[PATCH v2] mm/hwpoison: reset hwpoison filter parameters in pfn_inject_exit()

[Miaohe Lin <linmiaohe@huawei.com>]

When hwpoison_inject module is removed, hwpoison_filter_* parameters
should be reset. Otherwise these parameters will have non-default values
at next insmod time.

Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
---
v2:
 Add missing call to reset_hwpoison_filter() per Andrew. Thanks.
---
 mm/hwpoison-inject.c | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/mm/hwpoison-inject.c b/mm/hwpoison-inject.c
index 7ecaa1900137..0b855cd3433a 100644
--- a/mm/hwpoison-inject.c
+++ b/mm/hwpoison-inject.c
@@ -64,10 +64,22 @@ static int hwpoison_unpoison(void *data, u64 val)
 DEFINE_DEBUGFS_ATTRIBUTE(hwpoison_fops, NULL, hwpoison_inject, "%lli\n");
 DEFINE_DEBUGFS_ATTRIBUTE(unpoison_fops, NULL, hwpoison_unpoison, "%lli\n");
 
-static void __exit pfn_inject_exit(void)
+static inline void reset_hwpoison_filter(void)
 {
 	hwpoison_filter_enable = 0;
+	hwpoison_filter_dev_major = ~0U;
+	hwpoison_filter_dev_minor = ~0U;
+	hwpoison_filter_flags_mask = 0;
+	hwpoison_filter_flags_value = 0;
+#ifdef CONFIG_MEMCG
+	hwpoison_filter_memcg = 0;
+#endif
+}
+
+static void __exit pfn_inject_exit(void)
+{
 	debugfs_remove_recursive(hwpoison_dir);
+	reset_hwpoison_filter();
 }
 
 static int __init pfn_inject_init(void)
-- 
2.33.0