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 87D8CC25B0C for ; Wed, 10 Aug 2022 01:33:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230102AbiHJBdX (ORCPT ); Tue, 9 Aug 2022 21:33:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57566 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230093AbiHJBdK (ORCPT ); Tue, 9 Aug 2022 21:33:10 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6B7556C111; Tue, 9 Aug 2022 18:33:09 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 08CDE6122F; Wed, 10 Aug 2022 01:33:09 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5E23AC433C1; Wed, 10 Aug 2022 01:33:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1660095188; bh=NQdbt0OH32xWjfCqJNjNQ55AmjOELt80nw6DZydmkdM=; h=Date:To:From:Subject:From; b=UAu3ujI+AWHnxZuVuQ2WE/87mvTEPqBe7/A7sEP36JyRHIrnRxyB8L4FiqL5SCIIS z9HARQnQpMCMJ92nGYvOSjUO+msGbsjcHOoUexyYjYg8wptRYRFLg7gKEa7Ifeq65P oi1ouDBGM0lLd3adNrFTAdac+7rv+qmmZbC2Od9s= Date: Tue, 09 Aug 2022 18:33:07 -0700 To: mm-commits@vger.kernel.org, stable@vger.kernel.org, john.p.donnelly@oracle.com, hch@lst.de, david@redhat.com, bhe@redhat.com, mhocko@suse.com, akpm@linux-foundation.org From: Andrew Morton Subject: + dma-pool-do-not-complain-if-dma-pool-is-not-allocated.patch added to mm-hotfixes-unstable branch Message-Id: <20220810013308.5E23AC433C1@smtp.kernel.org> Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org The patch titled Subject: Re: dma/pool: do not complain if DMA pool is not allocated has been added to the -mm mm-hotfixes-unstable branch. Its filename is dma-pool-do-not-complain-if-dma-pool-is-not-allocated.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/dma-pool-do-not-complain-if-dma-pool-is-not-allocated.patch This patch will later appear in the mm-hotfixes-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Michal Hocko Subject: Re: dma/pool: do not complain if DMA pool is not allocated Date: Tue, 9 Aug 2022 17:37:59 +0200 We have a system complaining 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. Link: https://lkml.kernel.org/r/YvJ/V2bor9Q3P6ov@dhcp22.suse.cz Signed-off-by: Michal Hocko Cc: Baoquan He Cc: Christoph Hellwig Cc: John Donnelly Cc: David Hildenbrand Cc: Signed-off-by: Andrew Morton --- kernel/dma/pool.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/kernel/dma/pool.c~dma-pool-do-not-complain-if-dma-pool-is-not-allocated +++ a/kernel/dma/pool.c @@ -205,7 +205,7 @@ static int __init dma_atomic_pool_init(v 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; } _ Patches currently in -mm which might be from mhocko@suse.com are dma-pool-do-not-complain-if-dma-pool-is-not-allocated.patch