The i386 ABI disagrees with most other ABIs regarding alignment of
data type larger than 4 bytes: on most ABIs a padding must be added at
end of the structures, while it is not required on i386.
So for most ABIs struct mlx5_ib_create_srq gets implicitly padded to be
aligned on a 8 bytes multiple, while for i386, such padding is not
added.
Tool pahole could be used to find such implicit padding:
$ pahole --anon_include \
--nested_anon_include \
--recursive \
--class_name mlx5_ib_create_srq \
drivers/infiniband/hw/mlx5/mlx5_ib.o
Then, structure layout can be compared between i386 and x86_64:
+++ obj-i386/drivers/infiniband/hw/mlx5/mlx5_ib.o.pahole.txt 2014-03-28 11:43:07.386413682 +0100
--- obj-x86_64/drivers/infiniband/hw/mlx5/mlx5_ib.o.pahole.txt 2014-03-27 13:06:17.788472721 +0100
@@ -69,7 +68,6 @@ struct mlx5_ib_create_srq {
__u64 db_addr; /* 8 8 */
__u32 flags; /* 16 4 */
- /* size: 20, cachelines: 1, members: 3 */
- /* last cacheline: 20 bytes */
+ /* size: 24, cachelines: 1, members: 3 */
+ /* padding: 4 */
+ /* last cacheline: 24 bytes */
};
ABI disagreement will make an x86_64 kernel try to read past
the buffer provided by an i386 binary.
When boundary check will be implemented, the x86_64 kernel will
refuse to read past the i386 userspace provided buffer and the
uverb will fail.
Anyway, if the structure lay in memory on a page boundary and
next page is not mapped, ib_copy_from_udata() will fail and the
uverb will fail.
This patch makes create_srq_user() takes care of the input
data size to handle the case where no padding was provided.
This way, x86_64 kernel will be able to handle struct mlx5_ib_create_srq
as sent by unpatched and patched i386 libmlx5.
Link: http://marc.info/?i=cover.1399309513.git.ydroneaud@opteya.com
Cc: <stable@vger.kernel.org>
Fixes: e126ba97db ("mlx5: Add driver for Mellanox Connect-IB adapter")
Signed-off-by: Yann Droneaud <ydroneaud@opteya.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
The i386 ABI disagrees with most other ABIs regarding alignment of
data type larger than 4 bytes: on most ABIs a padding must be added at
end of the structures, while it is not required on i386.
So for most ABI struct mlx5_ib_create_cq get padded to be aligned on a
8 bytes multiple, while for i386, such padding is not added.
The tool pahole can be used to find such implicit padding:
$ pahole --anon_include \
--nested_anon_include \
--recursive \
--class_name mlx5_ib_create_cq \
drivers/infiniband/hw/mlx5/mlx5_ib.o
Then, structure layout can be compared between i386 and x86_64:
+++ obj-i386/drivers/infiniband/hw/mlx5/mlx5_ib.o.pahole.txt 2014-03-28 11:43:07.386413682 +0100
--- obj-x86_64/drivers/infiniband/hw/mlx5/mlx5_ib.o.pahole.txt 2014-03-27 13:06:17.788472721 +0100
@@ -34,9 +34,8 @@ struct mlx5_ib_create_cq {
__u64 db_addr; /* 8 8 */
__u32 cqe_size; /* 16 4 */
- /* size: 20, cachelines: 1, members: 3 */
- /* last cacheline: 20 bytes */
+ /* size: 24, cachelines: 1, members: 3 */
+ /* padding: 4 */
+ /* last cacheline: 24 bytes */
};
This ABI disagreement will make an x86_64 kernel try to read past the
buffer provided by an i386 binary.
When boundary check will be implemented, a x86_64 kernel will refuse
to read past the i386 userspace provided buffer and the uverb will
fail.
Anyway, if the structure lies in memory on a page boundary and next
page is not mapped, ib_copy_from_udata() will fail when trying to read
the 4 bytes of padding and the uverb will fail.
This patch makes create_cq_user() takes care of the input data size to
handle the case where no padding is provided.
This way, x86_64 kernel will be able to handle struct
mlx5_ib_create_cq as sent by unpatched and patched i386 libmlx5.
Link: http://marc.info/?i=cover.1399309513.git.ydroneaud@opteya.com
Cc: <stable@vger.kernel.org>
Fixes: e126ba97db ("mlx5: Add driver for Mellanox Connect-IB adapter")
Signed-off-by: Yann Droneaud <ydroneaud@opteya.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
Commit c1be5232d2 ("Fix micro UAR allocator") broke binary compatibility
between libmlx5 and mlx5_ib since it defines a different value to the number
of micro UARs per page, leading to wrong calculation in libmlx5. This patch
defines struct mlx5_ib_alloc_ucontext_req_v2 as an extension to struct
mlx5_ib_alloc_ucontext_req. The extended size is determined in mlx5_ib_alloc_ucontext()
and in case of old library we use uuarn 0 which works fine -- this is
acheived due to create_user_qp() falling back from high to medium then to
low class where low class will return 0. For new libraries we use the
more sophisticated allocation algorithm.
Signed-off-by: Eli Cohen <eli@mellanox.com>
Reviewed-by: Yann Droneaud <ydroneaud@opteya.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
Implement resize CQ which is a mandatory verb in mlx5.
Signed-off-by: Eli Cohen <eli@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
The driver is comprised of two kernel modules: mlx5_ib and mlx5_core.
This partitioning resembles what we have for mlx4, except that mlx5_ib
is the pci device driver and not mlx5_core.
mlx5_core is essentially a library that provides general functionality
that is intended to be used by other Mellanox devices that will be
introduced in the future. mlx5_ib has a similar role as any hardware
device under drivers/infiniband/hw.
Signed-off-by: Eli Cohen <eli@mellanox.com>
Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
[ Merge in coccinelle fixes from Fengguang Wu <fengguang.wu@intel.com>.
- Roland ]
Signed-off-by: Roland Dreier <roland@purestorage.com>
