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 X-Spam-Level: X-Spam-Status: No, score=-17.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_RED,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0ACD1C433DB for ; Tue, 23 Mar 2021 14:33:36 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id A8440619B1 for ; Tue, 23 Mar 2021 14:33:35 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A8440619B1 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 1E0866B01A8; Tue, 23 Mar 2021 10:33:35 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 1B6FF6B01AA; Tue, 23 Mar 2021 10:33:35 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 058626B01AB; Tue, 23 Mar 2021 10:33:34 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0160.hostedemail.com [216.40.44.160]) by kanga.kvack.org (Postfix) with ESMTP id DE9C66B01A8 for ; Tue, 23 Mar 2021 10:33:34 -0400 (EDT) Received: from smtpin11.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 9CDF9824999B for ; Tue, 23 Mar 2021 14:33:34 +0000 (UTC) X-FDA: 77951382348.11.3AEABCF Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [63.128.21.124]) by imf10.hostedemail.com (Postfix) with ESMTP id AFE9C40B8CC7 for ; Tue, 23 Mar 2021 14:33:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1616510003; 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=QvoP2f+nB/4FZFCRnx7s5l2cyw/nZg7tcWFs3fUsWM4=; b=a5L4WKXbQ5VhVLN2Oe4kEdgU/QLJDbuqv8RZp6g4RC5UDlTBJ7I6qY7w8ktsxXoiyH18ZC h6HmyggIGt4r+Z14Su3WdPWLqyeY9+cT/fwFKSeiyxDIxBWYat5CCpOBZiT6ep42CMl7ZY TcEQwTllDbbVXDlPgTDDPFklGamztQ4= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-430-LQEUgcSuOYKYFPPElPHZ3Q-1; Tue, 23 Mar 2021 10:33:21 -0400 X-MC-Unique: LQEUgcSuOYKYFPPElPHZ3Q-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 655641B18BD3; Tue, 23 Mar 2021 14:33:17 +0000 (UTC) Received: from localhost (ovpn-13-5.pek2.redhat.com [10.72.13.5]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 4D41C1972B; Tue, 23 Mar 2021 14:33:06 +0000 (UTC) Date: Tue, 23 Mar 2021 22:33:03 +0800 From: Baoquan He To: David Hildenbrand Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, Andrew Morton , Greg Kroah-Hartman , Dan Williams , Daniel Vetter , Andy Shevchenko , Mauro Carvalho Chehab , Dave Young , Vivek Goyal , Dave Hansen , Keith Busch , Michal Hocko , Qian Cai , Oscar Salvador , Eric Biederman , Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H. Peter Anvin" , Tom Lendacky , Brijesh Singh , x86@kernel.org, kexec@lists.infradead.org Subject: Re: [PATCH v1 1/3] kernel/resource: make walk_system_ram_res() find all busy IORESOURCE_SYSTEM_RAM resources Message-ID: <20210323143303.GC13786@MiWiFi-R3L-srv> References: <20210322160200.19633-1-david@redhat.com> <20210322160200.19633-2-david@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210322160200.19633-2-david@redhat.com> User-Agent: Mutt/1.10.1 (2018-07-13) X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: AFE9C40B8CC7 X-Stat-Signature: de6zsp9qq8b9uqahs6e1xaa5phaqn771 Received-SPF: none (redhat.com>: No applicable sender policy available) receiver=imf10; identity=mailfrom; envelope-from=""; helo=us-smtp-delivery-124.mimecast.com; client-ip=63.128.21.124 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1616510008-924658 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 03/22/21 at 05:01pm, David Hildenbrand wrote: > It used to be true that we can have busy system RAM only on the first level > in the resourc tree. However, this is no longer holds for driver-managed > system RAM (i.e., added via dax/kmem and virtio-mem), which gets added on > lower levels. > > We have two users of walk_system_ram_res(), which currently only > consideres the first level: > a) kernel/kexec_file.c:kexec_walk_resources() -- We properly skip > IORESOURCE_SYSRAM_DRIVER_MANAGED resources via > locate_mem_hole_callback(), so even after this change, we won't be > placing kexec images onto dax/kmem and virtio-mem added memory. No > change. > b) arch/x86/kernel/crash.c:fill_up_crash_elf_data() -- we're currently > not adding relevant ranges to the crash elf info, resulting in them > not getting dumped via kdump. > > This change fixes loading a crashkernel via kexec_file_load() and including > dax/kmem and virtio-mem added System RAM in the crashdump on x86-64. Note > that e.g,, arm64 relies on memblock data and, therefore, always considers > all added System RAM already. > > Let's find all busy IORESOURCE_SYSTEM_RAM resources, making the function > behave like walk_system_ram_range(). > > Cc: Andrew Morton > Cc: Greg Kroah-Hartman > Cc: Dan Williams > Cc: Daniel Vetter > Cc: Andy Shevchenko > Cc: Mauro Carvalho Chehab > Cc: Signed-off-by: David Hildenbrand > Cc: Dave Young > Cc: Baoquan He > Cc: Vivek Goyal > Cc: Dave Hansen > Cc: Keith Busch > Cc: Michal Hocko > Cc: Qian Cai > Cc: Oscar Salvador > Cc: Eric Biederman > Cc: Thomas Gleixner > Cc: Ingo Molnar > Cc: Borislav Petkov > Cc: "H. Peter Anvin" > Cc: Tom Lendacky > Cc: Brijesh Singh > Cc: x86@kernel.org > Cc: kexec@lists.infradead.org > Signed-off-by: David Hildenbrand > --- > kernel/resource.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/kernel/resource.c b/kernel/resource.c > index 627e61b0c124..4efd6e912279 100644 > --- a/kernel/resource.c > +++ b/kernel/resource.c > @@ -457,7 +457,7 @@ int walk_system_ram_res(u64 start, u64 end, void *arg, > { > unsigned long flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; > > - return __walk_iomem_res_desc(start, end, flags, IORES_DESC_NONE, true, > + return __walk_iomem_res_desc(start, end, flags, IORES_DESC_NONE, false, > arg, func); Thanks, David, this is a good fix. Acked-by: Baoquan He > } > > -- > 2.29.2 >