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=-2.5 required=3.0 tests=MAILING_LIST_MULTI,SPF_PASS, URIBL_BLOCKED,USER_AGENT_MUTT 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 E600AC3279B for ; Wed, 4 Jul 2018 12:36:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9DC4922501 for ; Wed, 4 Jul 2018 12:36:36 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9DC4922501 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934636AbeGDMgc (ORCPT ); Wed, 4 Jul 2018 08:36:32 -0400 Received: from mx2.suse.de ([195.135.220.15]:46520 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S934117AbeGDMga (ORCPT ); Wed, 4 Jul 2018 08:36:30 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id F2F08AD9E; Wed, 4 Jul 2018 12:36:27 +0000 (UTC) Date: Wed, 4 Jul 2018 14:36:27 +0200 From: Michal Hocko To: Vlastimil Babka Cc: Geert Uytterhoeven , Mike Rapoport , Greg Ungerer , Sam Creasey , linux-m68k , Linux MM , Linux Kernel Mailing List Subject: Re: [PATCH v2 3/3] m68k: switch to MEMBLOCK + NO_BOOTMEM Message-ID: <20180704123627.GM22503@dhcp22.suse.cz> References: <1530685696-14672-1-git-send-email-rppt@linux.vnet.ibm.com> <1530685696-14672-4-git-send-email-rppt@linux.vnet.ibm.com> <20180704075410.GF22503@dhcp22.suse.cz> <89f48f7a-6cbf-ac9a-cacc-cd3ca79f8c66@suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <89f48f7a-6cbf-ac9a-cacc-cd3ca79f8c66@suse.cz> User-Agent: Mutt/1.10.0 (2018-05-17) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org [CC Andrew - email thread starts http://lkml.kernel.org/r/1530685696-14672-1-git-send-email-rppt@linux.vnet.ibm.com] OK, so here we go with the full patch. >From 0e8432b875d98a7a0d3f757fce2caa8d16a8de15 Mon Sep 17 00:00:00 2001 From: Michal Hocko Date: Wed, 4 Jul 2018 14:31:46 +0200 Subject: [PATCH] memblock: do not complain about top-down allocations for !MEMORY_HOTREMOVE Mike Rapoport is converting architectures from bootmem to noboodmem allocator. While doing so for m68k Geert has noticed that he gets a scary looking warning WARNING: CPU: 0 PID: 0 at mm/memblock.c:230 memblock_find_in_range_node+0x11c/0x1be memblock: bottom-up allocation failed, memory hotunplug may be affected Modules linked in: CPU: 0 PID: 0 Comm: swapper Not tainted 4.18.0-rc3-atari-01343-gf2fb5f2e09a97a3c-dirty #7 Stack from 003c3e20: 003c3e20 0039cf44 00023800 00433000 ffffffff 00001000 00240000 000238aa 00378734 000000e6 004285ac 00000009 00000000 003c3e58 003787c0 003c3e74 003c3ea4 004285ac 00378734 000000e6 003787c0 00000000 00000000 00000001 00000000 00000010 00000000 00428490 003e3856 ffffffff ffffffff 003c3ed0 00044620 003c3ee0 00417a10 00240000 00000010 00000000 00000000 00000001 00000000 00000001 00240000 00000000 00000000 00000000 00001000 003e3856 Call Trace: [<00023800>] __warn+0xa8/0xc2 [<00001000>] kernel_pg_dir+0x0/0x1000 [<00240000>] netdev_lower_get_next+0x2/0x22 [<000238aa>] warn_slowpath_fmt+0x2e/0x36 [<004285ac>] memblock_find_in_range_node+0x11c/0x1be [<004285ac>] memblock_find_in_range_node+0x11c/0x1be [<00428490>] memblock_find_in_range_node+0x0/0x1be [<00044620>] vprintk_func+0x66/0x6e [<00417a10>] memblock_virt_alloc_internal+0xd0/0x156 [<00240000>] netdev_lower_get_next+0x2/0x22 [<00240000>] netdev_lower_get_next+0x2/0x22 [<00001000>] kernel_pg_dir+0x0/0x1000 [<00417b8c>] memblock_virt_alloc_try_nid_nopanic+0x58/0x7a [<00240000>] netdev_lower_get_next+0x2/0x22 [<00001000>] kernel_pg_dir+0x0/0x1000 [<00001000>] kernel_pg_dir+0x0/0x1000 [<00010000>] EXPTBL+0x234/0x400 [<00010000>] EXPTBL+0x234/0x400 [<002f3644>] alloc_node_mem_map+0x4a/0x66 [<00240000>] netdev_lower_get_next+0x2/0x22 [<004155ca>] free_area_init_node+0xe2/0x29e [<00010000>] EXPTBL+0x234/0x400 [<00411392>] paging_init+0x430/0x462 [<00001000>] kernel_pg_dir+0x0/0x1000 [<000427cc>] printk+0x0/0x1a [<00010000>] EXPTBL+0x234/0x400 [<0041084c>] setup_arch+0x1b8/0x22c [<0040e020>] start_kernel+0x4a/0x40a [<0040d344>] _sinittext+0x344/0x9e8 The warning is basically saying that a top-down allocation can break memory hotremove because memblock allocation is not movable. But m68k doesn't even support MEMORY_HOTREMOVE is there is no point to warn about it. Make the warning conditional only to configurations that care. Reported-by: Geert Uytterhoeven Tested-by: Geert Uytterhoeven Signed-off-by: Michal Hocko --- mm/memblock.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/mm/memblock.c b/mm/memblock.c index 03d48d8835ba..2acec4033389 100644 --- a/mm/memblock.c +++ b/mm/memblock.c @@ -227,7 +227,8 @@ phys_addr_t __init_memblock memblock_find_in_range_node(phys_addr_t size, * so we use WARN_ONCE() here to see the stack trace if * fail happens. */ - WARN_ONCE(1, "memblock: bottom-up allocation failed, memory hotunplug may be affected\n"); + WARN_ONCE(IS_ENABLED(CONFIG_MEMORY_HOTREMOVE), + "memblock: bottom-up allocation failed, memory hotremove may be affected\n"); } return __memblock_find_range_top_down(start, end, size, align, nid, -- 2.18.0 -- Michal Hocko SUSE Labs