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]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 482C2CD4F25 for ; Thu, 14 May 2026 08:58:41 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id A06D66B008A; Thu, 14 May 2026 04:58:40 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 9B7216B008C; Thu, 14 May 2026 04:58:40 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 8CC866B0092; Thu, 14 May 2026 04:58:40 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) by kanga.kvack.org (Postfix) with ESMTP id 7A7356B008A for ; Thu, 14 May 2026 04:58:40 -0400 (EDT) Received: from smtpin17.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay07.hostedemail.com (Postfix) with ESMTP id 1C5991608D0 for ; Thu, 14 May 2026 08:58:40 +0000 (UTC) X-FDA: 84765424800.17.CBD2485 Received: from out-173.mta0.migadu.com (out-173.mta0.migadu.com [91.218.175.173]) by imf04.hostedemail.com (Postfix) with ESMTP id 447C240010 for ; Thu, 14 May 2026 08:58:38 +0000 (UTC) Authentication-Results: imf04.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=nVIpRwXF; spf=pass (imf04.hostedemail.com: domain of kaitao.cheng@linux.dev designates 91.218.175.173 as permitted sender) smtp.mailfrom=kaitao.cheng@linux.dev; dmarc=pass (policy=none) header.from=linux.dev ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1778749118; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-transfer-encoding:content-transfer-encoding: in-reply-to:references:dkim-signature; bh=71daxRLec4jyhYBAvxsKNAYEmlfTLs3LqROItb0Etew=; b=LwEAeS0RzCYo93GZN6YJlKmgErncM0O5jJ+LKWNesjN/55lFWEh9lvO+Gg/7tarAtlKsnE MA1eHyuJUniviVeNDb0M6oJU6w2YhExt6nBhrLRtHtqDXweJ2m428hFEBrnBz0Cnq2bP7H MKYxpK0Jyc5OyomHxRrfXiIO1Qx9Pv0= ARC-Authentication-Results: i=1; imf04.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=nVIpRwXF; spf=pass (imf04.hostedemail.com: domain of kaitao.cheng@linux.dev designates 91.218.175.173 as permitted sender) smtp.mailfrom=kaitao.cheng@linux.dev; dmarc=pass (policy=none) header.from=linux.dev ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1778749118; a=rsa-sha256; cv=none; b=JnPS/6/JhWiGVz3KYJ/ZnDnhI1pOVwjdGrJpTdx5u511h+UT+DIZFUftqmKGb47K6GKijH INmSbJo+zzLpacfJ6OSFE1ueU1nnxDbt/j0jYwYcjCsjWgF1SmwW3uwOsHZfHfC7EZYORT NM8FcjLLFDlg/XJv8iA0hq+N6rElMOY= X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1778749116; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=71daxRLec4jyhYBAvxsKNAYEmlfTLs3LqROItb0Etew=; b=nVIpRwXF2bayTanxg/F32tyPngv3o1/mCGuBtHPUjfYatIIn2szaOvrl6AIaOy5TwH7J6G Qy2ISDfGZAx8nIZBtScls34NVnaSb83jFva/oyZMPo01TV24mGOZNP6PyM0R0Hzn61K+G7 bnUuyYdzVrzkZS2tUP462of/uGAAdbg= From: Kaitao Cheng To: linmiaohe@huawei.com, nao.horiguchi@gmail.com, akpm@linux-foundation.org Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Kaitao Cheng Subject: [PATCH] mm/memory-failure: Use zone_pcp_disable() for poison handling Date: Thu, 14 May 2026 16:57:54 +0800 Message-ID: <20260514085754.84097-1-kaitao.cheng@linux.dev> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT X-Rspam-User: X-Rspamd-Queue-Id: 447C240010 X-Rspamd-Server: rspam06 X-Stat-Signature: jrk4hjnmfw5izntyadmbup9m3f4gdkf6 X-HE-Tag: 1778749118-941937 X-HE-Meta: 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 KLmiGN13 4A2Cy4tkCD44OlxC86cmV0zBm+nnT7FjueW/xSEmrrtUrVI3LiPJ9COrdibyvyQoBSt9k9tyMLeWSGkgTsLBMYReHXGzL0Yr6O5VSMBfE+Q5NRvKymA53PJ3Jo/9t/12KUta+yxSAqg7nx3DpveyF5JFVvaVBfIZRqkiSdjXuIqnVMQE5IGt0xtPneyuiq/QbvxqWAT7qXiwOWc7OFhJ0QXjGrp3ZWHV2vSR412z/E3KnhXnrgnHORNtqa9DJcnx5huDOzw+z8qe47aeE4h1QzwRo9czBuZdWwXwSj2D9PYFD8Y2S+K8oh3kdww== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: From: Kaitao Cheng __page_handle_poison() used drain_all_pages() instead of zone_pcp_disable() because dissolve_free_hugetlb_folio() could restore HVO vmemmap pages and decrement hugetlb_optimize_vmemmap_key. That static key update took cpu_hotplug_lock through static_key_slow_dec(), while zone_pcp_disable() holds pcp_batch_high_lock. CPU hotplug takes the locks in the opposite order through page_alloc_cpu_online/dead(), so the combination could deadlock. That dependency no longer exists. Commit da3e2d1ca43d ("mm/hugetlb: remove hugetlb_optimize_vmemmap_key static key") removed the HVO static key and the static_branch_dec() from hugetlb_vmemmap_restore_folio(). The dissolve_free_hugetlb_folio() path no longer reaches static_key_slow_dec(). Use zone_pcp_disable() again while dissolving the hugetlb folio and taking the target page off the buddy allocator. This prevents the drained PCP lists from being refilled before take_page_off_buddy() runs, making the page isolation deterministic. Signed-off-by: Kaitao Cheng --- mm/memory-failure.c | 18 +++--------------- 1 file changed, 3 insertions(+), 15 deletions(-) diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 866c4428ac7e..b9619d43173b 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -172,23 +172,11 @@ static int __page_handle_poison(struct page *page) { int ret; - /* - * zone_pcp_disable() can't be used here. It will - * hold pcp_batch_high_lock and dissolve_free_hugetlb_folio() might hold - * cpu_hotplug_lock via static_key_slow_dec() when hugetlb vmemmap - * optimization is enabled. This will break current lock dependency - * chain and leads to deadlock. - * Disabling pcp before dissolving the page was a deterministic - * approach because we made sure that those pages cannot end up in any - * PCP list. Draining PCP lists expels those pages to the buddy system, - * but nothing guarantees that those pages do not get back to a PCP - * queue if we need to refill those. - */ + zone_pcp_disable(page_zone(page)); ret = dissolve_free_hugetlb_folio(page_folio(page)); - if (!ret) { - drain_all_pages(page_zone(page)); + if (!ret) ret = take_page_off_buddy(page); - } + zone_pcp_enable(page_zone(page)); return ret; } -- 2.50.1 (Apple Git-155)