From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andres Lagar-Cavilla Subject: [PATCH 2 of 8] x86/mm: Fix p2m teardown locking Date: Wed, 25 Jan 2012 22:53:26 -0500 Message-ID: <2e7c77585adbb6aa3f04.1327550006@xdev.gridcentric.ca> References: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: xen-devel@lists.xensource.com Cc: olaf@aepfle.de, tim@xen.org, andres@gridcentric.ca, adin@gridcentric.ca List-Id: xen-devel@lists.xenproject.org xen/arch/x86/mm/p2m.c | 4 ++-- 1 files changed, 2 insertions(+), 2 deletions(-) Holding the p2m lock during a p2m teardown, while unsharing entries pointing to shared frames, causes a locking inversion and deadlock panic. Signed-off-by: Andres Lagar-Cavilla diff -r 143e4982c9bf -r 2e7c77585adb xen/arch/x86/mm/p2m.c --- a/xen/arch/x86/mm/p2m.c +++ b/xen/arch/x86/mm/p2m.c @@ -343,8 +343,6 @@ void p2m_teardown(struct p2m_domain *p2m if (p2m == NULL) return; - p2m_lock(p2m); - #ifdef __x86_64__ for ( gfn=0; gfn < p2m->max_mapped_pfn; gfn++ ) { @@ -358,6 +356,8 @@ void p2m_teardown(struct p2m_domain *p2m } #endif + p2m_lock(p2m); + p2m->phys_table = pagetable_null(); while ( (pg = page_list_remove_head(&p2m->pages)) )