Re: [PATCH RESEND 1/2] RDMA/mlx5: Fix number of allocated XLT entries

[Jason Gunthorpe]

On Wed, Sep 08, 2021 at 10:18:48AM +0200, Niklas Schnelle wrote:
> In commit 8010d74b9965b ("RDMA/mlx5: Split the WR setup out of
> mlx5_ib_update_xlt()") the allocation logic was split out of
> mlx5_ib_update_xlt() and the logic was changed to enable better OOM
> handling. Sadly this change introduced a miscalculation of the number of
> entries that were actually allocated when under memory pressure where it
> can actually become 0 which on s390 lets dma_map_single() fail.
> 
> It can also lead to corruption of the free pages list when the wrong
> number of entries is used in the calculation of sg->length which is used
> as argument for free_pages().
> 
> Fix this by using the allocation size instead of misusing
> get_order(size).
> 
> Cc: stable@xxxxxxxxxxxxxxx
> Fixes: 8010d74b9965b ("RDMA/mlx5: Split the WR setup out of mlx5_ib_update_xlt()")
> Signed-off-by: Niklas Schnelle <schnelle@xxxxxxxxxxxxx>
> ---
>  drivers/infiniband/hw/mlx5/mr.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

Both patches applied to for-rc, thanks

Jason