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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id EA174C433F5 for ; Tue, 12 Apr 2022 08:59:25 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 75CBF6B007B; Tue, 12 Apr 2022 04:59:25 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 6E61E6B007D; Tue, 12 Apr 2022 04:59:25 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 5ADB96B007E; Tue, 12 Apr 2022 04:59:25 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (relay.a.hostedemail.com [64.99.140.24]) by kanga.kvack.org (Postfix) with ESMTP id 4B56A6B007B for ; Tue, 12 Apr 2022 04:59:25 -0400 (EDT) Received: from smtpin06.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay08.hostedemail.com (Postfix) with ESMTP id 1F9A221FEA for ; Tue, 12 Apr 2022 08:59:25 +0000 (UTC) X-FDA: 79347628290.06.4E7EE97 Received: from out30-133.freemail.mail.aliyun.com (out30-133.freemail.mail.aliyun.com [115.124.30.133]) by imf22.hostedemail.com (Postfix) with ESMTP id 2FE52C000B for ; Tue, 12 Apr 2022 08:59:22 +0000 (UTC) X-Alimail-AntiSpam:AC=PASS;BC=-1|-1;BR=01201311R321e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04395;MF=xuyu@linux.alibaba.com;NM=1;PH=DS;RN=4;SR=0;TI=SMTPD_---0V9uAJ7T_1649753955; Received: from 30.225.28.172(mailfrom:xuyu@linux.alibaba.com fp:SMTPD_---0V9uAJ7T_1649753955) by smtp.aliyun-inc.com(127.0.0.1); Tue, 12 Apr 2022 16:59:16 +0800 Message-ID: <4970f9f5-0f82-c173-b101-bdb8c9fabd9c@linux.alibaba.com> Date: Tue, 12 Apr 2022 16:59:15 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:91.0) Gecko/20100101 Thunderbird/91.8.0 Subject: Re: [PATCH] mm/memory-failure.c: bail out early if huge zero page Content-Language: en-US From: Yu Xu To: linux-mm@kvack.org Cc: akpm@linux-foundation.org, linmiaohe@huawei.com, osalvador@suse.de References: <49273e6688d7571756603dac996692a15f245d58.1649603963.git.xuyu@linux.alibaba.com> In-Reply-To: <49273e6688d7571756603dac996692a15f245d58.1649603963.git.xuyu@linux.alibaba.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspam-User: Authentication-Results: imf22.hostedemail.com; dkim=none; spf=pass (imf22.hostedemail.com: domain of xuyu@linux.alibaba.com designates 115.124.30.133 as permitted sender) smtp.mailfrom=xuyu@linux.alibaba.com; dmarc=pass (policy=none) header.from=alibaba.com X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 2FE52C000B X-Stat-Signature: qr8fynimzj65xg1zrnq8mgdpobxyjxyh X-HE-Tag: 1649753962-963651 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Hi, Miaohe and Oscar, Thanks for your kind suggestions! Will send v2 after amend and test. On 4/10/22 11:22 PM, Xu Yu wrote: > Kernel panic when injecting memory_failure for the global huge_zero_page, > when CONFIG_DEBUG_VM is enabled, as follows. > > [ 5.582720] Injecting memory failure for pfn 0x109ff9 at process virtual address 0x20ff9000 > [ 5.583786] page:00000000fb053fc3 refcount:2 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x109e00 > [ 5.584900] head:00000000fb053fc3 order:9 compound_mapcount:0 compound_pincount:0 > [ 5.585796] flags: 0x17fffc000010001(locked|head|node=0|zone=2|lastcpupid=0x1ffff) > [ 5.586712] raw: 017fffc000010001 0000000000000000 dead000000000122 0000000000000000 > [ 5.587640] raw: 0000000000000000 0000000000000000 00000002ffffffff 0000000000000000 > [ 5.588565] page dumped because: VM_BUG_ON_PAGE(is_huge_zero_page(head)) > [ 5.589398] ------------[ cut here ]------------ > [ 5.589952] kernel BUG at mm/huge_memory.c:2499! > [ 5.590516] invalid opcode: 0000 [#1] PREEMPT SMP PTI > [ 5.591120] CPU: 6 PID: 553 Comm: split_bug Not tainted 5.18.0-rc1+ #11 > [ 5.591904] Hardware name: Alibaba Cloud Alibaba Cloud ECS, BIOS 3288b3c 04/01/2014 > [ 