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.chu@xxxxxxxxxx> Signed-off-by: Joao Martins <joao.m.martins@xxxxxxxxxx> Reviewed-by: Naoya Horiguchi <naoya.horiguchi@xxxxxxx> Reviewed-by: Dan Williams <dan.j.williams@xxxxxxxxx> Reviewed-by: Muchun Song <songmuchun@xxxxxxxxxxxxx> --- mm/memory-failure.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 8f0ee5b08696..f5749db8fad3 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -1600,6 +1600,12 @@ 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 -- 2.17.2
