From patchwork Mon Dec 27 00:32:19 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Morton X-Patchwork-Id: 528708 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 6B072C433F5 for ; Mon, 27 Dec 2021 00:32:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234872AbhL0AcW (ORCPT ); Sun, 26 Dec 2021 19:32:22 -0500 Received: from dfw.source.kernel.org ([139.178.84.217]:57264 "EHLO dfw.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234866AbhL0AcV (ORCPT ); Sun, 26 Dec 2021 19:32:21 -0500 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 265D660F22; Mon, 27 Dec 2021 00:32:21 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 045E5C36AE8; Mon, 27 Dec 2021 00:32:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1640565140; bh=RQbsofjZR6yDmWsk2bBY9xNCUBevUhYc38UgqhuCkZE=; h=Date:From:To:Subject:From; b=geOumw+FRd/vuLw+UrH/M8kL+GGSfWxM5JyhL7EF9Yxn2ShW779wFKvD40iCMu94M sz9Ns5DYJ7SxoOheIIM+BzSvH9ve/DTNsghqWhrJLuUveqt37220qfRstJ69o7GnnO DIdvVPAltn+KoZeF1/reNQghppOQ9ddy3qjtY0hQ= Date: Sun, 26 Dec 2021 16:32:19 -0800 From: akpm@linux-foundation.org To: mm-commits@vger.kernel.org, vbabka@suse.cz, stable@vger.kernel.org, robin.murphy@arm.com, rientjes@google.com, penberg@kernel.org, m.szyprowski@samsung.com, john.p.donnelly@oracle.com, iamjoonsoo.kim@lge.com, hch@lst.de, david@redhat.com, David.Laight@ACULAB.COM, cl@linux.com, bp@alien8.de, 42.hyeyoo@gmail.com, bhe@redhat.com Subject: + dma-pool-create-dma-atomic-pool-only-if-dma-zone-has-managed-pages.patch added to -mm tree Message-ID: <20211227003219.smGaI%akpm@linux-foundation.org> User-Agent: s-nail v14.9.10 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org The patch titled Subject: dma/pool: create dma atomic pool only if dma zone has managed pages has been added to the -mm tree. Its filename is dma-pool-create-dma-atomic-pool-only-if-dma-zone-has-managed-pages.patch This patch should soon appear at https://ozlabs.org/~akpm/mmots/broken-out/dma-pool-create-dma-atomic-pool-only-if-dma-zone-has-managed-pages.patch and later at https://ozlabs.org/~akpm/mmotm/broken-out/dma-pool-create-dma-atomic-pool-only-if-dma-zone-has-managed-pages.patch 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 and is updated there every 3-4 working days ------------------------------------------------------ From: Baoquan He Subject: dma/pool: create dma atomic pool only if dma zone has managed pages Currently three dma atomic pools are initialized as long as the relevant kernel codes are built in. While in kdump kernel of x86_64, this is not right when trying to create atomic_pool_dma, because there's no managed pages in DMA zone. In the case, DMA zone only has low 1M memory presented and locked down by memblock allocator. So no pages are added into buddy of DMA zone. Please check commit f1d4d47c5851 ("x86/setup: Always reserve the first 1M of RAM"). Then in kdump kernel of x86_64, it always prints below failure message: DMA: preallocated 128 KiB GFP_KERNEL pool for atomic allocations swapper/0: page allocation failure: order:5, mode:0xcc1(GFP_KERNEL|GFP_DMA), nodemask=(null),cpuset=/,mems_allowed=0 CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.13.0-0.rc5.20210611git929d931f2b40.42.fc35.x86_64 #1 Hardware name: Dell Inc. PowerEdge R910/0P658H, BIOS 2.12.0 06/04/2018 Call Trace: dump_stack+0x7f/0xa1 warn_alloc.cold+0x72/0xd6 ? _raw_spin_unlock_irq+0x24/0x40 ? __alloc_pages_direct_compact+0x90/0x1b0 __alloc_pages_slowpath.constprop.0+0xf29/0xf50 ? __cond_resched+0x16/0x50 ? prepare_alloc_pages.constprop.0+0x19d/0x1b0 __alloc_pages+0x24d/0x2c0 ? __dma_atomic_pool_init+0x93/0x93 alloc_page_interleave+0x13/0xb0 atomic_pool_expand+0x118/0x210 ? __dma_atomic_pool_init+0x93/0x93 __dma_atomic_pool_init+0x45/0x93 dma_atomic_pool_init+0xdb/0x176 do_one_initcall+0x67/0x320 ? rcu_read_lock_sched_held+0x3f/0x80 kernel_init_freeable+0x290/0x2dc ? rest_init+0x24f/0x24f kernel_init+0xa/0x111 ret_from_fork+0x22/0x30 Mem-Info: ...... DMA: failed to allocate 128 KiB GFP_KERNEL|GFP_DMA pool for atomic allocation DMA: preallocated 128 KiB GFP_KERNEL|GFP_DMA32 pool for atomic allocations Here, let's check if DMA zone has managed pages, then create atomic_pool_dma if yes. Otherwise just skip it. Link: https://lkml.kernel.org/r/20211223094435.248523-3-bhe@redhat.com Fixes: 6f599d84231f ("x86/kdump: Always reserve the low 1M when the crashkernel option is specified") Signed-off-by: Baoquan He Reviewed-by: Christoph Hellwig Acked-by: John Donnelly Cc: Marek Szyprowski Cc: Robin Murphy Cc: Borislav Petkov Cc: Christoph Lameter Cc: David Hildenbrand Cc: David Laight Cc: David Rientjes Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com> Cc: Joonsoo Kim Cc: Pekka Enberg Cc: Vlastimil Babka Cc: Signed-off-by: Andrew Morton --- kernel/dma/pool.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/kernel/dma/pool.c~dma-pool-create-dma-atomic-pool-only-if-dma-zone-has-managed-pages +++ a/kernel/dma/pool.c @@ -203,7 +203,7 @@ static int __init dma_atomic_pool_init(v GFP_KERNEL); if (!atomic_pool_kernel) ret = -ENOMEM; - if (IS_ENABLED(CONFIG_ZONE_DMA)) { + if (has_managed_dma()) { atomic_pool_dma = __dma_atomic_pool_init(atomic_pool_size, GFP_KERNEL | GFP_DMA); if (!atomic_pool_dma) @@ -226,7 +226,7 @@ static inline struct gen_pool *dma_guess if (prev == NULL) { if (IS_ENABLED(CONFIG_ZONE_DMA32) && (gfp & GFP_DMA32)) return atomic_pool_dma32; - if (IS_ENABLED(CONFIG_ZONE_DMA) && (gfp & GFP_DMA)) + if (atomic_pool_dma && (gfp & GFP_DMA)) return atomic_pool_dma; return atomic_pool_kernel; }