From: Juerg Haefliger <juerg.haefli...@hpe.com>

If the page is unmapped by XPFO, a data cache flush results in a fatal
page fault. So don't flush in that case.

Signed-off-by: Juerg Haefliger <juerg.haefli...@canonical.com>
Tested-by: Tycho Andersen <ty...@docker.com>
---
 arch/arm64/mm/flush.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/mm/flush.c b/arch/arm64/mm/flush.c
index 21a8d828cbf4..e17a063b2df2 100644
--- a/arch/arm64/mm/flush.c
+++ b/arch/arm64/mm/flush.c
@@ -20,6 +20,7 @@
 #include <linux/export.h>
 #include <linux/mm.h>
 #include <linux/pagemap.h>
+#include <linux/xpfo.h>
 
 #include <asm/cacheflush.h>
 #include <asm/cache.h>
@@ -30,7 +31,9 @@ void sync_icache_aliases(void *kaddr, unsigned long len)
        unsigned long addr = (unsigned long)kaddr;
 
        if (icache_is_aliasing()) {
-               __clean_dcache_area_pou(kaddr, len);
+               /* Don't flush if the page is unmapped by XPFO */
+               if (!xpfo_page_is_unmapped(virt_to_page(kaddr)))
+                       __clean_dcache_area_pou(kaddr, len);
                __flush_icache_all();
        } else {
                flush_icache_range(addr, addr + len);
-- 
2.11.0


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