[PATCH v4] IB/core: Fix unaligned accesses

David Ahern
2015-05-03T13:48:26Z

Addresses the following kernel logs seen during boot of sparc systems:

Kernel unaligned access at TPC[103bce50] cm_find_listen+0x34/0xf8 [ib_cm]
Kernel unaligned access at TPC[103bce50] cm_find_listen+0x34/0xf8 [ib_cm]
Kernel unaligned access at TPC[103bce50] cm_find_listen+0x34/0xf8 [ib_cm]
Kernel unaligned access at TPC[103bce50] cm_find_listen+0x34/0xf8 [ib_cm]
Kernel unaligned access at TPC[103bce50] cm_find_listen+0x34/0xf8 [ib_cm]

Signed-off-by: David Ahern <david.ahern-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org>
---
v4
- fix uses of IB_CM_COMPARE_SIZE in memcmp noticed by Shachar

v3
- updated definition of IB_CM_COMPARE_SIZE to account for u32 walking
per Yann's comment
- added const to src/mask args to cm_mask_copy and removed extra whitespace
per Bart's comments
- changed 2 private_data declarations to u32 as suggested by Jason

v2
- updated per Jason's comments

drivers/infiniband/core/cm.c | 23 +++++++++++------------
drivers/infiniband/core/cm_msgs.h | 4 ++--
include/rdma/ib_cm.h | 7 ++++---
3 files changed, 17 insertions(+), 17 deletions(-)

diff --git a/drivers/infiniband/core/cm.c b/drivers/infiniband/core/cm.c
index e28a494e2a3a..0c1419105ff0 100644
--- a/drivers/infiniband/core/cm.c
+++ b/drivers/infiniband/core/cm.c
@@ -437,39 +437,38 @@ static struct cm_id_private * cm_acquire_id(__be32 local_id, __be32 remote_id)
return cm_id_priv;
}

-static void cm_mask_copy(u8 *dst, u8 *src, u8 *mask)
+static void cm_mask_copy(u32 *dst, const u32 *src, const u32 *mask)
{
int i;

- for (i = 0; i < IB_CM_COMPARE_SIZE / sizeof(unsigned long); i++)
- ((unsigned long *) dst)[i] = ((unsigned long *) src)[i] &
- ((unsigned long *) mask)[i];
+ for (i = 0; i < IB_CM_COMPARE_SIZE; i++)
+ dst[i] = src[i] & mask[i];
}

static int cm_compare_data(struct ib_cm_compare_data *src_data,
struct ib_cm_compare_data *dst_data)
{
- u8 src[IB_CM_COMPARE_SIZE];
- u8 dst[IB_CM_COMPARE_SIZE];
+ u32 src[IB_CM_COMPARE_SIZE];
+ u32 dst[IB_CM_COMPARE_SIZE];

if (!src_data || !dst_data)
return 0;

cm_mask_copy(src, src_data->data, dst_data->mask);
cm_mask_copy(dst, dst_data->data, src_data->mask);
- return memcmp(src, dst, IB_CM_COMPARE_SIZE);
+ return memcmp(src, dst, sizeof(src));
}

-static int cm_compare_private_data(u8 *private_data,
+static int cm_compare_private_data(u32 *private_data,
struct ib_cm_compare_data *dst_data)
{
- u8 src[IB_CM_COMPARE_SIZE];
+ u32 src[IB_CM_COMPARE_SIZE];

if (!dst_data)
return 0;

cm_mask_copy(src, private_data, dst_data->mask);
- return memcmp(src, dst_data->data, IB_CM_COMPARE_SIZE);
+ return memcmp(src, dst_data->data, sizeof(src));
}

/*
@@ -538,7 +537,7 @@ static struct cm_id_private * cm_insert_listen(struct cm_id_private *cm_id_priv)

static struct cm_id_private * cm_find_listen(struct ib_device *device,
__be64 service_id,
- u8 *private_data)
+ u32 *private_data)
{
struct rb_node *node = cm.listen_service_table.rb_node;
struct cm_id_private *cm_id_priv;
@@ -953,7 +952,7 @@ int ib_cm_listen(struct ib_cm_id *cm_id, __be64 service_id, __be64 service_mask,
cm_mask_copy(cm_id_priv->compare_data->data,
compare_data->data, compare_data->mask);
memcpy(cm_id_priv->compare_data->mask, compare_data->mask,
- IB_CM_COMPARE_SIZE);
+ sizeof(compare_data->mask));
}

cm_id->state = IB_CM_LISTEN;
diff --git a/drivers/infiniband/core/cm_msgs.h b/drivers/infiniband/core/cm_msgs.h
index be068f47e47e..8b76f0ef965e 100644
--- a/drivers/infiniband/core/cm_msgs.h
+++ b/drivers/infiniband/core/cm_msgs.h
@@ -103,7 +103,7 @@ struct cm_req_msg {
/* local ACK timeout:5, rsvd:3 */
u8 alt_offset139;

- u8 private_data[IB_CM_REQ_PRIVATE_DATA_SIZE];
+ u32 private_data[IB_CM_REQ_PRIVATE_DATA_SIZE / sizeof(u32)];

} __attribute__ ((packed));

@@ -801,7 +801,7 @@ struct cm_sidr_req_msg {
__be16 rsvd;
__be64 service_id;

- u8 private_data[IB_CM_SIDR_REQ_PRIVATE_DATA_SIZE];
+ u32 private_data[IB_CM_SIDR_REQ_PRIVATE_DATA_SIZE / sizeof(u32)];
} __attribute__ ((packed));

struct cm_sidr_rep_msg {
diff --git a/include/rdma/ib_cm.h b/include/rdma/ib_cm.h
index 0e3ff30647d5..39ed2d2fbd51 100644
--- a/include/rdma/ib_cm.h
+++ b/include/rdma/ib_cm.h
@@ -105,7 +105,8 @@ enum ib_cm_data_size {
IB_CM_SIDR_REQ_PRIVATE_DATA_SIZE = 216,
IB_CM_SIDR_REP_PRIVATE_DATA_SIZE = 136,
IB_CM_SIDR_REP_INFO_LENGTH = 72,
- IB_CM_COMPARE_SIZE = 64
+ /* compare done u32 at a time */
+ IB_CM_COMPARE_SIZE = (64 / sizeof(u32))
};

struct ib_cm_id;
@@ -337,8 +338,8 @@ void ib_destroy_cm_id(struct ib_cm_id *cm_id);
#define IB_SDP_SERVICE_ID_MASK cpu_to_be64(0xFFFFFFFFFFFF0000ULL)

struct ib_cm_compare_data {
- u8 data[IB_CM_COMPARE_SIZE];
- u8 mask[IB_CM_COMPARE_SIZE];
+ u32 data[IB_CM_COMPARE_SIZE];
+ u32 mask[IB_CM_COMPARE_SIZE];
};

/**
--
2.3.0