From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id BB17413A3F4 for ; Thu, 13 Jun 2024 08:03:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718265783; cv=none; b=DmlW7PoPps3y/G8Uyu/ySrbRe5V+0Zb75vZfCtX65tty+g13L4UQFNExEO7wimE0KgAW2mchx+gHY/ySnLErhoZIYqFxn5ANsXLgUFLyWmb0qWigrlP/zCJd4bkZdzuDUcyQpO2KdfUf+1YMdO+xic1HY+f9MICf6Qbgxy9I5XU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718265783; c=relaxed/simple; bh=aCR0PRTg6vJf+E/Fgc7sXDtFL1l0quwGM6wS+XjmPMg=; h=Subject:To:Cc:From:Date:Message-ID:MIME-Version:Content-Type; b=AOmm0pSqe02IOhb07YXF3KGNnDsxBzBWdooWBr79C51eYititKnb6ASZimSzZ6qiRjqzTeiGdaln43pgwykb74O4gvNTRuvBSc7y91yyQuTeGrPGM86HfLCoodkcnVVP1XdK9fYMQ+KU9IMD4CSXgAxJ6rpLvgyTFN9VRTldXcQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=X+aQU9WA; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="X+aQU9WA" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 38FBEC2BBFC; Thu, 13 Jun 2024 08:03:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1718265783; bh=aCR0PRTg6vJf+E/Fgc7sXDtFL1l0quwGM6wS+XjmPMg=; h=Subject:To:Cc:From:Date:From; b=X+aQU9WAUOPbW0EFgwiobO+ihtThWU8MHmIg7bZCNGhGc0z6tkcshtPSt8nSis6ia hdO4JFlYzHH+OGBDBic5kv4mV8OIr15dLJCk9wYCdjm0bgt2Fry9HVSWc4ulFfGGG8 GUFIVwguplmjz2b2w1mZOi7UtfqLvvWLlAU6rV3s= Subject: FAILED: patch "[PATCH] mm/huge_memory: don't unpoison huge_zero_folio" failed to apply to 6.6-stable tree To: linmiaohe@huawei.com,akpm@linux-foundation.org,anshuman.khandual@arm.com,david@redhat.com,nao.horiguchi@gmail.com,osalvador@suse.de,shy828301@gmail.com,stable@vger.kernel.org,xuyu@linux.alibaba.com Cc: From: Date: Thu, 13 Jun 2024 10:02:58 +0200 Message-ID: <2024061358-duplicate-demeaning-9772@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit The patch below does not apply to the 6.6-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y git checkout FETCH_HEAD git cherry-pick -x fe6f86f4b40855a130a19aa589f9ba7f650423f4 # git commit -s git send-email --to '' --in-reply-to '2024061358-duplicate-demeaning-9772@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^.. Possible dependencies: fe6f86f4b408 ("mm/huge_memory: don't unpoison huge_zero_folio") thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From fe6f86f4b40855a130a19aa589f9ba7f650423f4 Mon Sep 17 00:00:00 2001 From: Miaohe Lin Date: Thu, 16 May 2024 20:26:08 +0800 Subject: [PATCH] mm/huge_memory: don't unpoison huge_zero_folio When I did memory failure tests recently, below panic occurs: kernel BUG at include/linux/mm.h:1135! invalid opcode: 0000 [#1] PREEMPT SMP NOPTI CPU: 9 PID: 137 Comm: kswapd1 Not tainted 6.9.0-rc4-00491-gd5ce28f156fe-dirty #14 RIP: 0010:shrink_huge_zero_page_scan+0x168/0x1a0 RSP: 0018:ffff9933c6c57bd0 EFLAGS: 00000246 RAX: 000000000000003e RBX: 0000000000000000 RCX: ffff88f61fc5c9c8 RDX: 0000000000000000 RSI: 0000000000000027 RDI: ffff88f61fc5c9c0 RBP: ffffcd7c446b0000 R08: ffffffff9a9405f0 R09: 0000000000005492 R10: 00000000000030ea R11: ffffffff9a9405f0 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: ffff88e703c4ac00 FS: 0000000000000000(0000) GS:ffff88f61fc40000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055f4da6e9878 CR3: 0000000c71048000 CR4: 00000000000006f0 Call Trace: do_shrink_slab+0x14f/0x6a0 shrink_slab+0xca/0x8c0 shrink_node+0x2d0/0x7d0 balance_pgdat+0x33a/0x720 kswapd+0x1f3/0x410 kthread+0xd5/0x100 ret_from_fork+0x2f/0x50 ret_from_fork_asm+0x1a/0x30 Modules linked in: mce_inject hwpoison_inject ---[ end trace 0000000000000000 ]--- RIP: 0010:shrink_huge_zero_page_scan+0x168/0x1a0 RSP: 0018:ffff9933c6c57bd0 EFLAGS: 00000246 RAX: 000000000000003e RBX: 0000000000000000 RCX: ffff88f61fc5c9c8 RDX: 0000000000000000 RSI: 0000000000000027 RDI: ffff88f61fc5c9c0 RBP: ffffcd7c446b0000 R08: ffffffff9a9405f0 R09: 0000000000005492 R10: 00000000000030ea R11: ffffffff9a9405f0 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: ffff88e703c4ac00 FS: 0000000000000000(0000) GS:ffff88f61fc40000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055f4da6e9878 CR3: 0000000c71048000 CR4: 00000000000006f0 The root cause is that HWPoison flag will be set for huge_zero_folio without increasing the folio refcnt. But then unpoison_memory() will decrease the folio refcnt unexpectedly as it appears like a successfully hwpoisoned folio leading to VM_BUG_ON_PAGE(page_ref_count(page) == 0) when releasing huge_zero_folio. Skip unpoisoning huge_zero_folio in unpoison_memory() to fix this issue. We're not prepared to unpoison huge_zero_folio yet. Link: https://lkml.kernel.org/r/20240516122608.22610-1-linmiaohe@huawei.com Fixes: 478d134e9506 ("mm/huge_memory: do not overkill when splitting huge_zero_page") Signed-off-by: Miaohe Lin Acked-by: David Hildenbrand Reviewed-by: Yang Shi Reviewed-by: Oscar Salvador Reviewed-by: Anshuman Khandual Cc: Naoya Horiguchi Cc: Xu Yu Cc: Signed-off-by: Andrew Morton diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 16ada4fb02b7..a9fe9eda593f 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -2546,6 +2546,13 @@ int unpoison_memory(unsigned long pfn) goto unlock_mutex; } + if (is_huge_zero_folio(folio)) { + unpoison_pr_info("Unpoison: huge zero page is not supported %#lx\n", + pfn, &unpoison_rs); + ret = -EOPNOTSUPP; + goto unlock_mutex; + } + if (!PageHWPoison(p)) { unpoison_pr_info("Unpoison: Page was already unpoisoned %#lx\n", pfn, &unpoison_rs);