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=-0.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 9178DC35E0B for ; Tue, 25 Feb 2020 16:09:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6859E2176D for ; Tue, 25 Feb 2020 16:09:30 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="PeFnmIXi" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731067AbgBYQJa (ORCPT ); Tue, 25 Feb 2020 11:09:30 -0500 Received: from mail-il1-f170.google.com ([209.85.166.170]:42190 "EHLO mail-il1-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729206AbgBYQJ3 (ORCPT ); Tue, 25 Feb 2020 11:09:29 -0500 Received: by mail-il1-f170.google.com with SMTP id x2so1789115ila.9; Tue, 25 Feb 2020 08:09:29 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:from:date:message-id:subject:to:cc :content-transfer-encoding; bh=bBxq4NlVT2GPfEQHH0hn7IMMrqDvaebxrDPcHRUCmVQ=; b=PeFnmIXiaQXXC1hZoM2/FOQBtn4LarKDEsvjyiZrpzK8iw4E2UVlU4HH6GpvmSJ0y7 QJn1ZR4PP1964p1H5cLyiT0sKiJNQzovc3IPNX8n5g5gEAQN50Sp9zfCmJhIFMvtagof dTtLM0YWVOjwcEiqJzXm+hYalT96GGAe9+EF5qKCKZl+iguohVhoKoAcIoQ08OQkEMxA ALEa/qUjspBz+wPiwYccxf1fDZ+xoNAhzOwMH4wQw3bhA58gt14q6Yij9EybV4l2j/4J C1kQywJDY+v3PgdSk8tdMIuLKv2ei3cbYw5GgUfa6qNnzg0zifB/9r/myR49kD5J54xQ gKjQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:from:date:message-id:subject:to:cc :content-transfer-encoding; bh=bBxq4NlVT2GPfEQHH0hn7IMMrqDvaebxrDPcHRUCmVQ=; b=X72hpqH4SRIzYikUDSw0G6covFB+QA4x6OOij2Er9InLESR9/jweXL3xk4q3cPCvdz IEZXLREG/GpubAJhVVYfS5N29nBbm6iCkQQ4ZwGmKBLOBb7OiEVOz52BTLHgRzq3MRgx zAqEhGKTo6HjfZoNjqntRDZ8jsQywwwBrcZuasjmjWEQsqeG9PZu4sSlSmD8r2Uzxk6i SwjeS5dBeYM5HcZaMdRQ7BOamQrLrZN3jiiEkSqfKodlyrKzbFgmvo9MOJp88LwRC2HB sFLveWSGGujUWVHptpIZCrRNyvEFtwbfFPaQAQQVSaueWR7l0+Pyn/sYOZi7/belSSeb guxw== X-Gm-Message-State: APjAAAUzw+24T2KQ9TIFTqBHVh3heNjdyuRKvvvFpWVifabwwj+KmEeV DIxsrayOqkCW6PTZd1s92rMqXHZmNUXajtbWm9dn935D X-Google-Smtp-Source: APXvYqzihMF67D637iOTQRASMq8d5Y/DQGqcGg8S2RvIEt9WmGR4Nnm1bzUynkgr5HxgldJSaZFAARvggtgly0kO3Zo= X-Received: by 2002:a92:b749:: with SMTP id c9mr67810506ilm.143.1582646968592; Tue, 25 Feb 2020 08:09:28 -0800 (PST) MIME-Version: 1.0 From: Wayne Li Date: Tue, 25 Feb 2020 10:09:17 -0600 Message-ID: Subject: Problem with virtual to physical memory translation when KVM is enabled. To: kvm@vger.kernel.org, kvm-ppc@vger.kernel.org Cc: David Gibson , qemu-ppc@nongnu.org, QEMU Developers Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Dear KVM list members, We developed a virtual machine using the QEMU code. This virtual machine emulates a certain custom-made computer that runs on a certain military platform. All I can tell you about this virtual machine is that it emulates a computer that has an e5500 processor. Currently I am running this virtual machine on a T4240-RDB which has a PowerPC e6500 processor. Anyway, right now I=E2=80=99m trying to get this virtual machine working wi= th KVM enabled. But the problem I=E2=80=99m having is the VM doesn=E2=80=99t = do anything after the KVM_RUN ioctl call is made (NIP doesn=E2=80=99t progress and no registers change). What seems to be the problem is the VM doesn=E2=80=99t = run the instruction that=E2=80=99s supposed to be retrieved from the virtual address 0xFFFF_FFFC. When KVM isn=E2=80=99t enabled and the VM is running using TCG (tiny code generator), a branch instruction to 0xFFFF_F700 is retrieved from the virtual address 0xFFFF_FFFC and the VM kicks off running from there. So what could be causing this problem? I=E2=80=99m guessing it has somethi= ng to do with the translation lookaside buffers (TLBs)? But the translation between virtual and physical memory clearly works when KVM isn=E2=80=99t enabled. So what could cause this to stop working when KVM i= s enabled? Or maybe I=E2=80=99m not understanding something right and missin= g what the problem actually is? Let me know your thoughts. -Thanks, Wayne Li