[PATCH 4.6 010/203] IB/core: Fix bit curruption in ib_device_cap_flags structure

Greg Kroah-Hartman
2016-07-25T21:31:04Z

From: Max Gurtovoy <maxg@mellanox.com>

commit 47355b3cd7d3c9c5226bff7c449b9d269fb17fa6 upstream.

ib_device_cap_flags 64-bit expansion caused caps overlapping
and made consumers read wrong device capabilities. For example
IB_DEVICE_SG_GAPS_REG was falsely read by the iser driver causing
it to use a non-existing capability. This happened because signed
int becomes sign extended when converted it to u64. Fix this by
casting IB_DEVICE_ON_DEMAND_PAGING enumeration to ULL.

Fixes: f5aa9159a418 ('IB/core: Add arbitrary sg_list support')
Reported-by: Robert LeBlanc <robert@leblancnet.us>
Acked-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Matan Barak <matanb@mellanox.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
include/rdma/ib_verbs.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/include/rdma/ib_verbs.h
+++ b/include/rdma/ib_verbs.h
@@ -217,7 +217,7 @@ enum ib_device_cap_flags {
IB_DEVICE_CROSS_CHANNEL = (1 << 27),
IB_DEVICE_MANAGED_FLOW_STEERING = (1 << 29),
IB_DEVICE_SIGNATURE_HANDOVER = (1 << 30),
- IB_DEVICE_ON_DEMAND_PAGING = (1 << 31),
+ IB_DEVICE_ON_DEMAND_PAGING = (1ULL << 31),
IB_DEVICE_SG_GAPS_REG = (1ULL << 32),
IB_DEVICE_VIRTUAL_FUNCTION = ((u64)1 << 33),
};