[PATCH v4 8/8] mm: Fix exports that inadvertently make put_page() EXPORT_SYMBOL_GPL

From: Dan Williams
Date: Wed Jul 11 2018 - 01:25:20 EST


Now that all producers of dev_pagemap instances in the kernel are
properly converted to EXPORT_SYMBOL_GPL, fix up implicit consumers that
interact with dev_pagemap owners via put_page(). To reiterate,
dev_pagemap producers are EXPORT_SYMBOL_GPL because they adopt and
modify core memory management interfaces such that the dev_pagemap owner
can interact with all other kernel infrastructure and sub-systems
(drivers, filesystems, etc...) that consume page structures.

Fixes: e76384884344 ("mm: introduce MEMORY_DEVICE_FS_DAX and CONFIG_DEV_PAGEMAP_OPS")
Reported-by: Joe Gorse <jhgorse@xxxxxxxxx>
Reported-by: John Hubbard <jhubbard@xxxxxxxxxx>
Tested-by: Joe Gorse <jhgorse@xxxxxxxxx>
Tested-by: John Hubbard <jhubbard@xxxxxxxxxx>
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
---
kernel/memremap.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/memremap.c b/kernel/memremap.c
index 16141b608b63..ecee37b44aa1 100644
--- a/kernel/memremap.c
+++ b/kernel/memremap.c
@@ -330,7 +330,7 @@ EXPORT_SYMBOL_GPL(get_dev_pagemap);

#ifdef CONFIG_DEV_PAGEMAP_OPS
DEFINE_STATIC_KEY_FALSE(devmap_managed_key);
-EXPORT_SYMBOL_GPL(devmap_managed_key);
+EXPORT_SYMBOL(devmap_managed_key);
static atomic_t devmap_enable;

/*
@@ -371,5 +371,5 @@ void __put_devmap_managed_page(struct page *page)
} else if (!count)
__put_page(page);
}
-EXPORT_SYMBOL_GPL(__put_devmap_managed_page);
+EXPORT_SYMBOL(__put_devmap_managed_page);
#endif /* CONFIG_DEV_PAGEMAP_OPS */