From: Aharon Landau <aharonl@xxxxxxxxxx>
rounddown_pow_of_two is undefined when the input is 0. Therefore we need
to avoid it in ib_umem_find_best_pgsz and return 0.
Otherwise, it could result in incorrect page size.
Fixes: 3361c29e9279 ("RDMA/umem: Use simpler logic for ib_umem_find_best_pgsz()")
Signed-off-by: Aharon Landau <aharonl@xxxxxxxxxx>
Reviewed-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
Reviewed-by: Maor Gottlieb <maorg@xxxxxxxxxxxx>
Signed-off-by: Leon Romanovsky <leonro@xxxxxxxxxx>
---
drivers/infiniband/core/umem.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/infiniband/core/umem.c b/drivers/infiniband/core/umem.c
index 95be8cc75d2e..baaf1bf22941 100644
--- a/drivers/infiniband/core/umem.c
+++ b/drivers/infiniband/core/umem.c
@@ -137,7 +137,7 @@ unsigned long ib_umem_find_best_pgsz(struct ib_umem *umem,
*/
if (mask)
pgsz_bitmap &= GENMASK(count_trailing_zeros(mask), 0);
- return rounddown_pow_of_two(pgsz_bitmap);
+ return pgsz_bitmap ? rounddown_pow_of_two(pgsz_bitmap) : 0;
}
EXPORT_SYMBOL(ib_umem_find_best_pgsz);
--
2.29.2
