1 files changed, 20 insertions, 1 deletions

diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
index 2ab058b0947d..1b734d7a8966 100644
--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -11,6 +11,7 @@
 #include <linux/interrupt.h>
 #include <linux/seq_file.h>
 #include <linux/debugfs.h>
+#include <linux/pfn.h>
 
 #include <asm/e820.h>
 #include <asm/processor.h>
@@ -682,7 +683,7 @@ static int cpa_process_alias(struct cpa_data *cpa)
 {
         struct cpa_data alias_cpa;
         unsigned long laddr = (unsigned long)__va(cpa->pfn << PAGE_SHIFT);
-        unsigned long vaddr;
+        unsigned long vaddr, remapped;
         int ret;
 
         if (cpa->pfn >= max_pfn_mapped)
@@ -737,6 +738,24 @@ static int cpa_process_alias(struct cpa_data *cpa)
         }
 #endif
 
+        /*
+         * If the PMD page was partially used for per-cpu remapping,
+         * the recycled area needs to be split and modified.  Because
+         * the area is always proper subset of a PMD page
+         * cpa->numpages is guaranteed to be 1 for these areas, so
+         * there's no need to loop over and check for further remaps.
+         */
+        remapped = (unsigned long)pcpu_lpage_remapped((void *)laddr);
+        if (remapped) {
+                WARN_ON(cpa->numpages > 1);
+                alias_cpa = *cpa;
+                alias_cpa.vaddr = &remapped;
+                alias_cpa.flags &= ~(CPA_PAGES_ARRAY | CPA_ARRAY);
+                ret = __change_page_attr_set_clr(&alias_cpa, 0);
+                if (ret)
+                        return ret;
+        }
+
         return 0;
 }