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 5AB64CD5BD5 for ; Wed, 27 May 2026 14:06:56 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id BFAE16B00E2; Wed, 27 May 2026 10:06:55 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id BABA06B00E4; Wed, 27 May 2026 10:06:55 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id AE7FB6B00E5; Wed, 27 May 2026 10:06:55 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id 9F8916B00E2 for ; Wed, 27 May 2026 10:06:55 -0400 (EDT) Received: from smtpin06.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay10.hostedemail.com (Postfix) with ESMTP id 6250AC1D39 for ; Wed, 27 May 2026 14:06:55 +0000 (UTC) X-FDA: 84813375990.06.60E8B0D Received: from stravinsky.debian.org (stravinsky.debian.org [82.195.75.108]) by imf28.hostedemail.com (Postfix) with ESMTP id 977FDC0009 for ; Wed, 27 May 2026 14:06:53 +0000 (UTC) Authentication-Results: imf28.hostedemail.com; dkim=pass header.d=debian.org header.s=smtpauto.stravinsky header.b=hXRQFsrh; spf=pass (imf28.hostedemail.com: domain of leitao@debian.org designates 82.195.75.108 as permitted sender) smtp.mailfrom=leitao@debian.org; dmarc=pass (policy=none) header.from=debian.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1779890813; 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-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=WbBaNvEUUV9dHKCwKIk01dAys3/khbUwIgj2MiKwh1k=; b=Z6Pwe9ExuXxgeE5Lx/tH6xbDkgI0ddlFpHfgk2MxVlkLfU0w17YE11vV44XmQ5fMuA/gaL IhVsy1Gy3vGkSmUR73Z4rXtIHMTeqDGR/qg3qzG56SbyGwKlw5PghlFHtabaZGuJpPzJFT XC+EhkJj/pjt8oSxhsqdM9oALnNGRLA= ARC-Authentication-Results: i=1; imf28.hostedemail.com; dkim=pass header.d=debian.org header.s=smtpauto.stravinsky header.b=hXRQFsrh; spf=pass (imf28.hostedemail.com: domain of leitao@debian.org designates 82.195.75.108 as permitted sender) smtp.mailfrom=leitao@debian.org; dmarc=pass (policy=none) header.from=debian.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1779890813; a=rsa-sha256; cv=none; b=lbkL/qYTWHXwD2Gs56lfqmtTW8CX+oEaiTGtGLCjoxw5j6Yvf9mSnIWmilCJIlqIox4qs/ oiqWzOzE5/XMoQYZh4l1p+kyRk5PLmTpFKyAZoXAbBNY/wifBRdE77kBQWbZT6kEhuLTeb AXuQ4kw4ZfEJLhB0zO+BeMXEGmQRe4E= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=debian.org; s=smtpauto.stravinsky; h=X-Debian-User:Cc:To:In-Reply-To:References: Message-Id:Content-Transfer-Encoding:Content-Type:MIME-Version:Subject:Date: From:Reply-To:Content-ID:Content-Description; bh=WbBaNvEUUV9dHKCwKIk01dAys3/khbUwIgj2MiKwh1k=; b=hXRQFsrhwcO5fbPxJdZLKmAlDC /5/Oj8hsdMcdix8mPdYre37lAs2/a0dazRsm78qecUsDQOp5/BlWTs7tgauiYVwHtQJxOrqhIHS3x VO5hpMsU9x5mEztCsAvkbxvTs0dJq9GXGctAJgshsRmneMVyolxiNWlwDkJ5h1uwS38n6b9v8EpBX mo2oPfoVqD7vv2eF3CVmTGMOiz4UJbv/Pzf1iuEHyZSdoqQQpevj2E7w/UY8w9OBcfd5/wEySNfoh i0LCFKR84uFanS5/q6355tzBS2KZpjzexCmeZ3aanuRFV3bRuGjHliUIrJ+CiXKBHe8qAowY90Fg/ lmpRPmDA==; Received: from authenticated-user by stravinsky.debian.org with esmtpsa (TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.96) (envelope-from ) id 1wSEuG-003DTX-1N; Wed, 27 May 2026 14:06:48 +0000 From: Breno Leitao Date: Wed, 27 May 2026 07:06:17 -0700 Subject: [PATCH v8 4/6] mm/memory-failure: add panic option for unrecoverable pages MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260527-ecc_panic-v8-4-9ea0cfa16bb0@debian.org> References: <20260527-ecc_panic-v8-0-9ea0cfa16bb0@debian.org> In-Reply-To: <20260527-ecc_panic-v8-0-9ea0cfa16bb0@debian.org> To: Miaohe Lin , Andrew Morton , David Hildenbrand , Lorenzo Stoakes , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Shuah Khan , Naoya Horiguchi , Steven Rostedt , Masami Hiramatsu , Mathieu Desnoyers , Jonathan Corbet , Shuah Khan , "Liam R. Howlett" , "Liam R. Howlett" Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.org, Breno Leitao , linux-trace-kernel@vger.kernel.org, kernel-team@meta.com X-Mailer: b4 0.16-dev-d5d98 X-Developer-Signature: v=1; a=openpgp-sha256; l=3147; i=leitao@debian.org; h=from:subject:message-id; bh=PVkQrhhrYvBQD3vyC0lD7FiGrFyJsu0JdQyRsKIR+Qo=; b=owEBbQKS/ZANAwAIATWjk5/8eHdtAcsmYgBqFvpbj7PVLzJ01FRE86nH7X9QE2rSaA3qgOH24 VsAWQc/ZMOJAjMEAAEIAB0WIQSshTmm6PRnAspKQ5s1o5Of/Hh3bQUCahb6WwAKCRA1o5Of/Hh3 bXTiEACNvfxka9cCMrQpEcA5UqXBXxS+3NZK9HFqC8QaHpUFJgFpFNNUIv95wyLEnaUW3Iw+ZBC 19iDONTUFs6ehBZYcThrTuVs9ww0ppdn8HF5f/a61eH+h61cHAzaWPkGDa6Uexo8aiuWhIfwy1I hs2DuBJMR1AQBm8nqhHlEvj7DBPAphdbdRvtWW3kYubEdNLPYZ6TFDafxZoV494fSZQcQlPCMRm cbTlyAL6OAysiMbSv9h0WCPUGmbF52hmFC8TFBSqqWGMBstelFYKz/glnOurkDpbLdIICoCtQnJ kBApBpKqWeyPupsONN6gwGp7In1ZBE9oNyggtC2tISbY4vEm1+/xlvUjpO4l43/OV8xoPZOfsxm gVF34Vb7oKz+pFqkvmkKQ3cdVeRC7Tb4Ump+VYQN9KrfwrvQ+Cp5JdeIThG+PVkaokGUL9Z19T+ SA9Yl4871nAjgcczbO6hH/RQjFWQPmUt39WcevAc1Z1jXuMByn5/GCeXmND1BUq/K2/g1WElrvH sUu9teM90CtooOmatjcSN1YB0LVEfXGCURuOCjnzaCvhVupgFkFQWY7/haAy5Y5po2TR5mCptd4 y0RpDvWdqPsz8Zdt5Ae6sygozIgLRGXR5NOWPE3UY12AT1Qce9YF4hNfAnakE/oTIfHDriu3vHq ZzTj3JTFtMHLAUg== X-Developer-Key: i=leitao@debian.org; a=openpgp; fpr=AC8539A6E8F46702CA4A439B35A3939FFC78776D X-Debian-User: leitao X-Rspam-User: X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 977FDC0009 X-Stat-Signature: 9y8wsyq41ot35ppxj6w9f5z5gowxsckp X-HE-Tag: 1779890813-825798 X-HE-Meta: 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 CmCuiAy0 cAI9o2lvOd0aj/NRadBgC/c3jKbgbEft9q/Ox8kHc1gppIbDZ/nXLXme03sb/sTL1RIinnH/QgcmDdoLv28IPZPQUv9aC9E4M9Z4lh7MAajsUJe+AbfU7Nt6mMJyfZxJlEjrizCtCpHSR1rqpLUx7JL1NE5uDQ4fjFy+D1cPtZdHlMnCg6WsSkEJxjVBSZa+EJpsO4pB6z9y/O2wj4G2IXE1fmYjDpudFaAO+MHUy1E07NXOZqrBotGtLom6pQ3LDFasfg9/pV9muSezAvx03oJMVXnGMaTNEUddkfY7I9bjxaRAeKOhWK6OdqAk3NoQpfVX0NZwxkMJAR8x52YpTe3YIQvKeBIVmYmAo Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: Add a sysctl panic_on_unrecoverable_memory_failure (disabled by default) that triggers a kernel panic when memory_failure() encounters pages that cannot be recovered. This provides a clean crash with useful debug information rather than allowing silent data corruption or a delayed crash at an unrelated code path. Panic eligibility is intentionally narrow: only MF_MSG_KERNEL with result == MF_IGNORED panics. After the previous patch, MF_MSG_KERNEL covers PG_reserved pages and the kernel-owned pages promoted from get_hwpoison_page() via -ENOTRECOVERABLE (slab, page tables, large-kmalloc). All other action types are excluded: - MF_MSG_GET_HWPOISON and MF_MSG_KERNEL_HIGH_ORDER can be reached by transient refcount races with the page allocator (an in-flight buddy allocation has refcount 0 and is no longer on the buddy free list, briefly), and panicking on them would risk killing the box for what is actually a recoverable userspace page. - MF_MSG_UNKNOWN means identify_page_state() could not classify the page; that is precisely the wrong basis for a panic decision. Signed-off-by: Breno Leitao --- mm/memory-failure.c | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 14c0a958638c..dcd53dbc6aec 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -74,6 +74,8 @@ static int sysctl_memory_failure_recovery __read_mostly = 1; static int sysctl_enable_soft_offline __read_mostly = 1; +static int sysctl_panic_on_unrecoverable_mf __read_mostly; + atomic_long_t num_poisoned_pages __read_mostly = ATOMIC_LONG_INIT(0); static bool hw_memory_failure __read_mostly = false; @@ -155,6 +157,15 @@ static const struct ctl_table memory_failure_table[] = { .proc_handler = proc_dointvec_minmax, .extra1 = SYSCTL_ZERO, .extra2 = SYSCTL_ONE, + }, + { + .procname = "panic_on_unrecoverable_memory_failure", + .data = &sysctl_panic_on_unrecoverable_mf, + .maxlen = sizeof(sysctl_panic_on_unrecoverable_mf), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = SYSCTL_ZERO, + .extra2 = SYSCTL_ONE, } }; @@ -1255,6 +1266,15 @@ static void update_per_node_mf_stats(unsigned long pfn, ++mf_stats->total; } +static bool panic_on_unrecoverable_mf(enum mf_action_page_type type, + enum mf_result result) +{ + if (!sysctl_panic_on_unrecoverable_mf || result != MF_IGNORED) + return false; + + return type == MF_MSG_KERNEL; +} + /* * "Dirty/Clean" indication is not 100% accurate due to the possibility of * setting PG_dirty outside page lock. See also comment above set_page_dirty(). @@ -1272,6 +1292,9 @@ static int action_result(unsigned long pfn, enum mf_action_page_type type, pr_err("%#lx: recovery action for %s: %s\n", pfn, action_page_types[type], action_name[result]); + if (panic_on_unrecoverable_mf(type, result)) + panic("Memory failure: %#lx: unrecoverable page", pfn); + return (result == MF_RECOVERED || result == MF_DELAYED) ? 0 : -EBUSY; } -- 2.54.0