[PATCH for-rc 6/6] RDMA/bnxt_re: Fix driver crash on unaligned PSN entry address

[Selvin Xavier <selvin.xavier@broadcom.com>]

From: Naresh Kumar PBS <nareshkumar.pbs@broadcom.com>

When computing the first psn entry, driver checks
for page alignment. If this address is not page aligned,it
attempts to compute the offset in that page for later
use by using ALIGN macro. ALIGN macro does not return offset
bytes but the requested aligned address and hence cannot
be used directly to store as offset.
Since driver was using the address itself instead of offset,
it resulted in invalid address when filling the psn buffer.

Fixed driver to use PAGE_MASK macro to calculate the offset.

Fixes: fddcbbb02af4 ("RDMA/bnxt_re: Simplify obtaining queue entry from hw ring")
Signed-off-by: Naresh Kumar PBS <nareshkumar.pbs@broadcom.com>
Signed-off-by: Selvin Xavier <selvin.xavier@broadcom.com>
---
 drivers/infiniband/hw/bnxt_re/qplib_fp.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/infiniband/hw/bnxt_re/qplib_fp.c b/drivers/infiniband/hw/bnxt_re/qplib_fp.c
index 3535130..9f90cfe 100644
--- a/drivers/infiniband/hw/bnxt_re/qplib_fp.c
+++ b/drivers/infiniband/hw/bnxt_re/qplib_fp.c
@@ -937,10 +937,10 @@ static void bnxt_qplib_init_psn_ptr(struct bnxt_qplib_qp *qp, int size)
 
 	sq = &qp->sq;
 	hwq = &sq->hwq;
+	/* First psn entry */
 	fpsne = (u64)bnxt_qplib_get_qe(hwq, hwq->depth, &psn_pg);
 	if (!IS_ALIGNED(fpsne, PAGE_SIZE))
-		indx_pad = ALIGN(fpsne, PAGE_SIZE) / size;
-
+		indx_pad = (fpsne & ~PAGE_MASK) / size;
 	hwq->pad_pgofft = indx_pad;
 	hwq->pad_pg = (u64 *)psn_pg;
 	hwq->pad_stride = size;
-- 
2.5.5