From 49fa63d8c2f95b636cc31a7164aeac0309dfa3c9 Mon Sep 17 00:00:00 2001 From: Steve Wise Date: Wed, 22 Jul 2015 14:14:17 -0500 Subject: [PATCH] RDMA/cxgb3: fail get_dma_mr on 64 bit arches T3 HW only supports 32 bit MRs. If the system uses 64 bit memory addresses, then a registered 32 bit MR will wrap and write to the wrong memory when used with addresses > 4GB. To prevent this, simply fail to allocate an MR on 64 bit machines (other means of registering memory are still available and software can still work, we just don't allow this means of memory registration). Signed-off-by: Steve Wise Signed-off-by: Doug Ledford --- drivers/infiniband/hw/cxgb3/iwch_provider.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/infiniband/hw/cxgb3/iwch_provider.c b/drivers/infiniband/hw/cxgb3/iwch_provider.c index b1b73232f217..bbbe0184e592 100644 --- a/drivers/infiniband/hw/cxgb3/iwch_provider.c +++ b/drivers/infiniband/hw/cxgb3/iwch_provider.c @@ -736,6 +736,10 @@ static struct ib_mr *iwch_get_dma_mr(struct ib_pd *pd, int acc) /* * T3 only supports 32 bits of size. */ + if (sizeof(phys_addr_t) > 4) { + pr_warn_once(MOD "Cannot support dma_mrs on this platform.\n"); + return ERR_PTR(-ENOTSUPP); + } bl.size = 0xffffffff; bl.addr = 0; kva = 0; -- 2.20.1