. If it's helpful, I am OK with > > it. Let's see if other people have concern about this. > > > > I do not plan on adding the memory range printing. > > > > > > > The printing of memory range is also not necessary, but in order to do that, > > > should we choose to do so, requires passing in the memory range to this > > > function. This patch series did do this early on, and by v7 I dropped it at > > > your urging (https://lore.kernel.org/lkml/20220401183040.1624-1-eric.devolder@oracle.com/). > > > At the time, I provided it since I considered this generic infrastructure, > > > but I could not defend it since x86 didn't need it. However, PPC now needs > > > this, and is now carrying this as part of PPC support of CRASH_HOTPLUG (https://lore.kernel.org/linuxppc-dev/20230312181154.278900-6-sourabhjain@linux.ibm.com/T/#u). > > > > > > If you'd rather I pickup the memory range handling again, I can do that. I > > > think I'd likely change this function to be: > > > > > > void crash_handle_hotplug_event(unsigned int hp_action, unsigned int cpu, > > > struct memory_notify *mhp); > > > > > > where on a CPU op the 'cpu' parameter would be valid and 'mhp' NULL, and on a memory op, > > > the 'mhp' would be valid and 'cpu' parameter invalid(0). > > > > > > I'd likely then stuff these two parameters into struct kimage so that it can > > > be utilized by arch-specific handler, if needed. > > > > > > And of course, would print out the memory range for debug purposes. > > > > > > Let me know what you think. > > > > I do not plan on adding the memory range handling; I'll let Sourabh do that as he has a use case for it. > > As such, I don't see any other request for changes. OK, then I have no concern about this patchset. Thanks a lot for all these effort, Eric. Hi x86 maintainers, Could you help check if there's anything we need improve, or consider taking this patchset? Thanks Baoquan _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec