RDMA/core: Fix incorrect structure packing for booleans
authorJason Gunthorpe <jgunthorpe@obsidianresearch.com>
Fri, 23 Dec 2016 01:07:52 +0000 (18:07 -0700)
committerWilly Tarreau <w@1wt.eu>
Wed, 7 Jun 2017 22:47:02 +0000 (00:47 +0200)
commite9a1e1cc1cd1a7f684a938eff41caf2cdff615d2
treeef7a0a3b285b830a3c24642425ad791675c0a884
parent5beea85761cade8086b1420d788257eb3c5aac50
RDMA/core: Fix incorrect structure packing for booleans

commit 55efcfcd7776165b294f8b5cd6e05ca00ec89b7c upstream.

The RDMA core uses ib_pack() to convert from unpacked CPU structs
to on-the-wire bitpacked structs.

This process requires that 1 bit fields are declared as u8 in the
unpacked struct, otherwise the packing process does not read the
value properly and the packed result is wired to 0. Several
places wrongly used int.

Crucially this means the kernel has never, set reversible
correctly in the path record request. It has always asked for
irreversible paths even if the ULP requests otherwise.

When the kernel is used with a SM that supports this feature, it
completely breaks communication management if reversible paths are
not properly requested.

The only reason this ever worked is because opensm ignores the
reversible bit.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
include/rdma/ib_sa.h