From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759264AbbA3D6j (ORCPT ); Thu, 29 Jan 2015 22:58:39 -0500 Received: from mail-pa0-f53.google.com ([209.85.220.53]:64926 "EHLO mail-pa0-f53.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751401AbbA3D6i (ORCPT ); Thu, 29 Jan 2015 22:58:38 -0500 From: "Lee, Chun-Yi" X-Google-Original-From: "Lee, Chun-Yi" To: "Rafael J. Wysocki" , Ingo Molnar , Pavel Machek Cc: Thomas Gleixner , x86@kernel.org, linux-kernel@vger.kernel.org, "Lee, Chun-Yi" , Len Brown , "H. Peter Anvin" , Yinghai Lu , Takashi Iwai Subject: [PATCH] x86/mm, hibernate: Fix misjudgment of register setup_data page to nosave region Date: Fri, 30 Jan 2015 11:58:20 +0800 Message-Id: <1422590300-13307-1-git-send-email-jlee@suse.com> X-Mailer: git-send-email 1.8.4.5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The reserve setup_data action break usable regions to not align to page size. As following case: BIOS-e820: [mem 0x0000000000088000-0x00000000000bffff] reserved BIOS-e820: [mem 0x0000000000100000-0x0000000094caffff] usable ... e820: update [mem 0x93c5f018-0x93c6f057] usable ==> usable /* reserve setup_data */ e820: update [mem 0x93c4f018-0x93c5e057] usable ==> usable /* reserve setup_data */ ... reserve setup_data: [mem0x0000000000088000-0x00000000000bffff] reserved reserve setup_data: [mem0x0000000000100000-0x0000000093c4f017] usable /* not align */ reserve setup_data: [mem0x0000000093c4f018-0x0000000093c5e057] usable /* not align */ reserve setup_data: [mem0x0000000093c5e058-0x0000000093c5f017] usable /* not align */ reserve setup_data: [mem0x0000000093c5f018-0x0000000093c6f057] usable /* not align */ reserve setup_data: [mem0x0000000093c6f058-0x0000000094caffff] usable The codes in e820_mark_nosave_regions() check pfn of each e820 entry to find out the hole between two entries then register it to nosave region. This logic misjudges the non-align but continuous usable region, then register one page in usable region to nosave. As following: PM: Registered nosave memory: [mem 0x000c0000-0x000fffff] PM: Registered nosave memory: [mem 0x93c4f000-0x93c4ffff] /* misjudgment */ PM: Registered nosave memory: [mem 0x93c5e000-0x93c5efff] /* misjudgment */ PM: Registered nosave memory: [mem 0x93c5f000-0x93c5ffff] /* misjudgment */ PM: Registered nosave memory: [mem 0x93c6f000-0x93c6ffff] /* misjudgment */ PM: Registered nosave memory: [mem 0x94cb0000-0x960affff] The issue causes some usable pages didn't collect to hibernate snapshot image. And, it also misjudges a usable page in nosave regions then hibernate resuming process interrupted by the unsafe pages checking: https://bugzilla.opensuse.org/show_bug.cgi?id=913885 This patch changed the code in e820_mark_nosave_regions() to check the address instead of pfn to avoid above issue. Cc: Pavel Machek Cc: "Rafael J. Wysocki" Cc: Len Brown Cc: "H. Peter Anvin" Cc: Yinghai Lu Cc: Takashi Iwai Cc: Ingo Molnar Signed-off-by: Lee, Chun-Yi --- arch/x86/kernel/e820.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c index 49f8864..6eae021 100644 --- a/arch/x86/kernel/e820.c +++ b/arch/x86/kernel/e820.c @@ -687,15 +687,16 @@ void __init parse_e820_ext(u64 phys_addr, u32 data_len) void __init e820_mark_nosave_regions(unsigned long limit_pfn) { int i; - unsigned long pfn = 0; + unsigned long pfn = 0, pfnaddr = 0; for (i = 0; i < e820.nr_map; i++) { struct e820entry *ei = &e820.map[i]; - if (pfn < PFN_UP(ei->addr)) + if (pfnaddr < ei->addr) register_nosave_region(pfn, PFN_UP(ei->addr)); - pfn = PFN_DOWN(ei->addr + ei->size); + pfnaddr = ei->addr + ei->size; + pfn = PFN_DOWN(pfnaddr); if (ei->type != E820_RAM && ei->type != E820_RESERVED_KERN) register_nosave_region(PFN_UP(ei->addr), pfn); -- 1.8.4.5