From patchwork Mon Aug 4 10:33:16 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chun-Yi Lee X-Patchwork-Id: 4669431 Return-Path: X-Original-To: patchwork-linux-pm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id A77FAC0338 for ; Mon, 4 Aug 2014 10:34:35 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id BB722200E6 for ; Mon, 4 Aug 2014 10:34:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4A242201CD for ; Mon, 4 Aug 2014 10:34:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752357AbaHDKeN (ORCPT ); Mon, 4 Aug 2014 06:34:13 -0400 Received: from mail-pa0-f49.google.com ([209.85.220.49]:49750 "EHLO mail-pa0-f49.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752349AbaHDKeK (ORCPT ); Mon, 4 Aug 2014 06:34:10 -0400 Received: by mail-pa0-f49.google.com with SMTP id hz1so9771829pad.22 for ; Mon, 04 Aug 2014 03:34:09 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=from:to:cc:subject:date:message-id; bh=i8N18b2d8XZIFe9jG7koTOkXpZmNkct3I1zRHxn5KAg=; b=tGxfOfkb9SdxDIE7N3IojDlQqeTokmg/UNrFdxlW9ugHZ1ZaGOV8oXaMCzDgnBf9/Q JOlwk3DutsGr4fBoLYrMUQIGmgyM/lRcxEXhi4WiToU6ypEdIIFWP4UB0wOeWphMqwf9 Lrz3DKNaJF6NkimdMGEr5mXjQcDqSgxxtkrkdn/PKPHvEjePEYb9gxeD5r8As4PVGtRc tEZsYl0gqcuYOwXaL9GhuW9X/NHOVGFIbqq4nlZSJXTiRnSCdqaoXlzFoMRSky7ceX1U 3va+j2v1a7aktu0ZNfKAG73YTr03kWZOeLi7h4etPvh1tWpnjIkuvxIWtWBDoi8osJwC +0Ug== X-Received: by 10.67.1.195 with SMTP id bi3mr23023528pad.74.1407148449840; Mon, 04 Aug 2014 03:34:09 -0700 (PDT) Received: from linux-rxt1.site ([130.57.30.250]) by mx.google.com with ESMTPSA id b9sm26112044pdo.3.2014.08.04.03.34.06 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 04 Aug 2014 03:34:09 -0700 (PDT) From: "Lee, Chun-Yi" X-Google-Original-From: "Lee, Chun-Yi" To: "Rafael J. Wysocki" , Len Brown , Pavel Machek Cc: linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, "Lee, Chun-Yi" Subject: [PATCH] Hibernate: check unsafe page should not in e820 reserved region Date: Mon, 4 Aug 2014 18:33:16 +0800 Message-Id: <1407148396-21405-1-git-send-email-jlee@suse.com> X-Mailer: git-send-email 1.8.4.5 Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org X-Spam-Status: No, score=-7.5 required=5.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED, DKIM_SIGNED, FREEMAIL_FROM, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, T_DKIM_INVALID, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP When the machine doesn't well handle the e820 persistent when hibernate resuming, then it may causes page fault when writing image to snapshot buffer: [ 17.929495] BUG: unable to handle kernel paging request at ffff880069d4f000 [ 17.933469] IP: [] load_image_lzo+0x810/0xe40 [ 17.933469] PGD 2194067 PUD 77ffff067 PMD 2197067 PTE 0 [ 17.933469] Oops: 0002 [#1] SMP ... The ffff880069d4f000 page is in e820 reserved region of resume boot kernel: [ 0.000000] BIOS-e820: [mem 0x0000000069d4f000-0x0000000069e12fff] reserved ... [ 0.000000] PM: Registered nosave memory: [mem 0x69d4f000-0x69e12fff] So snapshot.c mark the pfn to forbidden pages map. But, this page is also in the memory bitmap in snapshot image because it's an original page used by image kernel, so it will also mark as an unsafe(free) page in prepare_image(). That means the page in e820 when resuming mark as "forbidden" and "free", it causes get_buffer() treat it as an allocated unsafe page. Then snapshot_write_next() return this page to load_image, load_image writing content to this address, but this page didn't really allocated . So, we got page fault. Although the root cause is from BIOS, I think aggressive check and significant message in kernel will better then a page fault for issue tracking, especially when serial console unavailable. This patch adds code in mark_unsafe_pages() for check does free pages in nosave region. If so, then it print message and return fault to stop whole S4 resume process: [ 8.166004] PM: Image loading progress: 0% [ 8.658717] PM: 0x6796c000 in e820 nosave regsion: [mem 0x6796c000-0x6796cfff] [ 8.918737] PM: Read 2511940 kbytes in 1.04 seconds (2415.32 MB/s) [ 8.926633] PM: Error -14 resuming [ 8.933534] PM: Failed to load hibernation image, recovering. Cc: "Rafael J. Wysocki" Cc: Len Brown Cc: Pavel Machek Signed-off-by: Lee, Chun-Yi Acked-by: Pavel Machek --- kernel/power/snapshot.c | 24 +++++++++++++++++++++++- 1 file changed, 23 insertions(+), 1 deletion(-) diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c index 98c3b34..e6db5a8 100644 --- a/kernel/power/snapshot.c +++ b/kernel/power/snapshot.c @@ -730,6 +730,28 @@ static void mark_nosave_pages(struct memory_bitmap *bm) } } +static bool is_nosave_page(unsigned long pfn) +{ + struct nosave_region *region; + + if (list_empty(&nosave_regions)) + return 0; + + list_for_each_entry(region, &nosave_regions, list) { + if (pfn >= region->start_pfn && pfn < region->end_pfn) { + pr_err("PM: %#010llx in e820 nosave regsion: " + "[mem %#010llx-%#010llx]\n", + (unsigned long long) pfn << PAGE_SHIFT, + (unsigned long long) region->start_pfn << PAGE_SHIFT, + ((unsigned long long) region->end_pfn << PAGE_SHIFT) + - 1); + return true; + } + } + + return false; +} + /** * create_basic_memory_bitmaps - create bitmaps needed for marking page * frames that should not be saved and free page frames. The pointers @@ -1769,7 +1791,7 @@ static int mark_unsafe_pages(struct memory_bitmap *bm) do { pfn = memory_bm_next_pfn(bm); if (likely(pfn != BM_END_OF_MAP)) { - if (likely(pfn_valid(pfn))) + if (likely(pfn_valid(pfn)) && !is_nosave_page(pfn)) swsusp_set_page_free(pfn_to_page(pfn)); else return -EFAULT;