lkml.org 
[lkml]   [2023]   [Nov]   [3]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    From
    Date
    SubjectRe: [PATCH RFC V2 1/6] RDMA/rxe: RDMA/rxe: don't allow registering !PAGE_SIZE mr
    On Fri, Nov 3, 2023 at 5:56 PM Li Zhijian <lizhijian@fujitsu.com> wrote:
    >
    > rxe_set_page() only store one PAGE_SIZE page by the step of page_size.
    > when page_size != PAGE_SIZE, we cannot restore the address with wrong
    > index and page_offset.
    >
    > Let's take a look how current the xarray is being used.
    >
    > 0. offset = iova & (page_size -1); // offset is less than page_size
    > but may not PAGE_SIZE
    > 1. index = (iova - mr.iova) >> page_shift;
    > 2. page = xa_load(&mr->page_list, index);
    > 3. page_va = kmap_local_page(page) // map one page only, that means only
    > memory [page_va, page_va + PAGE_SIZE)
    > is valid for this mapping.
    > 4. memcpy(addr, page_va + offset, bytes);
    >
    > - when page_size > PAGE_SIZE, the offset could be beyond PAGE_SIZE,
    > then page_va + offset may be invalid.
    > - when page_size < PAGE_SIZE, the offset may get lost.
    >
    > Note that this patch will break some ULPs that try to register 4K
    > MR when PAGE_SIZE is not 4K. SRP and nvme over RXE is known to be
    > impacted.
    >
    > Signed-off-by: Li Zhijian <lizhijian@fujitsu.com>
    >
    > ---
    > ---
    > drivers/infiniband/sw/rxe/rxe_mr.c | 6 ++++++
    > 1 file changed, 6 insertions(+)
    >
    > diff --git a/drivers/infiniband/sw/rxe/rxe_mr.c b/drivers/infiniband/sw/rxe/rxe_mr.c
    > index f54042e9aeb2..3755e530e6dc 100644
    > --- a/drivers/infiniband/sw/rxe/rxe_mr.c
    > +++ b/drivers/infiniband/sw/rxe/rxe_mr.c
    > @@ -234,6 +234,12 @@ int rxe_map_mr_sg(struct ib_mr *ibmr, struct scatterlist *sgl,
    > struct rxe_mr *mr = to_rmr(ibmr);
    > unsigned int page_size = mr_page_size(mr);
    >
    > + if (page_size != PAGE_SIZE) {
    > + rxe_err_mr(mr, "Unsupport mr page size %x, expect PAGE_SIZE(%lx)\n",
    > + page_size, PAGE_SIZE);
    > + return -EINVAL;
    > + }

    Are you kidding us? What problem you are fixing? Do you make tests in your host?

    A rubbish patch.

    > +
    > mr->nbuf = 0;
    > mr->page_shift = ilog2(page_size);
    > mr->page_mask = ~((u64)page_size - 1);
    > --
    > 2.41.0
    >

    \
     
     \ /
      Last update: 2023-11-20 13:47    [W:5.774 / U:1.076 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site