From mboxrd@z Thu Jan 1 00:00:00 1970 From: Julien Grall Subject: Re: [V6 PATCH 6/7] pvh dom0: Add and remove foreign pages Date: Mon, 09 Dec 2013 02:45:19 +0000 Message-ID: <52A52EBF.4080704@linaro.org> References: <1386297524-15483-1-git-send-email-mukesh.rathor@oracle.com> <1386297524-15483-7-git-send-email-mukesh.rathor@oracle.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1386297524-15483-7-git-send-email-mukesh.rathor@oracle.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Mukesh Rathor , Xen-devel@lists.xensource.com Cc: george.dunlap@eu.citrix.com, keir.xen@gmail.com, tim@xen.org, Ian Campbell , JBeulich@suse.com List-Id: xen-devel@lists.xenproject.org On 12/06/2013 02:38 AM, Mukesh Rathor wrote: > In this patch, a new function, xenmem_add_foreign_to_p2m(), is added > to map pages from foreign guest into current dom0 for domU creation. > Such pages are typed p2m_map_foreign. Also, support is added here to > XENMEM_remove_from_physmap to remove such pages. Note, in the remove > path, we must release the refcount that was taken during the map phase. > > Signed-off-by: Mukesh Rathor > --- > xen/arch/x86/mm.c | 88 +++++++++++++++++++++++++++++++++++++++++---- > xen/common/memory.c | 37 ++++++++++++++++++- > xen/include/asm-arm/p2m.h | 2 + > 3 files changed, 118 insertions(+), 9 deletions(-) This patch doesn't compile on ARM: memory.c: In function 'do_memory_op': memory.c:682:20: error: unused variable 'p2mt' [-Werror=unused-variable] cc1: all warnings being treated as errors For x86, when a domain is destroyed and there is still some foreign page mapped, you forget to decrease the refcount (via put_page). It will likely result to a zombie domain. For instance a stubdomain with foreign map on a guest. If the stubdomain doesn't release the page, this guest will become a zombie. -- Julien Grall