5.592817] RIP: 0010:split_huge_page_to_list+0x66a/0x880 > [ 5.593469] Code: 84 9b fb ff ff 48 8b 7c 24 08 31 f6 e8 9f 5d 2a 00 b8 b8 02 00 00 e9 e8 fb ff ff 48 c7 c6 e8 47 3c 82 4c b > [ 5.595806] RSP: 0018:ffffc90000dcbdf8 EFLAGS: 00010246 > [ 5.596434] RAX: 000000000000003c RBX: 0000000000000001 RCX: 0000000000000000 > [ 5.597322] RDX: 0000000000000000 RSI: ffffffff823e4c4f RDI: 00000000ffffffff > [ 5.598162] RBP: ffff88843fffdb40 R08: 0000000000000000 R09: 00000000fffeffff > [ 5.598999] R10: ffffc90000dcbc48 R11: ffffffff82d68448 R12: ffffea0004278000 > [ 5.599849] R13: ffffffff823c6203 R14: 0000000000109ff9 R15: ffffea000427fe40 > [ 5.600693] FS: 00007fc375a26740(0000) GS:ffff88842fd80000(0000) knlGS:0000000000000000 > [ 5.601640] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > [ 5.602304] CR2: 00007fc3757c9290 CR3: 0000000102174006 CR4: 00000000003706e0 > [ 5.603139] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > [ 5.603977] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > [ 5.604806] Call Trace: > [ 5.605101] > [ 5.605357] ? __irq_work_queue_local+0x39/0x70 > [ 5.605904] try_to_split_thp_page+0x3a/0x130 > [ 5.606430] memory_failure+0x128/0x800 > [ 5.606888] madvise_inject_error.cold+0x8b/0xa1 > [ 5.607444] __x64_sys_madvise+0x54/0x60 > [ 5.607915] do_syscall_64+0x35/0x80 > [ 5.608347] entry_SYSCALL_64_after_hwframe+0x44/0xae > [ 5.608949] RIP: 0033:0x7fc3754f8bf9 > [ 5.609374] Code: 01 00 48 81 c4 80 00 00 00 e9 f1 fe ff ff 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 8 > [ 5.611554] RSP: 002b:00007ffeda93a1d8 EFLAGS: 00000217 ORIG_RAX: 000000000000001c > [ 5.612441] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fc3754f8bf9 > [ 5.613269] RDX: 0000000000000064 RSI: 0000000000003000 RDI: 0000000020ff9000 > [ 5.614108] RBP: 00007ffeda93a200 R08: 0000000000000000 R09: 0000000000000000 > [ 5.614946] R10: 00000000ffffffff R11: 0000000000000217 R12: 0000000000400490 > [ 5.615787] R13: 00007ffeda93a2e0 R14: 0000000000000000 R15: 0000000000000000 > [ 5.616626] > > In fact, huge_zero_page is unhandlable currently in either soft offline > or memory failure injection. With CONFIG_DEBUG_VM disabled, > huge_zero_page is bailed out when checking HWPoisonHandlable() in > get_any_page(), or checking page mapping in split_huge_page_to_list(). > > This makes huge_zero_page bail out early in madvise_inject_error(), and > panic above won't happen again. > > Reported-by: Abaci > Signed-off-by: Xu Yu > --- > mm/madvise.c | 13 +++++++++++-- > 1 file changed, 11 insertions(+), 2 deletions(-) > > diff --git a/mm/madvise.c b/mm/madvise.c > index 1873616a37d2..03ad50d222e0 100644 > --- a/mm/madvise.c > +++ b/mm/madvise.c > @@ -1079,7 +1079,7 @@ static int madvise_inject_error(int behavior, > > for (; start < end; start += size) { > unsigned long pfn; > - struct page *page; > + struct page *page, *head; > int ret; > > ret = get_user_pages_fast(start, 1, 0, &page); > @@ -1087,12 +1087,21 @@ static int madvise_inject_error(int behavior, > return ret; > pfn = page_to_pfn(page); > > + head = compound_head(page); > + if (unlikely(is_huge_zero_page(head))) { > + pr_warn("Unhandlable attempt to %s pfn %#lx at process virtual address %#lx\n", > + behavior == MADV_SOFT_OFFLINE ? "soft offline" : > + "inject memory failure for", > + pfn, start); > + return -EINVAL; > + } > + > /* > * When soft offlining hugepages, after migrating the page > * we dissolve it, therefore in the second loop "page" will > * no longer be a compound page. > */ > - size = page_size(compound_head(page)); > + size = page_size(head); > > if (behavior == MADV_SOFT_OFFLINE) { > pr_info("Soft offlining pfn %#lx at process virtual address %#lx\n", -- Thanks, Yu