Re: [PATCH] RDMA/rxe: Fix parameter errors

[Jason Gunthorpe <jgg@nvidia.com>]

On Thu, Jan 19, 2023 at 12:05:07PM -0600, Bob Pearson wrote:
> Correct errors in rxe_param.h caused by extending the range of
> indices for MRs allowing it to overlap the range for MWs. Since
> the driver determines whether an rkey is for an MR or MW by comparing
> the index part of the rkey with these ranges this can cause an
> MR to be incorrectly determined to be an MW.
> 
> Additionally the parameters which determine the size of the index
> ranges for MR, MW, QP and SRQ are incorrect since the actual
> number of integers in the range [min, max] is (max - min + 1) not
> (max - min).
> 
> This patch corrects these errors.
> 
> Fixes: 0994a1bcd5f7 ("RDMA/rxe: Bump up default maximum values used via uverbs")
> Signed-off-by: Bob Pearson <rpearsonhpe@gmail.com>
> ---
>  drivers/infiniband/sw/rxe/rxe_param.h | 27 +++++++++++++++++++--------
>  1 file changed, 19 insertions(+), 8 deletions(-)

This

commit 1aefe5c177c1922119afb4ee443ddd6ac3140b37
Author: Daisuke Matsuda <matsuda-daisuke@fujitsu.com>
Date:   Tue Dec 20 17:08:48 2022 +0900

    RDMA/rxe: Prevent faulty rkey generation
    
    If you create MRs more than 0x10000 times after loading the module,
    responder starts to reply NAKs for RDMA/Atomic operations because of rkey
    violation detected in check_rkey(). The root cause is that rkeys are
    incremented each time a new MR is created and the value overflows into the
    range reserved for MWs.
    
    This commit also increases the value of RXE_MAX_MW that has been limited
    unlike other parameters.
    
    Fixes: 0994a1bcd5f7 ("RDMA/rxe: Bump up default maximum values used via uverbs")
    Link: https://lore.kernel.org/r/20221220080848.253785-2-matsuda-daisuke@fujitsu.com
    Signed-off-by: Daisuke Matsuda <matsuda-daisuke@fujitsu.com>
    Tested-by: Li Zhijian <lizhijian@fujitsu.com>
    Reviewed-by: Li Zhijian <lizhijian@fujitsu.com>
    Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>


Is already in v6.2-rc and conflicts with this patch, it looks like it
is doing the same thing, can you sort it out please?

Thanks,
Jason