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=-5.7 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_ADSP_ALL, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 D29F6C742D1 for ; Fri, 12 Jul 2019 15:58:35 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id AC0722166E for ; Fri, 12 Jul 2019 15:58:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="YQKE0axN"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=amazon.de header.i=@amazon.de header.b="iiavQVDX" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AC0722166E Authentication-Results: mail.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=amazon.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:Content-ID:In-Reply-To: References:Message-ID:Date:Subject:To:From:Reply-To:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=/oEz4xjyGgwzdwlM67pmZiCLjWYK9y8seVWgwgdiYBI=; b=YQKE0axNiemYvP W0VRO0gMxs16ZtQ2I09huAYJhOfhD8SNzZsPhm/cCxMcn7UrhegcGtWRhlp2ncfsDgXmiQ2X1MHXf 8UMXKQkgCPf+ImufXa800onZYSWlHuUiSnNCep7WT+6GH8a8+bRsTJPCQgGh+RLh+txrbR/fuvda8 1LeALxpqxHd+oTaIfTzy9rMRhpzS1gcrMwjKZF+QmuuzRI/pFvLoYrAtATgGOqfByX0O/yoE7PiZn hQnXhWtBShbYyfiiMA1jlyhUwqaygwbW6Oivy5EmqWZ1VhOoPleypYZnRgT4lKBUFSmEiKH02mYrv tGnemAFxPGytwqJsMfag==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92 #3 (Red Hat Linux)) id 1hlxwP-0007Qr-KA; Fri, 12 Jul 2019 15:58:33 +0000 Received: from smtp-fw-33001.amazon.com ([207.171.190.10]) by bombadil.infradead.org with esmtps (Exim 4.92 #3 (Red Hat Linux)) id 1hlxwM-0007Q5-10 for linux-arm-kernel@lists.infradead.org; Fri, 12 Jul 2019 15:58:31 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.de; i=@amazon.de; q=dns/txt; s=amazon201209; t=1562947109; x=1594483109; h=from:to:cc:subject:date:message-id:references: in-reply-to:content-id:mime-version: content-transfer-encoding; bh=Xv6oMdRCDU5+Rbt92DK7ZqXDl23JyeTh31Mje6oJEeA=; b=iiavQVDXsfKYvtjb7AVbbq5zd8PPT9jaocdsU3LJ8SOBHOaD2IePIVpA inGN1kXir/lbAYBBE9D4HHVhaCfpcDp1Zu8jseGM/dF2RaQ2qWfja9Cz5 cAvfkVllJ2cwW3qHFn9nn0otncWPgB8UBakvanPXLS6+OzR4DBqZZ7i6B s=; X-IronPort-AV: E=Sophos;i="5.62,483,1554768000"; d="scan'208";a="810893324" Received: from sea3-co-svc-lb6-vlan3.sea.amazon.com (HELO email-inbound-relay-2c-168cbb73.us-west-2.amazon.com) ([10.47.22.38]) by smtp-border-fw-out-33001.sea14.amazon.com with ESMTP; 12 Jul 2019 15:58:25 +0000 Received: from EX13MTAUEA001.ant.amazon.com (pdx4-ws-svc-p6-lb7-vlan2.pdx.amazon.com [10.170.41.162]) by email-inbound-relay-2c-168cbb73.us-west-2.amazon.com (Postfix) with ESMTPS id 819EEA2452; Fri, 12 Jul 2019 15:58:25 +0000 (UTC) Received: from EX13D01EUB003.ant.amazon.com (10.43.166.248) by EX13MTAUEA001.ant.amazon.com (10.43.61.82) with Microsoft SMTP Server (TLS) id 15.0.1367.3; Fri, 12 Jul 2019 15:58:24 +0000 Received: from EX13D01EUB003.ant.amazon.com (10.43.166.248) by EX13D01EUB003.ant.amazon.com (10.43.166.248) with Microsoft SMTP Server (TLS) id 15.0.1367.3; Fri, 12 Jul 2019 15:58:24 +0000 Received: from EX13D01EUB003.ant.amazon.com ([10.43.166.248]) by EX13D01EUB003.ant.amazon.com ([10.43.166.248]) with mapi id 15.00.1367.000; Fri, 12 Jul 2019 15:58:24 +0000 From: "Raslan, KarimAllah" To: "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH] KVM: arm/arm64: Properly check for MMIO regions Thread-Topic: [PATCH] KVM: arm/arm64: Properly check for MMIO regions Thread-Index: AQHVOIsEiyNRFKEvKk+KpgFJVWRN7KbHJC2A Date: Fri, 12 Jul 2019 15:58:23 +0000 Message-ID: <1562947103.19043.1.camel@amazon.de> References: <1562919728-642-1-git-send-email-karahmed@amazon.de> In-Reply-To: <1562919728-642-1-git-send-email-karahmed@amazon.de> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.43.165.54] Content-ID: <5D2353EA90095E4081DA8A6D66A19A79@amazon.com> MIME-Version: 1.0 Precedence: