Hi Sagi-
> On Oct 6, 2015, at 5:48 AM, Sagi Grimberg <[email protected]> wrote: > > There is no need to require LOCAL_DMA_LKEY support in order to > use fast registration as the PD allocation makes sure that there > is a local_dma_lkey. In other words, all devices now have a local DMA lkey, so the check is unnecessary. > This caused a NULL pointer dereference in mlx5 which removed > the support for LOCAL_DMA_LKEY. Where was the bad dereference? in mlx5, or in xprtrdma? > Fixes: bb6c96d72879 ("xprtrdma: Replace global lkey with lkey local to PD") > Signed-off-by: Sagi Grimberg <[email protected]> > --- > net/sunrpc/xprtrdma/verbs.c | 7 ++----- > 1 files changed, 2 insertions(+), 5 deletions(-) > > diff --git a/net/sunrpc/xprtrdma/verbs.c b/net/sunrpc/xprtrdma/verbs.c > index eb081ad..7efd9ef 100644 > --- a/net/sunrpc/xprtrdma/verbs.c > +++ b/net/sunrpc/xprtrdma/verbs.c > @@ -543,11 +543,8 @@ rpcrdma_ia_open(struct rpcrdma_xprt *xprt, struct > sockaddr *addr, int memreg) > } > > if (memreg == RPCRDMA_FRMR) { > - /* Requires both frmr reg and local dma lkey */ > - if (((devattr->device_cap_flags & > - (IB_DEVICE_MEM_MGT_EXTENSIONS|IB_DEVICE_LOCAL_DMA_LKEY)) != > - (IB_DEVICE_MEM_MGT_EXTENSIONS|IB_DEVICE_LOCAL_DMA_LKEY)) || > - (devattr->max_fast_reg_page_list_len == 0)) { > + if (!(devattr->device_cap_flags & IB_DEVICE_MEM_MGT_EXTENSIONS) > || > + (devattr->max_fast_reg_page_list_len == 0)) { > dprintk("RPC: %s: FRMR registration " > "not supported by HCA\n", __func__); > memreg = RPCRDMA_MTHCAFMR; Reviewed-by: Chuck Lever <[email protected]> — Chuck Lever -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
