From patchwork Fri Mar 20 12:21:37 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Igor Mammedov X-Patchwork-Id: 6056101 Return-Path: X-Original-To: patchwork-kvm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id D94509F399 for ; Fri, 20 Mar 2015 12:22:11 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id ED60520520 for ; Fri, 20 Mar 2015 12:22:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0D05C20519 for ; Fri, 20 Mar 2015 12:22:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751293AbbCTMVx (ORCPT ); Fri, 20 Mar 2015 08:21:53 -0400 Received: from mx1.redhat.com ([209.132.183.28]:38901 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751142AbbCTMVx (ORCPT ); Fri, 20 Mar 2015 08:21:53 -0400 Received: from int-mx10.intmail.prod.int.phx2.redhat.com (int-mx10.intmail.prod.int.phx2.redhat.com [10.5.11.23]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id t2KCLiSl008760 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Fri, 20 Mar 2015 08:21:44 -0400 Received: from dell-pet610-01.lab.eng.brq.redhat.com (dell-pet610-01.lab.eng.brq.redhat.com [10.34.42.20]) by int-mx10.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id t2KCLgQu009803; Fri, 20 Mar 2015 08:21:42 -0400 From: Igor Mammedov To: linux-kernel@vger.kernel.org Cc: himbeere@meine-oma.de, mimi.vx@gmail.com, bsd@makefile.in, mtosatti@redhat.com, kvm@vger.kernel.org Subject: [PATCH v2] kvm: avoid page allocation failure in kvm_set_memory_region() Date: Fri, 20 Mar 2015 12:21:37 +0000 Message-Id: <1426854097-22210-1-git-send-email-imammedo@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.23 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, T_RP_MATCHES_RCVD, 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 KVM guest can fail to startup with following trace on host: qemu-system-x86: page allocation failure: order:4, mode:0x40d0 Call Trace: dump_stack+0x47/0x67 warn_alloc_failed+0xee/0x150 __alloc_pages_direct_compact+0x14a/0x150 __alloc_pages_nodemask+0x776/0xb80 alloc_kmem_pages+0x3a/0x110 kmalloc_order+0x13/0x50 kmemdup+0x1b/0x40 __kvm_set_memory_region+0x24a/0x9f0 [kvm] kvm_set_ioapic+0x130/0x130 [kvm] kvm_set_memory_region+0x21/0x40 [kvm] kvm_vm_ioctl+0x43f/0x750 [kvm] Failure happens when attempting to allocate pages for 'struct kvm_memslots', however it doesn't have to be present in physically contiguous (kmalloc-ed) address space, change allocation to kvm_kvzalloc() so that it will be vmalloc-ed when its size is more then a page. Signed-off-by: Igor Mammedov --- v2: - alloc initial memslots with vmalloc - use kvfree in every place where memslots are freed TODO: - work on follow up patches to allocate space for actual amount of memory_slots instead of possible maximum. --- virt/kvm/kvm_main.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index a2214d9..cc6a25d 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -471,7 +471,7 @@ static struct kvm *kvm_create_vm(unsigned long type) BUILD_BUG_ON(KVM_MEM_SLOTS_NUM > SHRT_MAX); r = -ENOMEM; - kvm->memslots = kzalloc(sizeof(struct kvm_memslots), GFP_KERNEL); + kvm->memslots = kvm_kvzalloc(sizeof(struct kvm_memslots)); if (!kvm->memslots) goto out_err_no_srcu; @@ -522,7 +522,7 @@ out_err_no_srcu: out_err_no_disable: for (i = 0; i < KVM_NR_BUSES; i++) kfree(kvm->buses[i]); - kfree(kvm->memslots); + kvfree(kvm->memslots); kvm_arch_free_vm(kvm); return ERR_PTR(r); } @@ -578,7 +578,7 @@ static void kvm_free_physmem(struct kvm *kvm) kvm_for_each_memslot(memslot, slots) kvm_free_physmem_slot(kvm, memslot, NULL); - kfree(kvm->memslots); + kvfree(kvm->memslots); } static void kvm_destroy_devices(struct kvm *kvm) @@ -871,10 +871,10 @@ int __kvm_set_memory_region(struct kvm *kvm, goto out_free; } - slots = kmemdup(kvm->memslots, sizeof(struct kvm_memslots), - GFP_KERNEL); + slots = kvm_kvzalloc(sizeof(struct kvm_memslots)); if (!slots) goto out_free; + memcpy(slots, kvm->memslots, sizeof(struct kvm_memslots)); if ((change == KVM_MR_DELETE) || (change == KVM_MR_MOVE)) { slot = id_to_memslot(slots, mem->slot); @@ -917,7 +917,7 @@ int __kvm_set_memory_region(struct kvm *kvm, kvm_arch_commit_memory_region(kvm, mem, &old, change); kvm_free_physmem_slot(kvm, &old, &new); - kfree(old_memslots); + kvfree(old_memslots); /* * IOMMU mapping: New slots need to be mapped. Old slots need to be @@ -936,7 +936,7 @@ int __kvm_set_memory_region(struct kvm *kvm, return 0; out_slots: - kfree(slots); + kvfree(slots); out_free: kvm_free_physmem_slot(kvm, &new, &old); out: