IB/qib: Fix a possible data corruption when receiving packets
Prevent a receive data corruption by ensuring that the write to update
the rcvhdrheadn register to generate an interrupt is at the very end
of the receive processing.
Signed-off-by: Ramkrishna Vepa <ram.vepa@qlogic.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@qlogic.com>
Cc: <stable@kernel.org>
Signed-off-by: Roland Dreier <roland@purestorage.com>
diff --git a/drivers/infiniband/hw/qib/qib_iba6120.c b/drivers/infiniband/hw/qib/qib_iba6120.c
index 781a802..4f18e2d 100644
--- a/drivers/infiniband/hw/qib/qib_iba6120.c
+++ b/drivers/infiniband/hw/qib/qib_iba6120.c
@@ -2076,9 +2076,11 @@
static void qib_update_6120_usrhead(struct qib_ctxtdata *rcd, u64 hd,
u32 updegr, u32 egrhd, u32 npkts)
{
- qib_write_ureg(rcd->dd, ur_rcvhdrhead, hd, rcd->ctxt);
if (updegr)
qib_write_ureg(rcd->dd, ur_rcvegrindexhead, egrhd, rcd->ctxt);
+ mmiowb();
+ qib_write_ureg(rcd->dd, ur_rcvhdrhead, hd, rcd->ctxt);
+ mmiowb();
}
static u32 qib_6120_hdrqempty(struct qib_ctxtdata *rcd)