Re: [PATCH 3.9-table] NTB: Link toggle memory leak

[Jon Mason <jon.mason@intel.com>]

On Sat, May 18, 2013 at 11:44:51AM +0900, Jonghwan Choi wrote:
> From: Jon Mason <jon.mason@intel.com>
> 
> This patch looks like it should be in the 3.9-stable tree, should we apply
> it?

Yes, thanks.

> 
> ------------------
> 
> From: "Jon Mason <jon.mason@intel.com>"
> 
> commit b77b2637b39ecc380bb08992380d7d48452b0872 upstream
> 
> Each link-up will allocate a new NTB receive buffer when the NTB
> properties are negotiated with the remote system.  These allocations did
> not check for existing buffers and thus did not free them.  Now, the
> driver will check for an existing buffer and free it if not of the
> correct size, before trying to alloc a new one.
> 
> Cc: <stable@vger.kernel.org> # 3.9.x: ad3e2751: ntb: off by one
> Cc: <stable@vger.kernel.org> # 3.9.x: cc0f868d: NTB: fix pointer math
> Cc: <stable@vger.kernel.org> # 3.9.x: 113fc505: NTB: Handle 64bit BAR
> Signed-off-by: Jon Mason <jon.mason@intel.com>
> Signed-off-by: Jonghwan Choi <jhbird.choi@samsung.com>
> ---
>  drivers/ntb/ntb_transport.c | 32 ++++++++++++++++++++------------
>  1 file changed, 20 insertions(+), 12 deletions(-)
> 
> diff --git a/drivers/ntb/ntb_transport.c b/drivers/ntb/ntb_transport.c
> index 2258649..f5a424d 100644
> --- a/drivers/ntb/ntb_transport.c
> +++ b/drivers/ntb/ntb_transport.c
> @@ -507,17 +507,37 @@ static void ntb_transport_setup_qp_mw(struct ntb_transport *nt,
>  	qp->tx_pkts = 0;
>  }
>  
> +static void ntb_free_mw(struct ntb_transport *nt, int num_mw)
> +{
> +	struct ntb_transport_mw *mw = &nt->mw[num_mw];
> +	struct pci_dev *pdev = ntb_query_pdev(nt->ndev);
> +
> +	if (!mw->virt_addr)
> +		return;
> +
> +	dma_free_coherent(&pdev->dev, mw->size, mw->virt_addr, mw->dma_addr);
> +	mw->virt_addr = NULL;
> +}
> +
>  static int ntb_set_mw(struct ntb_transport *nt, int num_mw, unsigned int size)
>  {
>  	struct ntb_transport_mw *mw = &nt->mw[num_mw];
>  	struct pci_dev *pdev = ntb_query_pdev(nt->ndev);
>  
> +	/* No need to re-setup */
> +	if (mw->size == ALIGN(size, 4096))
> +		return 0;
> +
> +	if (mw->size != 0)
> +		ntb_free_mw(nt, num_mw);
> +
>  	/* Alloc memory for receiving data.  Must be 4k aligned */
>  	mw->size = ALIGN(size, 4096);
>  
>  	mw->virt_addr = dma_alloc_coherent(&pdev->dev, mw->size, &mw->dma_addr,
>  					   GFP_KERNEL);
>  	if (!mw->virt_addr) {
> +		mw->size = 0;
>  		dev_err(&pdev->dev, "Unable to allocate MW buffer of size %d\n",
>  		       (int) mw->size);
>  		return -ENOMEM;
> @@ -529,18 +549,6 @@ static int ntb_set_mw(struct ntb_transport *nt, int num_mw, unsigned int size)
>  	return 0;
>  }
>  
> -static void ntb_free_mw(struct ntb_transport *nt, int num_mw)
> -{
> -	struct ntb_transport_mw *mw = &nt->mw[num_mw];
> -	struct pci_dev *pdev = ntb_query_pdev(nt->ndev);
> -
> -	if (!mw->virt_addr)
> -		return;
> -
> -	dma_free_coherent(&pdev->dev, mw->size, mw->virt_addr, mw->dma_addr);
> -	mw->virt_addr = NULL;
> -}
> -
>  static void ntb_qp_link_cleanup(struct work_struct *work)
>  {
>  	struct ntb_transport_qp *qp = container_of(work,
> -- 
> 1.8.1.2
>