From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-2948269-1517591208-2-2290683215563381780 X-Sieve: CMU Sieve 3.0 X-Spam-known-sender: no X-Spam-score: 0.0 X-Spam-hits: BAYES_00 -1.9, HEADER_FROM_DIFFERENT_DOMAINS 0.001, ME_NOAUTH 0.01, RCVD_IN_DNSWL_HI -5, T_RP_MATCHES_RCVD -0.01, LANGUAGES enda, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='209.132.180.67', Host='vger.kernel.org', Country='US', FromHeader='org', MailFrom='org' X-Spam-charsets: plain='UTF-8' X-Resolved-to: greg@kroah.com X-Delivered-to: greg@kroah.com X-Mail-from: stable-owner@vger.kernel.org ARC-Seal: i=1; a=rsa-sha256; cv=none; d=messagingengine.com; s=arctest; t=1517591206; b=UliZ3XqiNRZKjDWCIudWAQ729kLrLzVdhmWyCPIf0VVgI0K uKGN1PvVTJpgpL4Xn/XsWh6UH8fnzSVkm9RkqWvOWPwDbVYw71XMs2zRhIl6H3wV qKHdIG27Vq5YzsjLMhxOlqv5NQtPLh3CXvHblx2Gxf8kV+k7zAfQ0jzzTwirbjqy e31jsRxr0u0i/wm2EeFFmATv+KX3DrLNvrqMwhkBtAMpyR8Nm+XZNmsmquHgjBXZ +US4QvI2D4qVauwzzYAaw2yAdQNCXGkPTSAyH0HbEzwCxYlxhkUXzlfKVP9IwKAk EzR+h22xDFtwbMq7nlCjC3t2G7KbmnrD3nKitjg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=from:to:cc:subject:date:message-id :in-reply-to:references:mime-version:content-type:sender :list-id; s=arctest; t=1517591206; bh=+bFW8EzfSIj232G6PVWOD0Rb90 8KOvEV3qGOGwCvwIA=; b=DG4QG/KvIZ9PK9c995tNKAUBJvpzwSStjTzoyeuLWh UVe2WtDaDeY4hKOV8Fkl3iunOvR+75nQUpS41LrhWo4VdjdugV1+W2ZCHSbBNvyh bYrw9O/4CV4EJYS5CA4jyHOQ8C/cOYyHU7vDLd2SzX8UOD50/U+zot1+7axdLhzU 6FMJRK/nUsAuR3OD4P6JmaMUPu2kpCZ5aNkdgyhJsYMFQdKDBqxvAOhKKzBxCcq0 xWG5oKse5x2Q4TTa8+dLlSAGrRPxVRafHllgl5MEfAL6/YKsEcfS6onkJ4ExVxmG mj0EGIg3/v2CKUSXmLfF8zgWHdyMqCEtiFzzuEImtk7w== ARC-Authentication-Results: i=1; mx1.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=linuxfoundation.org; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=linuxfoundation.org header.result=pass header_is_org_domain=yes Authentication-Results: mx1.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=linuxfoundation.org; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=linuxfoundation.org header.result=pass header_is_org_domain=yes Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753114AbeBBRGn (ORCPT ); Fri, 2 Feb 2018 12:06:43 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:36842 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753112AbeBBRGl (ORCPT ); Fri, 2 Feb 2018 12:06:41 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Yisheng Xie , Catalin Marinas , Michal Hocko , Andrew Morton , Linus Torvalds , Sasha Levin Subject: [PATCH 4.9 53/86] kmemleak: add scheduling point to kmemleak_scan() Date: Fri, 2 Feb 2018 17:58:13 +0100 Message-Id: <20180202140827.143784257@linuxfoundation.org> X-Mailer: git-send-email 2.16.1 In-Reply-To: <20180202140822.679101338@linuxfoundation.org> References: <20180202140822.679101338@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org X-Mailing-List: stable@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Yisheng Xie [ Upstream commit bde5f6bc68db51128f875a756e9082a6c6ff7b4c ] kmemleak_scan() will scan struct page for each node and it can be really large and resulting in a soft lockup. We have seen a soft lockup when do scan while compile kernel: watchdog: BUG: soft lockup - CPU#53 stuck for 22s! [bash:10287] [...] Call Trace: kmemleak_scan+0x21a/0x4c0 kmemleak_write+0x312/0x350 full_proxy_write+0x5a/0xa0 __vfs_write+0x33/0x150 vfs_write+0xad/0x1a0 SyS_write+0x52/0xc0 do_syscall_64+0x61/0x1a0 entry_SYSCALL64_slow_path+0x25/0x25 Fix this by adding cond_resched every MAX_SCAN_SIZE. Link: http://lkml.kernel.org/r/1511439788-20099-1-git-send-email-xieyisheng1@huawei.com Signed-off-by: Yisheng Xie Suggested-by: Catalin Marinas Acked-by: Catalin Marinas Cc: Michal Hocko Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- mm/kmemleak.c | 2 ++ 1 file changed, 2 insertions(+) --- a/mm/kmemleak.c +++ b/mm/kmemleak.c @@ -1442,6 +1442,8 @@ static void kmemleak_scan(void) if (page_count(page) == 0) continue; scan_block(page, page + 1, NULL); + if (!(pfn % (MAX_SCAN_SIZE / sizeof(*page)))) + cond_resched(); } } put_online_mems();