[PATCH 4.19 13/63] s390/mm: Fix clearing storage keys for huge pages

Greg Kroah-Hartman
2024-05-14T11:39:20Z

From: Claudio Imbrenda <imbrenda@linux.ibm.com>

[ Upstream commit 412050af2ea39407fe43324b0be4ab641530ce88 ]

The function __storage_key_init_range() expects the end address to be
the first byte outside the range to be initialized. I.e. end - start
should be the size of the area to be initialized.

The current code works because __storage_key_init_range() will still loop
over every page in the range, but it is slower than using sske_frame().

Fixes: 3afdfca69870 ("s390/mm: Clear skeys for newly mapped huge guest pmds")
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Link: https://lore.kernel.org/r/20240416114220.28489-3-imbrenda@linux.ibm.com
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/s390/mm/hugetlbpage.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/s390/mm/hugetlbpage.c b/arch/s390/mm/hugetlbpage.c
index ff8234bca56cd..6b688e3498c01 100644
--- a/arch/s390/mm/hugetlbpage.c
+++ b/arch/s390/mm/hugetlbpage.c
@@ -146,7 +146,7 @@ static void clear_huge_pte_skeys(struct mm_struct *mm, unsigned long rste)
}

if (!test_and_set_bit(PG_arch_1, &page->flags))
- __storage_key_init_range(paddr, paddr + size - 1);
+ __storage_key_init_range(paddr, paddr + size);
}

void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
--
2.43.0