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=-11.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,MAILING_LIST_MULTI,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 061D8C4707A for ; Fri, 21 May 2021 17:50:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D54E761353 for ; Fri, 21 May 2021 17:50:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238659AbhEURvw (ORCPT ); Fri, 21 May 2021 13:51:52 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:39550 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238824AbhEURux (ORCPT ); Fri, 21 May 2021 13:50:53 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1621619369; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=eCxGfuMnfQDDRkSgoJFFHxNWdySUYed2Pe05f2luAA0=; b=aE9Sc92hXStN9ZqL4gRhzkm+G8kJ15IhSfpZLMkD3rSX5ioz/SeXekAaGD3fSdiaTj62A/ +JNZqwNYlrKAtR/zETxaoa2v5Y1HfqUdjmGgkE4quO6BjdbfjmgO+upi7Y+DtH2I3b1+r0 G0SyMLyNdEMvUUYGD1LMmZ93esgV8zY= Received: from mail-qt1-f197.google.com (mail-qt1-f197.google.com [209.85.160.197]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-404-VK99emozMOi3f4VMr68mkg-1; Fri, 21 May 2021 13:49:27 -0400 X-MC-Unique: VK99emozMOi3f4VMr68mkg-1 Received: by mail-qt1-f197.google.com with SMTP id j12-20020ac8550c0000b02901dae492d1f2so16152740qtq.0 for ; Fri, 21 May 2021 10:49:27 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=eCxGfuMnfQDDRkSgoJFFHxNWdySUYed2Pe05f2luAA0=; b=gNqX9X2aiOJ6QfPs4HYF35ZR2H8YYXr4E8pIa/7MBnO8h/GNMvcjwecd8dkgldKnZV szEHTFuUVsrwj4D7JOGSovvhaPnSg8AceINPEVQ70lR9bT7dB24dDGK4o1/4EIaP6uy9 pTpr91/8hBx44jkrW6m5mfyS6xYyQpwp5QMwpx6K/skTc3ZQmf0eoLqiOKz16d0unQqW VfCtQjE4SniOFIce31frzJom8nXAl6/DfTX/tIJKA2oSThgsE9RdTEzoJXBdmjtPymDx jLhsVN6wF6xxQnufIy0DPEPWEmWqPxFkbQ8exDyAJJktmKyaQ6H0CJ3OWigdixbZGvu2 Vfxg== X-Gm-Message-State: AOAM530NYecA1cd0hsvvCpoDqEoLF4qb6hdU86gD96MhHhq3p2FULDAp l5U0vxstEkTgluqopuUI2uNxvKi5B17gNi9zkX/NiQgeBkQrKUZgmJmF4Fqmw5ennFry1wfT5eq J/NnjNQBmWtse X-Received: by 2002:a05:620a:208a:: with SMTP id e10mr13819708qka.112.1621619367404; Fri, 21 May 2021 10:49:27 -0700 (PDT) X-Google-Smtp-Source: ABdhPJzIWrFiYBNV1lMWqMFypLd73cRUR7XXcI8n00vyqQX8k2WQLOZv+V4f4cwC6ev7eFBBG1MJxQ== X-Received: by 2002:a05:620a:208a:: with SMTP id e10mr13819684qka.112.1621619367136; Fri, 21 May 2021 10:49:27 -0700 (PDT) Received: from t490s (bras-base-toroon474qw-grc-72-184-145-4-219.dsl.bell.ca. [184.145.4.219]) by smtp.gmail.com with ESMTPSA id g1sm4791195qtr.32.2021.05.21.10.49.26 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 21 May 2021 10:49:26 -0700 (PDT) Date: Fri, 21 May 2021 13:49:25 -0400 From: Peter Xu To: David Matlack Cc: kvm@vger.kernel.org, Venkatesh Srinivas , Paolo Bonzini , Andrew Jones , Ben Gardon Subject: Re: [PATCH v2] KVM: selftests: Fix 32-bit truncation of vm_get_max_gfn() Message-ID: References: <20210521173828.1180619-1-dmatlack@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20210521173828.1180619-1-dmatlack@google.com> Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Fri, May 21, 2021 at 05:38:28PM +0000, David Matlack wrote: > vm_get_max_gfn() casts vm->max_gfn from a uint64_t to an unsigned int, > which causes the upper 32-bits of the max_gfn to get truncated. > > Nobody noticed until now likely because vm_get_max_gfn() is only used > as a mechanism to create a memslot in an unused region of the guest > physical address space (the top), and the top of the 32-bit physical > address space was always good enough. > > This fix reveals a bug in memslot_modification_stress_test which was > trying to create a dummy memslot past the end of guest physical memory. > Fix that by moving the dummy memslot lower. > > Fixes: 52200d0d944e ("KVM: selftests: Remove duplicate guest mode handling") > Reviewed-by: Venkatesh Srinivas > Signed-off-by: David Matlack Reviewed-by: Peter Xu -- Peter Xu