memory_failure_dev_pagemap() at the moment assumes base pages (e.g.
dax_lock_page()). For devmap with compound pages fetch the
compound_head in case a tail page memory failure is being handled.
Currently this is a nop, but in the advent of compound pages in
dev_pagemap it allows memory_failure_dev_pagemap() to keep working.
Reported-by: Jane Chu <jane....@oracle.com>
Signed-off-by: Joao Martins <joao.m.mart...@oracle.com>
Reviewed-by: Naoya Horiguchi <naoya.horigu...@nec.com>
Reviewed-by: Dan Williams <dan.j.willi...@intel.com>
Reviewed-by: Muchun Song <songmuc...@bytedance.com>
---
mm/memory-failure.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index 60df8fcd0444..beee19a5aa0f 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -1538,6 +1538,12 @@ static int memory_failure_dev_pagemap(unsigned long pfn,
int flags,
goto out;
}
+ /*
+ * Pages instantiated by device-dax (not filesystem-dax)
+ * may be compound pages.
+ */
+ page = compound_head(page);
+
/*
* Prevent the inode from being freed while we are interrogating
* the address_space, typically this would be handled by
--
2.17.1
