[RFC 01/19] xen/arm: guest_physmap_remove_page: Print a warning if we fail to unmap the page

[Julien Grall <julien.grall@linaro.org>]

The function guest_physmap_remove_page does't have a return value. With
the change "arch/arm: add consistency check to REMOVE p2m changes",
apply_p2m_changes can unlikely fail. Warn the user in this case.

Signed-off-by: Julien Grall <julien.grall@linaro.org>
---
 xen/arch/arm/p2m.c |   14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/xen/arch/arm/p2m.c b/xen/arch/arm/p2m.c
index f93f99a..51f9225 100644
--- a/xen/arch/arm/p2m.c
+++ b/xen/arch/arm/p2m.c
@@ -607,10 +607,16 @@ void guest_physmap_remove_page(struct domain *d,
                                unsigned long gpfn,
                                unsigned long mfn, unsigned int page_order)
 {
-    apply_p2m_changes(d, REMOVE,
-                      pfn_to_paddr(gpfn),
-                      pfn_to_paddr(gpfn + (1<<page_order)),
-                      pfn_to_paddr(mfn), NULL, MATTR_MEM, p2m_invalid);
+    int ret;
+
+    ret = apply_p2m_changes(d, REMOVE,
+                            pfn_to_paddr(gpfn),
+                            pfn_to_paddr(gpfn + (1<<page_order)),
+                            pfn_to_paddr(mfn), NULL, MATTR_MEM, p2m_invalid);
+    if ( ret )
+        dprintk(XENLOG_G_WARNING,
+                "DOM%u: Unable to unmap region GPFN 0x%lx - 0x%lx MFN 0x%lx\n",
+                d->domain_id, gpfn, gpfn + (1 << page_order), mfn);
 }
 
 int p2m_alloc_table(struct domain *d)
-- 
1.7.10.4