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 X-Spam-Level: X-Spam-Status: No, score=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D7747C282D5 for ; Wed, 30 Jan 2019 08:22:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AFB0921874 for ; Wed, 30 Jan 2019 08:22:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730285AbfA3IWm (ORCPT ); Wed, 30 Jan 2019 03:22:42 -0500 Received: from mx2.suse.de ([195.135.220.15]:52758 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726583AbfA3IWj (ORCPT ); Wed, 30 Jan 2019 03:22:39 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 4AD2FB0EF; Wed, 30 Jan 2019 08:22:37 +0000 (UTC) From: Juergen Gross To: linux-kernel@vger.kernel.org, xen-devel@lists.xenproject.org, x86@kernel.org, linux-mm@kvack.org Cc: boris.ostrovsky@oracle.com, sstabellini@kernel.org, hpa@zytor.com, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, Juergen Gross Subject: [PATCH v2 2/2] x86/xen: dont add memory above max allowed allocation Date: Wed, 30 Jan 2019 09:22:33 +0100 Message-Id: <20190130082233.23840-3-jgross@suse.com> X-Mailer: git-send-email 2.16.4 In-Reply-To: <20190130082233.23840-1-jgross@suse.com> References: <20190130082233.23840-1-jgross@suse.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Don't allow memory to be added above the allowed maximum allocation limit set by Xen. Trying to do so would result in cases like the following: [ 584.559652] ------------[ cut here ]------------ [ 584.564897] WARNING: CPU: 2 PID: 1 at ../arch/x86/xen/multicalls.c:129 xen_alloc_pte+0x1c7/0x390() [ 584.575151] Modules linked in: [ 584.578643] Supported: Yes [ 584.581750] CPU: 2 PID: 1 Comm: swapper/0 Not tainted 4.4.120-92.70-default #1 [ 584.590000] Hardware name: Cisco Systems Inc UCSC-C460-M4/UCSC-C460-M4, BIOS C460M4.4.0.1b.0.0629181419 06/29/2018 [ 584.601862] 0000000000000000 ffffffff813175a0 0000000000000000 ffffffff8184777c [ 584.610200] ffffffff8107f4e1 ffff880487eb7000 ffff8801862b79c0 ffff88048608d290 [ 584.618537] 0000000000487eb7 ffffea0000000201 ffffffff81009de7 ffffffff81068561 [ 584.626876] Call Trace: [ 584.629699] [] dump_trace+0x59/0x340 [ 584.635645] [] show_stack_log_lvl+0xea/0x170 [ 584.642391] [] show_stack+0x21/0x40 [ 584.648238] [] dump_stack+0x5c/0x7c [ 584.654085] [] warn_slowpath_common+0x81/0xb0 [ 584.660932] [] xen_alloc_pte+0x1c7/0x390 [ 584.667289] [] pmd_populate_kernel.constprop.6+0x40/0x80 [ 584.675241] [] phys_pmd_init+0x210/0x255 [ 584.681587] [] phys_pud_init+0x1da/0x247 [ 584.687931] [] kernel_physical_mapping_init+0xf5/0x1d4 [ 584.695682] [] init_memory_mapping+0x18d/0x380 [ 584.702631] [] arch_add_memory+0x59/0xf0 Signed-off-by: Juergen Gross --- arch/x86/xen/setup.c | 10 ++++++++++ drivers/xen/xen-balloon.c | 6 ++++++ 2 files changed, 16 insertions(+) diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c index d5f303c0e656..fdb184cadaf5 100644 --- a/arch/x86/xen/setup.c +++ b/arch/x86/xen/setup.c @@ -12,6 +12,7 @@ #include #include #include +#include #include #include @@ -825,6 +826,15 @@ char * __init xen_memory_setup(void) xen_max_p2m_pfn = pfn_s + n_pfns; } else discard = true; +#ifdef CONFIG_MEMORY_HOTPLUG + /* + * Don't allow adding memory not in E820 map while + * booting the system. Once the balloon driver is up + * it will remove that restriction again. + */ + max_mem_size = xen_e820_table.entries[i].addr + + xen_e820_table.entries[i].size; +#endif } if (!discard) diff --git a/drivers/xen/xen-balloon.c b/drivers/xen/xen-balloon.c index 2acbfe104e46..2a960fcc812e 100644 --- a/drivers/xen/xen-balloon.c +++ b/drivers/xen/xen-balloon.c @@ -37,6 +37,7 @@ #include #include #include +#include #include #include @@ -63,6 +64,11 @@ static void watch_target(struct xenbus_watch *watch, static bool watch_fired; static long target_diff; +#ifdef CONFIG_MEMORY_HOTPLUG + /* The balloon driver will take care of adding memory now. */ + max_mem_size = U64_MAX; +#endif + err = xenbus_scanf(XBT_NIL, "memory", "target", "%llu", &new_target); if (err != 1) { /* This is ok (for domain0 at least) - so just return */ -- 2.16.4