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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 91EA0C25B0C for ; Wed, 10 Aug 2022 02:25:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229963AbiHJCTf (ORCPT ); Tue, 9 Aug 2022 22:19:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59018 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229460AbiHJCTd (ORCPT ); Tue, 9 Aug 2022 22:19:33 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 357F165831 for ; Tue, 9 Aug 2022 19:19:32 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1660097971; 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=XsWDjZjgsNfjUxr0LgY37t8NCq9KD2p+0KhKiqkyXmI=; b=Veg4BqEoi33BjpUf6IwixZgrKtSZ6ivc3Vjp/FmFsCUxieCbXoKHZNhSo9oAIY9eNVsCKb KLZDaoEJXnSMAdRFuvPoWg1VZDigMHozsa/StsbWbXArLhmDr40NzhFUFD6ulfqIxjyqKH mrI+m6cKsl5glcqjQyvktZNcX7EPIKc= 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-13-43TqtEO5OVeMSC6f11rkWQ-1; Tue, 09 Aug 2022 22:19:30 -0400 X-MC-Unique: 43TqtEO5OVeMSC6f11rkWQ-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.rdu2.redhat.com [10.11.54.1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 7C80A1824602; Wed, 10 Aug 2022 02:19:29 +0000 (UTC) Received: from localhost (ovpn-12-32.pek2.redhat.com [10.72.12.32]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 3990740CFD0A; Wed, 10 Aug 2022 02:19:27 +0000 (UTC) Date: Wed, 10 Aug 2022 10:19:23 +0800 From: Baoquan He To: Michal Hocko Cc: Christoph Hellwig , Andrew Morton , John Donnelly , David Hildenbrand , linux-mm@kvack.org, LKML Subject: Re: [PATCH] dma/pool: do not complain if DMA pool is not allocated Message-ID: <20220810021923.GD373960@MiWiFi-R3L-srv> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Scanned-By: MIMEDefang 2.84 on 10.11.54.1 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 08/09/22 at 05:37pm, Michal Hocko wrote: > Here we go again. > --- > From 1dc9d7504624b273de47a88a9907f43533bfe08e Mon Sep 17 00:00:00 2001 > From: Michal Hocko > Date: Fri, 25 Mar 2022 13:25:59 +0100 > Subject: [PATCH] dma/pool: do not complain if DMA pool is not allocated > > we have a system complainging about order-10 allocation for the DMA pool. > > [ 14.017417][ T1] swapper/0: page allocation failure: order:10, mode:0xcc1(GFP_KERNEL|GFP_DMA), nodemask=(null),cpuset=/,mems_allowed=0-7 > [ 14.017429][ T1] CPU: 4 PID: 1 Comm: swapper/0 Not tainted 5.14.21-150400.22-default #1 SLE15-SP4 0b6a6578ade2de5c4a0b916095dff44f76ef1704 > [ 14.017434][ T1] Hardware name: XXXX > [ 14.017437][ T1] Call Trace: > [ 14.017444][ T1] > [ 14.017449][ T1] dump_stack_lvl+0x45/0x57 > [ 14.017469][ T1] warn_alloc+0xfe/0x160 > [ 14.017490][ T1] __alloc_pages_slowpath.constprop.112+0xc27/0xc60 > [ 14.017497][ T1] ? rdinit_setup+0x2b/0x2b > [ 14.017509][ T1] ? rdinit_setup+0x2b/0x2b > [ 14.017512][ T1] __alloc_pages+0x2d5/0x320 > [ 14.017517][ T1] alloc_page_interleave+0xf/0x70 > [ 14.017531][ T1] atomic_pool_expand+0x4a/0x200 > [ 14.017541][ T1] ? rdinit_setup+0x2b/0x2b > [ 14.017544][ T1] __dma_atomic_pool_init+0x44/0x90 > [ 14.017556][ T1] dma_atomic_pool_init+0xad/0x13f > [ 14.017560][ T1] ? __dma_atomic_pool_init+0x90/0x90 > [ 14.017562][ T1] do_one_initcall+0x41/0x200 > [ 14.017581][ T1] kernel_init_freeable+0x236/0x298 > [ 14.017589][ T1] ? rest_init+0xd0/0xd0 > [ 14.017596][ T1] kernel_init+0x16/0x120 > [ 14.017599][ T1] ret_from_fork+0x22/0x30 > [ 14.017604][ T1] > [...] > [ 14.018026][ T1] Node 0 DMA free:160kB boost:0kB min:0kB low:0kB high:0kB reserved_highatomic:0KB active_anon:0kB inactive_anon:0kB active_file:0kB inactive_file:0kB unevictable:0kB writepending:0kB present:15996kB managed:15360kB mlocked:0kB bounce:0kB free_pcp:0kB local_pcp:0kB free_cma:0kB > [ 14.018035][ T1] lowmem_reserve[]: 0 0 0 0 0 > [ 14.018339][ T1] Node 0 DMA: 0*4kB 0*8kB 0*16kB 1*32kB (U) 0*64kB 1*128kB (U) 0*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB = 160kB > > The usable memory in the DMA zone is obviously too small for the pool > pre-allocation. The allocation failure raises concern by admins because > this is considered an error state. > > In fact the preallocation itself doesn't expose any actual problem. It > is not even clear whether anybody is ever going to use this pool. If yes > then a warning will be triggered anyway. > > Silence the warning to prevent confusion and bug reports. LGTM, Reviewed-by: Baoquan He > > Signed-off-by: Michal Hocko > --- > kernel/dma/pool.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/kernel/dma/pool.c b/kernel/dma/pool.c > index 4d40dcce7604..1bf6de398986 100644 > --- a/kernel/dma/pool.c > +++ b/kernel/dma/pool.c > @@ -205,7 +205,7 @@ static int __init dma_atomic_pool_init(void) > ret = -ENOMEM; > if (has_managed_dma()) { > atomic_pool_dma = __dma_atomic_pool_init(atomic_pool_size, > - GFP_KERNEL | GFP_DMA); > + GFP_KERNEL | GFP_DMA | __GFP_NOWARN); > if (!atomic_pool_dma) > ret = -ENOMEM; > } > -- > 2.30.2 > > -- > Michal Hocko > SUSE Labs >