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Date:   Fri, 8 Apr 2022 13:31:30 -0300
From:   Jason Gunthorpe <jgg@nvidia.com>
To:     Niels Dossche <dossche.niels@gmail.com>
Cc:     linux-rdma@vger.kernel.org, linux-kernel@vger.kernel.org,
        Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com>,
        Mike Marciniszyn <mike.marciniszyn@cornelisnetworks.com>
Subject: Re: [PATCH] IB/rdmavt: add missing locks in rvt_ruc_loopback
Message-ID: <20220408163130.GA3612543@nvidia.com>
References: <20220228195144.71946-1-dossche.niels@gmail.com>
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On Mon, Feb 28, 2022 at 08:51:44PM +0100, Niels Dossche wrote:
> The documentation of the function rvt_error_qp says both r_lock and
> s_lock need to be held when calling that function.
> It also asserts using lockdep that both of those locks are held.
> rvt_error_qp is called form rvt_send_cq, which is called from
> rvt_qp_complete_swqe, which is called from rvt_send_complete, which is
> called from rvt_ruc_loopback in two places. Both of these places do not
> hold r_lock. Fix this by acquiring a spin_lock of r_lock in both of
> these places.
> The r_lock acquiring cannot be added in rvt_qp_complete_swqe because
> some of its other callers already have r_lock acquired.
> 
> Signed-off-by: Niels Dossche <dossche.niels@gmail.com>
> ---
>  drivers/infiniband/sw/rdmavt/qp.c | 6 +++++-
>  1 file changed, 5 insertions(+), 1 deletion(-)

Applied to for-next, thanks

Jason