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=-6.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no 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 68FFAC48BE0 for ; Fri, 11 Jun 2021 19:48:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5168961285 for ; Fri, 11 Jun 2021 19:48:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230511AbhFKTua (ORCPT ); Fri, 11 Jun 2021 15:50:30 -0400 Received: from mail.kernel.org ([198.145.29.99]:55512 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229530AbhFKTu1 (ORCPT ); Fri, 11 Jun 2021 15:50:27 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 5747F61285; Fri, 11 Jun 2021 19:48:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1623440908; bh=v7eYxzyytJiOKbDzrvPZp6KcvoP06S3tswJdQgsAKLc=; h=Date:From:To:Cc:Subject:From; b=PuE0pg8GBE45URnE7aXOvl/hpX+frcJDGCz+zpkPoU3ByOgjobvPRFArjL1CocuuB kRXbl2ES+CoVo1typbVdWc6nxhb7ejMGm5iWFifsHahY7lx8X3CLKbxWNYFGHDZEIN Bkt4pHoLJkxx2PbM+68q8I5qlDQ5t8z3eDJ2/2qO/VyzpMGeeN6+ojgZjUqyqzmQnL a7Rdd9prq2Tf/EnwuuhXKWe99RIJM/rLKHLVrmKOcHQbFWMBbRSU4Vargk6d6iyRQV nWjb7ACkmjTvr7zUJLzdSF92Zvpb9/1OuAyYOjvzA7GJchVmQB/eIW3Cy/wsrCfWoU z6AzrKQ47hQVw== Date: Fri, 11 Jun 2021 12:48:26 -0700 From: Nathan Chancellor To: "K. Y. Srinivasan" , Haiyang Zhang , Stephen Hemminger , Wei Liu , Dexuan Cui Cc: linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org Subject: vmemmap alloc failure in hot_add_req() Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi all, I am occasionally seeing a kernel warning when running virtual machines in Hyper-V, which usually happens a minute or so after boot. It does not happen on every boot and it is reproducible on at least v5.10. I think it might have something to do with constant reboots, which I do when testing various kernels. The stack trace is as follows: [ 49.215291] kworker/0:1: vmemmap alloc failure: order:9, mode:0x4cc0(GFP_KERNEL|__GFP_RETRY_MAYFAIL), nodemask=(null),cpuset=/,mems_allowed=0 [ 49.215299] CPU: 0 PID: 18 Comm: kworker/0:1 Not tainted 5.13.0-rc5 #1 [ 49.215301] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v4.0 11/01/2019 [ 49.215302] Workqueue: events hot_add_req [hv_balloon] [ 49.215307] Call Trace: [ 49.215310] dump_stack+0x76/0x94 [ 49.215314] warn_alloc.cold+0x78/0xdc [ 49.215316] ? __alloc_pages+0x200/0x230 [ 49.215319] vmemmap_alloc_block+0x86/0xdc [ 49.215323] vmemmap_populate+0x10e/0x31c [ 49.215324] __populate_section_memmap+0x38/0x4e [ 49.215326] sparse_add_section+0x12c/0x1cf [ 49.215329] __add_pages+0xa9/0x130 [ 49.215330] add_pages+0x12/0x60 [ 49.215333] add_memory_resource+0x180/0x300 [ 49.215335] __add_memory+0x3b/0x80 [ 49.215336] add_memory+0x2e/0x50 [ 49.215337] hot_add_req+0x3fc/0x5a0 [hv_balloon] [ 49.215340] process_one_work+0x214/0x3e0 [ 49.215342] worker_thread+0x4d/0x3d0 [ 49.215344] ? process_one_work+0x3e0/0x3e0 [ 49.215345] kthread+0x133/0x150 [ 49.215347] ? kthread_associate_blkcg+0xc0/0xc0 [ 49.215348] ret_from_fork+0x22/0x30 [ 49.215351] Mem-Info: [ 49.215352] active_anon:251 inactive_anon:140868 isolated_anon:0 active_file:47497 inactive_file:88505 isolated_file:0 unevictable:8 dirty:14 writeback:0 slab_reclaimable:12013 slab_unreclaimable:11403 mapped:131701 shmem:12671 pagetables:3140 bounce:0 free:41388 free_pcp:37 free_cma:0 [ 49.215355] Node 0 active_anon:1004kB inactive_anon:563472kB active_file:189988kB inactive_file:354020kB unevictable:32kB isolated(anon):0kB isolated(file):0kB mapped:526804kB dirty:56kB writeback:0kB shmem:50684kB shmem_thp: 0kB shmem_pmdmapped: 0kB anon_thp: 0kB writeback_tmp:0kB kernel_stack:5904kB pagetables:12560kB all_unreclaimable? no [ 49.215358] Node 0 DMA free:6496kB min:480kB low:600kB high:720kB reserved_highatomic:0KB active_anon:0kB inactive_anon:3120kB active_file:2584kB inactive_file:2792kB unevictable:0kB writepending:0kB present:15996kB managed:15360kB mlocked:0kB bounce:0kB free_pcp:0kB local_pcp:0kB free_cma:0kB [ 49.215361] lowmem_reserve[]: 0 1384 1384 1384 1384 [ 49.215364] Node 0 DMA32 free:159056kB min:44572kB low:55712kB high:66852kB reserved_highatomic:0KB active_anon:1004kB inactive_anon:560352kB active_file:187004kB inactive_file:350864kB unevictable:32kB writepending:56kB present:1555760kB managed:1432388kB mlocked:32kB bounce:0kB free_pcp:172kB local_pcp:0kB free_cma:0kB [ 49.215367] lowmem_reserve[]: 0 0 0 0 0 [ 49.215369] Node 0 DMA: 17*4kB (UM) 13*8kB (M) 10*16kB (M) 3*32kB (ME) 3*64kB (UME) 4*128kB (UME) 1*256kB (E) 2*512kB (UE) 2*1024kB (ME) 1*2048kB (E) 0*4096kB = 6508kB [ 49.215377] Node 0 DMA32: 8061*4kB (UME) 5892*8kB (UME) 2449*16kB (UME) 604*32kB (UME) 207*64kB (UME) 49*128kB (UM) 7*256kB (M) 1*512kB (M) 0*1024kB 0*2048kB 0*4096kB = 159716kB [ 49.215388] 148696 total pagecache pages [ 49.215388] 0 pages in swap cache [ 49.215389] Swap cache stats: add 0, delete 0, find 0/0 [ 49.215390] Free swap = 0kB [ 49.215390] Total swap = 0kB [ 49.215391] 392939 pages RAM [ 49.215391] 0 pages HighMem/MovableOnly [ 49.215391] 31002 pages reserved [ 49.215392] 0 pages cma reserved [ 49.215393] 0 pages hwpoisoned Is this a known issue and/or am I doing something wrong? I only noticed this because there are times when I am compiling something intensive in the VM such as LLVM and the VM runs out of memory even though I have plenty of free memory on the host but I am not sure if this warning is related to that issue. I do not have much experience with Hyper-V so it is possible I do not have something configured properly or there is some other issue going on. Let me know if there is any further information I can provide or help debug in any way. Cheers, Nathan