From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andres Lagar-Cavilla Subject: [PATCH 2 of 6] Fix handling of m2p map in set_shared_p2m_entry Date: Mon, 14 Nov 2011 16:48:43 -0500 Message-ID: <1ef55d87b4590ff9a8cc.1321307323@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, George.Dunlap@eu.citrix.com, andres@gridcentric.ca, tim@xen.org, keir.xen@gmail.com, adin@gridcentric.ca List-Id: xen-devel@lists.xenproject.org xen/arch/x86/mm/p2m.c | 5 +++-- 1 files changed, 3 insertions(+), 2 deletions(-) When updating a p2m mapping to shared, previous code unconditionally set the m2p entry for the old mfn to invalid. We now check that the old mfn does not remain shared. Signed-off-by: Andres Lagar-Cavilla diff -r d9a344a5c1e3 -r 1ef55d87b459 xen/arch/x86/mm/p2m.c --- a/xen/arch/x86/mm/p2m.c +++ b/xen/arch/x86/mm/p2m.c @@ -714,8 +714,9 @@ set_shared_p2m_entry(struct domain *d, u * sharable first */ ASSERT(p2m_is_shared(ot)); ASSERT(mfn_valid(omfn)); - /* XXX: M2P translations have to be handled properly for shared pages */ - set_gpfn_from_mfn(mfn_x(omfn), INVALID_M2P_ENTRY); + if ( ((mfn_to_page(omfn)->u.inuse.type_info & PGT_type_mask) + != PGT_shared_page) ) + set_gpfn_from_mfn(mfn_x(omfn), INVALID_M2P_ENTRY); P2M_DEBUG("set shared %lx %lx\n", gfn, mfn_x(mfn)); rc = set_p2m_entry(p2m, gfn, mfn, PAGE_ORDER_4K, p2m_ram_shared, p2m->default_access);