From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ed1-f72.google.com (mail-ed1-f72.google.com [209.85.208.72]) by kanga.kvack.org (Postfix) with ESMTP id BF4EB6B2EB0 for ; Fri, 24 Aug 2018 04:29:10 -0400 (EDT) Received: by mail-ed1-f72.google.com with SMTP id y8-v6so3202319edr.12 for ; Fri, 24 Aug 2018 01:29:10 -0700 (PDT) Received: from mx1.suse.de (mx2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id m31-v6si437782edd.103.2018.08.24.01.29.09 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 24 Aug 2018 01:29:09 -0700 (PDT) Date: Fri, 24 Aug 2018 10:29:08 +0200 From: Michal Hocko Subject: Re: [PATCH 1/2] Revert "x86/e820: put !E820_TYPE_RAM regions into memblock.reserved" Message-ID: <20180824082908.GC29735@dhcp22.suse.cz> References: <20180823182513.8801-1-msys.mizuma@gmail.com> <20180824000325.GA20143@hori1.linux.bs1.fc.nec.co.jp> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180824000325.GA20143@hori1.linux.bs1.fc.nec.co.jp> Sender: owner-linux-mm@kvack.org List-ID: To: Naoya Horiguchi Cc: Masayoshi Mizuma , "linux-mm@kvack.org" , Masayoshi Mizuma , "linux-kernel@vger.kernel.org" , "x86@kernel.org" , "osalvador@techadventures.net" , Pavel Tatashin On Fri 24-08-18 00:03:25, Naoya Horiguchi wrote: > (CCed related people) Fixup Pavel email. > > Hi Mizuma-san, > > Thank you for the report. > The mentioned patch was created based on feedbacks from reviewers/maintainers, > so I'd like to hear from them about how we should handle the issue. > > And one note is that there is a follow-up patch for "x86/e820: put !E820_TYPE_RAM > regions into memblock.reserved" which might be affected by your changes. > > > commit e181ae0c5db9544de9c53239eb22bc012ce75033 > > Author: Pavel Tatashin > > Date: Sat Jul 14 09:15:07 2018 -0400 > > > > mm: zero unavailable pages before memmap init > > Thanks, > Naoya Horiguchi > > On Thu, Aug 23, 2018 at 02:25:12PM -0400, Masayoshi Mizuma wrote: > > From: Masayoshi Mizuma > > > > commit 124049decbb1 ("x86/e820: put !E820_TYPE_RAM regions into > > memblock.reserved") breaks movable_node kernel option because it > > changed the memory gap range to reserved memblock. So, the node > > is marked as Normal zone even if the SRAT has Hot plaggable affinity. > > > > ===================================================================== > > kernel: BIOS-e820: [mem 0x0000180000000000-0x0000180fffffffff] usable > > kernel: BIOS-e820: [mem 0x00001c0000000000-0x00001c0fffffffff] usable > > ... > > kernel: reserved[0x12]#011[0x0000181000000000-0x00001bffffffffff], 0x000003f000000000 bytes flags: 0x0 > > ... > > kernel: ACPI: SRAT: Node 2 PXM 6 [mem 0x180000000000-0x1bffffffffff] hotplug > > kernel: ACPI: SRAT: Node 3 PXM 7 [mem 0x1c0000000000-0x1fffffffffff] hotplug > > ... > > kernel: Movable zone start for each node > > kernel: Node 3: 0x00001c0000000000 > > kernel: Early memory node ranges > > ... > > ===================================================================== > > > > Naoya's v1 patch [*] fixes the original issue and this movable_node > > issue doesn't occur. > > Let's revert commit 124049decbb1 ("x86/e820: put !E820_TYPE_RAM > > regions into memblock.reserved") and apply the v1 patch. > > > > [*] https://lkml.org/lkml/2018/6/13/27 > > > > Signed-off-by: Masayoshi Mizuma > > --- > > arch/x86/kernel/e820.c | 15 +++------------ > > 1 file changed, 3 insertions(+), 12 deletions(-) > > > > diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c > > index c88c23c658c1..d1f25c831447 100644 > > --- a/arch/x86/kernel/e820.c > > +++ b/arch/x86/kernel/e820.c > > @@ -1248,7 +1248,6 @@ void __init e820__memblock_setup(void) > > { > > int i; > > u64 end; > > - u64 addr = 0; > > > > /* > > * The bootstrap memblock region count maximum is 128 entries > > @@ -1265,21 +1264,13 @@ void __init e820__memblock_setup(void) > > struct e820_entry *entry = &e820_table->entries[i]; > > > > end = entry->addr + entry->size; > > - if (addr < entry->addr) > > - memblock_reserve(addr, entry->addr - addr); > > - addr = end; > > if (end != (resource_size_t)end) > > continue; > > > > - /* > > - * all !E820_TYPE_RAM ranges (including gap ranges) are put > > - * into memblock.reserved to make sure that struct pages in > > - * such regions are not left uninitialized after bootup. > > - */ > > if (entry->type != E820_TYPE_RAM && entry->type != E820_TYPE_RESERVED_KERN) > > - memblock_reserve(entry->addr, entry->size); > > - else > > - memblock_add(entry->addr, entry->size); > > + continue; > > + > > + memblock_add(entry->addr, entry->size); > > } > > > > /* Throw away partial pages: */ > > -- > > 2.18.0 > > > > -- Michal Hocko SUSE Labs