Bulk X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190712_085830_130950_A1ADBB0A X-CRM114-Status: GOOD ( 20.58 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: "marc.zyngier@arm.com" , "suzuki.poulose@arm.com" , "james.morse@arm.com" , "kvmarm@lists.cs.columbia.edu" , "julien.thierry@arm.com" Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, 2019-07-12 at 10:22 +0200, KarimAllah Ahmed wrote: > Valid RAM can live outside kernel control (e.g. using "mem=" command-line > parameter). This memory can still be used as valid guest memory for KVM. So > ensure that we validate that this memory is definitely not "RAM" before > assuming that it is an MMIO region. This patch actually suffers from the same problem pointed out here: https://lkml.org/lkml/2019/7/12/760 .. so I will need to rework them together. > > One way to use memory outside kernel control is: > > 1- Pass 'mem=' in the kernel command-line to limit the amount of memory managed > by the kernel. > 2- Map this physical memory you want to give to the guest with: > mmap("/dev/mem", physical_address_offset, ..) > 3- Use the user-space virtual address as the "userspace_addr" field in > KVM_SET_USER_MEMORY_REGION ioctl. > > One of the limitations of the current /dev/mem for ARM is that it would map > this memory as uncached without this patch: > https://lkml.org/lkml/2019/7/11/684 > > This work is similar to the work done on x86 here: > https://lkml.org/lkml/2019/1/31/933 > > Cc: Marc Zyngier > Cc: James Morse > Cc: Julien Thierry > Cc: Suzuki K Pouloze > Cc: linux-arm-kernel@lists.infradead.org > Cc: kvmarm@lists.cs.columbia.edu > Cc: linux-kernel@vger.kernel.org > Signed-off-by: KarimAllah Ahmed > --- > virt/kvm/arm/mmu.c | 18 ++++++++++++------ > 1 file changed, 12 insertions(+), 6 deletions(-) > > diff --git a/virt/kvm/arm/mmu.c b/virt/kvm/arm/mmu.c > index 06180c9..2105134 100644 > --- a/virt/kvm/arm/mmu.c > +++ b/virt/kvm/arm/mmu.c > @@ -8,6 +8,7 @@ > #include > #include > #include > +#include > #include > #include > #include > @@ -89,7 +90,7 @@ static void kvm_flush_dcache_pud(struct kvm *kvm, > > static bool kvm_is_device_pfn(unsigned long pfn) > { > - return !pfn_valid(pfn); > + return !memblock_is_memory(__pfn_to_phys(pfn)); > } > > /** > @@ -949,6 +950,7 @@ static void stage2_unmap_memslot(struct kvm *kvm, > do { > struct vm_area_struct *vma = find_vma(current->mm, hva); > hva_t vm_start, vm_end; > + gpa_t gpa; > > if (!vma || vma->vm_start >= reg_end) > break; > @@ -959,11 +961,14 @@ static void stage2_unmap_memslot(struct kvm *kvm, > vm_start = max(hva, vma->vm_start); > vm_end = min(reg_end, vma->vm_end); > > - if (!(vma->vm_flags & VM_PFNMAP)) { > - gpa_t gpa = addr + (vm_start - memslot->userspace_addr); > - unmap_stage2_range(kvm, gpa, vm_end - vm_start); > - } > hva = vm_end; > + > + if ((vma->vm_flags & VM_PFNMAP) && > + !memblock_is_memory(__pfn_to_phys(vma->vm_pgoff))) > + continue; > + > + gpa = addr + (vm_start - memslot->userspace_addr); > + unmap_stage2_range(kvm, gpa, vm_end - vm_start); > } while (hva < reg_end); > } > > @@ -2329,7 +2334,8 @@ int kvm_arch_prepare_memory_region(struct kvm *kvm, > vm_start = max(hva, vma->vm_start); > vm_end = min(reg_end, vma->vm_end); > > - if (vma->vm_flags & VM_PFNMAP) { > + if ((vma->vm_flags & VM_PFNMAP) && > + !memblock_is_memory(__pfn_to_phys(vma->vm_pgoff))) { > gpa_t gpa = mem->guest_phys_addr + > (vm_start - mem->userspace_addr); > phys_addr_t pa; Amazon Development Center Germany GmbH Krausenstr. 38 10117 Berlin Geschaeftsfuehrung: Christian Schlaeger, Ralf Herbrich Eingetragen am Amtsgericht Charlottenburg unter HRB 149173 B Sitz: Berlin Ust-ID: DE 289 237 879 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel