powerpc/pseries: Flush lazy kernel mappings after unplug operations

This ensures that the translations for unmapped IO mappings or
unmapped memory are properly removed from the MMU hash table
before such an unplug. Without this, the hypervisor refuses the
unplug operations due to those resources still being mapped by
the partition.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

1 files changed, 7 insertions, 0 deletions

diff --git a/arch/powerpc/platforms/pseries/hotplug-memory.c b/arch/powerpc/platforms/pseries/hotplug-memory.c
index 9b21ee68ea50..01e7b5bb3c1d 100644
--- a/arch/powerpc/platforms/pseries/hotplug-memory.c
+++ b/arch/powerpc/platforms/pseries/hotplug-memory.c
@@ -11,6 +11,7 @@
 
 #include <linux/of.h>
 #include <linux/lmb.h>
+#include <linux/vmalloc.h>
 #include <asm/firmware.h>
 #include <asm/machdep.h>
 #include <asm/pSeries_reconfig.h>
@@ -54,6 +55,12 @@ static int pseries_remove_lmb(unsigned long base, unsigned int lmb_size)
          */
         start = (unsigned long)__va(base);
         ret = remove_section_mapping(start, start + lmb_size);
+
+        /* Ensure all vmalloc mappings are flushed in case they also
+         * hit that section of memory
+         */
+        vm_unmap_aliases();
+
         return ret;
 }