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 4CF3BC04A95 for ; Tue, 25 Oct 2022 10:39:44 +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=3n4mI/yVWb9vYBKGpkFSJvmPJKkjfTJ8O8psVDnlkrA=; b=XyR363A7Gqs1ye SKNGOETiiGUhgUJVyWb42QzAk9rUO8K/IdX6H/Xq3F8qY4WuGPrqWN+OAmwrERA38IlzddNlGCEUY 7fY9UwYOU3SlNNBRs9QdL9sU3R0vemCHQeIr0JswXPHPrrevsdiJGbSWcxJBqMdQ8QH2ctCsWnsxv UUtvlch3x9D6ynNf4xl2r2MBkpO/ZDnjo8/ybnl5N8WMFFrQeWy3F1nfgB6lXqsVGABOghs6mvljI 3nyguCjii2ncp0bkpeDFeTcV2W2qBXnPqPYxCeDGcJViDQ1xc2NFrNXho2827nOTORA0svAvS1HUj JQtyqwU+8kfUWw/IzRiw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1onHLP-004pGr-8S; Tue, 25 Oct 2022 10:39:39 +0000 Received: from mail.skyhub.de ([5.9.137.197]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1onHLM-004pFm-9u for kexec@lists.infradead.org; Tue, 25 Oct 2022 10:39:37 +0000 Received: from zn.tnic (p200300ea9733e753329c23fffea6a903.dip0.t-ipconnect.de [IPv6:2003:ea:9733:e753:329c:23ff:fea6:a903]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.skyhub.de (SuperMail on ZX Spectrum 128k) with ESMTPSA id 77F211EC04CB; Tue, 25 Oct 2022 12:39:34 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1666694374; 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: content-transfer-encoding:in-reply-to:in-reply-to: references:references; bh=bJEdtbRqgdbjhqUqDGLu9oDkYSzHvDi/vH6BXxoFAh8=; b=JxIF5aD8t+drPh0XyHi/aIDkukRMN7v+nUHqpoC0kztFZF/DC3CYHhIjv8G0wKaXyWcgJ2 NJswHW8qF/0qgkCUBTscjqoybTkfq7npVh1L77t2FH8Z+j9aYvMn2i6v+EnvcLXRHTv8xn 0ypbB4muvtXV4mgjUbabEqF3ztjeN8Y= Date: Tue, 25 Oct 2022 12:39:34 +0200 From: Borislav Petkov To: Eric DeVolder Cc: Oscar Salvador , Andrew Morton , david@redhat.com, linux-kernel@vger.kernel.org, x86@kernel.org, kexec@lists.infradead.org, ebiederm@xmission.com, dyoung@redhat.com, bhe@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, sourabhjain@linux.ibm.com, linux-mm@kvack.org Subject: Re: [PATCH v12 7/7] x86/crash: Add x86 crash hotplug support Message-ID: References: <20220909210509.6286-1-eric.devolder@oracle.com> <20220909210509.6286-8-eric.devolder@oracle.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20221025_033936_523342_0C999CB4 X-CRM114-Status: GOOD ( 12.73 ) 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 Wed, Oct 12, 2022 at 11:20:59AM -0500, Eric DeVolder wrote: > I once had CONFIG_CRASH_HOTPLUG, but you disagreed. > > https://lore.kernel.org/lkml/Ylgot+LUDQl+G%2F5N@zn.tnic/ > > From there I simply went with > > #if defined(CONFIG_HOTPLUG_CPU) || defined(CONFIG_MEMORY_HOTPLUG) > > which route do you prefer? If you do a single Kconfig item which depends on those two, it probably is cleaner this way. And if the max memory ranges are hardcoded you don't need the other prompt asking the user something she most likely doesn't know how to answer properly. That is, unless you wanna have that crash hotplug built in all the time. Because CONFIG_HOTPLUG_CPU is pretty much always enabled so you might just as well add the crash hotplug support unconditionally, without any Kconfig ifdeffery whatsoever except CONFIG_MEMORY_HOTPLUG as that is special and not present on the majority of hardware. But on a plain simple laptop or workstation which has CPU hotplug, would it make sense for the crash ranges to get updated too when CPUs are offlined? If so, I think you want this code present there too, without a Kconfig item. If this is server-only anyway, then a single Kconfig item sounds like not such a bad idea. I hope that makes some sense. -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec