mm/hwpoison: avoid the impact of hwpoison_filter() return value on mce handler

When the hwpoison page meets the filter conditions, it should not be
regarded as successful memory_failure() processing for mce handler, but
should return a distinct value, otherwise mce handler regards the error
page has been identified and isolated, which may lead to calling
set_mce_nospec() to change page attribute, etc.

Here memory_failure() return -EOPNOTSUPP to indicate that the error
event is filtered, mce handler should not take any action for this
situation and hwpoison injector should treat as correct.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: luofei <[email protected]>
Acked-by: Borislav Petkov <[email protected]>
Cc: Dave Hansen <[email protected]>
Cc: H. Peter Anvin <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Miaohe Lin <[email protected]>
Cc: Naoya Horiguchi <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Tony Luck <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

1 files changed, 2 insertions, 0 deletions

diff --git a/drivers/base/memory.c b/drivers/base/memory.c
index 365cd4a7f239..abf407e45467 100644
--- a/drivers/base/memory.c
+++ b/drivers/base/memory.c
@@ -555,6 +555,8 @@ static ssize_t hard_offline_page_store(struct device *dev,
 		return -EINVAL;
 	pfn >>= PAGE_SHIFT;
 	ret = memory_failure(pfn, 0);
+	if (ret == -EOPNOTSUPP)
+		ret = 0;
 	return ret ? ret : count;
 }