From patchwork Thu May 23 06:34:24 2019
Content-Type: text/plain; charset="utf-8"
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
X-Patchwork-Submitter: Paul Mackerras <paulus@ozlabs.org>
X-Patchwork-Id: 10956933
Return-Path: <kvm-owner@kernel.org>
Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org
 [172.30.200.125])
	by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 943F113AD
	for <patchwork-kvm@patchwork.kernel.org>;
 Thu, 23 May 2019 06:36:48 +0000 (UTC)
Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1])
	by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6D5A927FA5
	for <patchwork-kvm@patchwork.kernel.org>;
 Thu, 23 May 2019 06:36:48 +0000 (UTC)
Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486)
	id 61335280CF; Thu, 23 May 2019 06:36:48 +0000 (UTC)
X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on
	pdx-wl-mail.web.codeaurora.org
X-Spam-Level: 
X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED,
	DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham
	version=3.3.1
Received: from vger.kernel.org (vger.kernel.org [209.132.180.67])
	by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 0A48027FA5
	for <patchwork-kvm@patchwork.kernel.org>;
 Thu, 23 May 2019 06:36:47 +0000 (UTC)
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
        id S1727428AbfEWGgp (ORCPT
        <rfc822;patchwork-kvm@patchwork.kernel.org>);
        Thu, 23 May 2019 02:36:45 -0400
Received: from ozlabs.org ([203.11.71.1]:59401 "EHLO ozlabs.org"
        rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP
        id S1725814AbfEWGgp (ORCPT <rfc822;kvm@vger.kernel.org>);
        Thu, 23 May 2019 02:36:45 -0400
Received: by ozlabs.org (Postfix, from userid 1003)
        id 458ft32BtBz9s6w; Thu, 23 May 2019 16:36:43 +1000 (AEST)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ozlabs.org; s=201707;
        t=1558593403; bh=i2k9PFZzZY81TWnMP3MoNOhrPgt9F0xczRulArBIXkE=;
        h=Date:From:To:Cc:Subject:From;
        b=RabZLyM8v2pxuSqruwfRDYUClybUf8RX0yqio4LRDYSF81zQaUN0E2KRpMVN4RSoJ
         zaSDvHB4cODGQOqPtkhYc2EYxZHlMKt7ImhFaQEDYZwbMDy1xtd+habJo0oR9ZJPFK
         C/zaCyfVUBLuiAVBCdzQjUgB008eeG0ONSVmvo2g8y8zHTpkFTPAqNudHPCCOtjlif
         BTrhXDmLsfdIf4b89Uk5BpGp9983clLISJnbcVQbNFle1Hfdnib5T+4zWXrVLI49QQ
         XaECcnb4Kwpunv89lIjLOSfpWSVDw1NGWie/oc5X3rn6RKjGvgK86PDc2F77xzSYCf
         ESNXxECFMT5cA==
Date: Thu, 23 May 2019 16:34:24 +1000
From: Paul Mackerras <paulus@ozlabs.org>
To: kvm@vger.kernel.org
Cc: kvm-ppc@vger.kernel.org,
 =?iso-8859-1?q?C=E9dric?= Le Goater <clg@kaod.org>
Subject: [PATCH 0/4] KVM: PPC: Book3S: Fix potential deadlocks
Message-ID: <20190523063424.GB19655@blackberry>
MIME-Version: 1.0
Content-Disposition: inline
User-Agent: Mutt/1.5.24 (2015-08-30)
Sender: kvm-owner@vger.kernel.org
Precedence: bulk
List-ID: <kvm.vger.kernel.org>
X-Mailing-List: kvm@vger.kernel.org
X-Virus-Scanned: ClamAV using ClamSMTP

Recent reports of lockdep splats in the HV KVM code revealed that it
was taking the kvm->lock mutex in several contexts where a vcpu mutex
was already held.  Lockdep has only started warning since I added code
to take the vcpu mutexes in the XIVE device release functions, but
since Documentation/virtual/kvm/locking.txt specifies that the vcpu
mutexes nest inside kvm->lock, it seems that the new code is correct
and it is most of the old uses of kvm->lock that are wrong.

This series should fix the problems, by adding new mutexes that nest
inside the vcpu mutexes and using them instead of kvm->lock.

Paul.