Per GDMA spec, rmb is necessary after checking owner_bits, before reading EQ or CQ entries.

Add rmb in these two places to comply with the specs.

Cc: stable@vger.kernel.org Fixes: ca9c54d2d6a5 ("net: mana: Add a driver for Microsoft Azure Network Adapter (MANA)") Reported-by: Sinan Kaya Sinan.Kaya@microsoft.com Signed-off-by: Haiyang Zhang haiyangz@microsoft.com --- drivers/net/ethernet/microsoft/mana/gdma_main.c | 10 ++++++++++ 1 file changed, 10 insertions(+)

diff --git a/drivers/net/ethernet/microsoft/mana/gdma_main.c b/drivers/net/ethernet/microsoft/mana/gdma_main.c index 5f9240182351..e10b9f8f89e1 100644 --- a/drivers/net/ethernet/microsoft/mana/gdma_main.c +++ b/drivers/net/ethernet/microsoft/mana/gdma_main.c @@ -397,6 +397,11 @@ static void mana_gd_process_eq_events(void *arg) break; }

+ /* Per GDMA spec, rmb is necessary after checking owner_bits, before + * reading eqe. + */ + rmb(); + mana_gd_process_eqe(eq);

eq->head++; @@ -1134,6 +1139,11 @@ static int mana_gd_read_cqe(struct gdma_queue *cq, struct gdma_comp *comp) if (WARN_ON_ONCE(owner_bits != new_bits)) return -1;

+ /* Per GDMA spec, rmb is necessary after checking owner_bits, before + * reading completion info + */ + rmb(); + comp->wq_num = cqe->cqe_info.wq_num; comp->is_sq = cqe->cqe_info.is_sq; memcpy(comp->cqe_data, cqe->cqe_data, GDMA_COMP_DATA_SIZE);