• Jason Gunthorpe's avatar
    RDMA/core: Fix incorrect structure packing for booleans · 24104f6a
    Jason Gunthorpe authored
    [ Upstream commit 55efcfcd ]
    
    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.
    
    Cc: stable@vger.kernel.org
    Fixes: 1da177e4 ("Linux-2.6.12-rc2")
    Signed-off-by: default avatarJason Gunthorpe <jgunthorpe@obsidianresearch.com>
    Signed-off-by: default avatarDoug Ledford <dledford@redhat.com>
    Signed-off-by: default avatarSasha Levin <alexander.levin@verizon.com>
    24104f6a
ib_sa.h 15.5 KB