4.4-stable review patch. If anyone has any objections, please let me know.
------------------ From: Logan Gunthorpe <[email protected]> [ Upstream commit cbd27448faff4843ac4b66cc71445a10623ff48d ] When using the max_mw_size parameter of ntb_transport to limit the size of the Memory windows, communication cannot be established and the queues freeze. This is because the mw_size that's reported to the peer is correctly limited but the size used locally is not. So the MW is initialized with a buffer smaller than the window but the TX side is using the full window. This means the TX side will be writing to a region of the window that points nowhere. This is easily fixed by applying the same limit to tx_size in ntb_transport_init_queue(). Fixes: e26a5843f7f5 ("NTB: Split ntb_hw_intel and ntb_transport drivers") Signed-off-by: Logan Gunthorpe <[email protected]> Acked-by: Allen Hubbe <[email protected]> Cc: Dave Jiang <[email protected]> Signed-off-by: Jon Mason <[email protected]> Signed-off-by: Sasha Levin <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/ntb/ntb_transport.c | 3 +++ 1 file changed, 3 insertions(+) --- a/drivers/ntb/ntb_transport.c +++ b/drivers/ntb/ntb_transport.c @@ -955,6 +955,9 @@ static int ntb_transport_init_queue(stru mw_base = nt->mw_vec[mw_num].phys_addr; mw_size = nt->mw_vec[mw_num].phys_size; + if (max_mw_size && mw_size > max_mw_size) + mw_size = max_mw_size; + tx_size = (unsigned int)mw_size / num_qps_mw; qp_offset = tx_size * (qp_num / mw_count);
