From patchwork Tue Jul 12 03:28:57 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Naoya Horiguchi X-Patchwork-Id: 12914505 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 51A05C433EF for ; Tue, 12 Jul 2022 03:29:41 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id E7DC7940041; Mon, 11 Jul 2022 23:29:40 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id E2EDB940033; Mon, 11 Jul 2022 23:29:40 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id CF6EB940041; Mon, 11 Jul 2022 23:29:40 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id BEB8B940033 for ; Mon, 11 Jul 2022 23:29:40 -0400 (EDT) Received: from smtpin30.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay06.hostedemail.com (Postfix) with ESMTP id 90C18334E3 for ; Tue, 12 Jul 2022 03:29:40 +0000 (UTC) X-FDA: 79677018120.30.1FFE948 Received: from out1.migadu.com (out1.migadu.com [91.121.223.63]) by imf15.hostedemail.com (Postfix) with ESMTP id 25041A0067 for ; Tue, 12 Jul 2022 03:29:40 +0000 (UTC) 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=1657596579; 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: in-reply-to:in-reply-to:references:references; bh=uqTUcL/1g55vPSy/6WoiqRY0OAXu71rE6dOMRAXFqvg=; b=ew8Sp6O1Ws+OTOljaPsEkZXh9NjZEmKMWRZabyUs0h5xFIzVYU4Vt60WB7P204h1JlpJTz UkpsoPUPe0hUcNNSrd/WSfEr8ZlZSqS6pTvD0DMTzJ1XkiK/7Tp+ceL4SdVjtWab0ZN8HV i25MTuoKG4HlX0fugjkgwvDuBF8bWaA= From: Naoya Horiguchi To: linux-mm@kvack.org Cc: Andrew Morton , David Hildenbrand , Mike Kravetz , Miaohe Lin , Liu Shixin , Yang Shi , Oscar Salvador , Muchun Song , Naoya Horiguchi , linux-kernel@vger.kernel.org Subject: [mm-unstable PATCH v6 7/8] mm, hwpoison: skip raw hwpoison page in freeing 1GB hugepage Date: Tue, 12 Jul 2022 12:28:57 +0900 Message-Id: <20220712032858.170414-8-naoya.horiguchi@linux.dev> In-Reply-To: <20220712032858.170414-1-naoya.horiguchi@linux.dev> References: <20220712032858.170414-1-naoya.horiguchi@linux.dev> MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT X-Migadu-Auth-User: linux.dev ARC-Authentication-Results: i=1; imf15.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=ew8Sp6O1; dmarc=pass (policy=none) header.from=linux.dev; spf=pass (imf15.hostedemail.com: domain of naoya.horiguchi@linux.dev designates 91.121.223.63 as permitted sender) smtp.mailfrom=naoya.horiguchi@linux.dev ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1657596580; 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:in-reply-to:references:references:dkim-signature; bh=uqTUcL/1g55vPSy/6WoiqRY0OAXu71rE6dOMRAXFqvg=; b=QQ7jWlgJV3YUTwV45QO6+EBkGioijJ92qud3l7hfTN9XC/FBy5BCdIb46778kdUqYCzCHX EM+P2XZ0if5KuCSWHfX0ce2rU0+sLag1j7b0+i+mwCcgQApQlREIUjdgeMFhvyUtaIs6AA U6bhU99PzjN4E+rBM3colTx02fRFad8= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1657596580; a=rsa-sha256; cv=none; b=S33pW71AllaH7m5ODJiWFIXXKva+t3Jzjz07XF4HjvXPH5XVhNLGO0NUK6uEE1g7dheKbd RGVxM61UpuTahVAMZGj9Os9gMMDRZrDn9Jt+64pTkTcLePYoOa8i+BR1Jtg59Cnd1S18AB 4erp8Nb6gJOhiqYznOFiKVM/4ebletI= Authentication-Results: imf15.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=ew8Sp6O1; dmarc=pass (policy=none) header.from=linux.dev; spf=pass (imf15.hostedemail.com: domain of naoya.horiguchi@linux.dev designates 91.121.223.63 as permitted sender) smtp.mailfrom=naoya.horiguchi@linux.dev X-Stat-Signature: f54w5tdzymyz81ayro5ukoi4de5jzo3u X-Rspamd-Queue-Id: 25041A0067 X-Rspam-User: X-Rspamd-Server: rspam10 X-HE-Tag: 1657596579-138596 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: From: Naoya Horiguchi Currently if memory_failure() (modified to remove blocking code with subsequent patch) is called on a page in some 1GB hugepage, memory error handling fails and the raw error page gets into leaked state. The impact is small in production systems (just leaked single 4kB page), but this limits the testability because unpoison doesn't work for it. We can no longer create 1GB hugepage on the 1GB physical address range with such leaked pages, that's not useful when testing on small systems. When a hwpoison page in a 1GB hugepage is handled, it's caught by the PageHWPoison check in free_pages_prepare() because the 1GB hugepage is broken down into raw error pages before coming to this point: if (unlikely(PageHWPoison(page)) && !order) { ... return false; } Then, the page is not sent to buddy and the page refcount is left 0. Originally this check is supposed to work when the error page is freed from page_handle_poison() (that is called from soft-offline), but now we are opening another path to call it, so the callers of __page_handle_poison() need to handle the case by considering the return value 0 as success. Then page refcount for hwpoison is properly incremented so unpoison works. Signed-off-by: Naoya Horiguchi Reviewed-by: Miaohe Lin --- v2 -> v3: - remove "res = MF_FAILED" in try_memory_failure_hugetlb (by Miaohe) --- mm/memory-failure.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 390cb7df2f4a..a8be69f81aa0 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -1084,7 +1084,6 @@ static int me_huge_page(struct page_state *ps, struct page *p) res = truncate_error_page(hpage, page_to_pfn(p), mapping); unlock_page(hpage); } else { - res = MF_FAILED; unlock_page(hpage); /* * migration entry prevents later access on error hugepage, @@ -1092,9 +1091,11 @@ static int me_huge_page(struct page_state *ps, struct page *p) * subpages. */ put_page(hpage); - if (__page_handle_poison(p) > 0) { + if (__page_handle_poison(p) >= 0) { page_ref_inc(p); res = MF_RECOVERED; + } else { + res = MF_FAILED; } } @@ -1857,10 +1858,11 @@ static int try_memory_failure_hugetlb(unsigned long pfn, int flags, int *hugetlb */ if (res == 0) { unlock_page(head); - res = MF_FAILED; - if (__page_handle_poison(p) > 0) { + if (__page_handle_poison(p) >= 0) { page_ref_inc(p); res = MF_RECOVERED; + } else { + res = MF_FAILED; } action_result(pfn, MF_MSG_FREE_HUGE, res); return res == MF_RECOVERED ? 0 : -EBUSY;