From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andres Lagar-Cavilla Subject: [PATCH 1 of 3] x86/mem_sharing: Don't destroy a page's shared state before depleting its tuple list Date: Tue, 24 Apr 2012 15:48:21 -0400 Message-ID: <796b523346ac55f93897.1335296901@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.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: xen-devel@lists.xen.org Cc: andres@gridcentric.ca, tim@xen.org List-Id: xen-devel@lists.xenproject.org xen/arch/x86/mm/mem_sharing.c | 8 +++++--- 1 files changed, 5 insertions(+), 3 deletions(-) Signed-off-by: Andres Lagar-Cavilla diff -r 08946bbc8036 -r 796b523346ac xen/arch/x86/mm/mem_sharing.c --- a/xen/arch/x86/mm/mem_sharing.c +++ b/xen/arch/x86/mm/mem_sharing.c @@ -963,7 +963,9 @@ gfn_found: last_gfn = list_has_one_entry(&page->sharing->gfns); if ( last_gfn ) { - /* Clean up shared state */ + /* Clean up shared state. Get rid of the tuple + * before destroying the rmap. */ + mem_sharing_gfn_destroy(d, gfn_info); audit_del_list(page); page->sharing = NULL; atomic_dec(&nr_shared_mfns); @@ -974,7 +976,8 @@ gfn_found: * (possibly freeing the page), and exit early */ if ( flags & MEM_SHARING_DESTROY_GFN ) { - mem_sharing_gfn_destroy(d, gfn_info); + if ( !last_gfn ) + mem_sharing_gfn_destroy(d, gfn_info); put_page_and_type(page); mem_sharing_page_unlock(page); if ( last_gfn && @@ -987,7 +990,6 @@ gfn_found: if ( last_gfn ) { - mem_sharing_gfn_destroy(d, gfn_info); /* Making a page private atomically unlocks it */ BUG_ON(page_make_private(d, page) != 0); goto private_page_found;