On 09-02-23, 21:37, Eric Pilmore wrote:
> From: Eric Pilmore <epilmore@xxxxxxxxxx>
>
> Resolves a panic that can occur on AMD systems, typically during host
> shutdown, after the PTDMA driver had been exercised. The issue was
> the pt_issue_pending() function is mistakenly assuming that there will
> be at least one descriptor in the Submitted queue when the function
> is called. However, it is possible that both the Submitted and Issued
> queues could be empty, which could result in pt_cmd_callback() being
> mistakenly called with a NULL pointer.
> Ref: Bugzilla Bug 216856.
>
> Fixes: 6fa7e0e836e2 ("dmaengine: ptdma: fix concurrency issue with
> multiple dma transfer")
This should not be split two two lines!
> Signed-off-by: Eric Pilmore <epilmore@xxxxxxxxxx>
> ---
> drivers/dma/ptdma/ptdma-dmaengine.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/dma/ptdma/ptdma-dmaengine.c
> b/drivers/dma/ptdma/ptdma-dmaengine.c
> index cc22d162ce25..1aa65e5de0f3 100644
> --- a/drivers/dma/ptdma/ptdma-dmaengine.c
> +++ b/drivers/dma/ptdma/ptdma-dmaengine.c
> @@ -254,7 +254,7 @@ static void pt_issue_pending(struct dma_chan *dma_chan)
> spin_unlock_irqrestore(&chan->vc.lock, flags);
>
> /* If there was nothing active, start processing */
> - if (engine_is_idle)
> + if (engine_is_idle && desc)
Please run checkpatch before sending patches
WARNING: please, no spaces at the start of a line
#40: FILE: drivers/dma/ptdma/ptdma-dmaengine.c:257:
+ if (engine_is_idle && desc)$
WARNING: suspect code indent for conditional statements (7, 15)
#40: FILE: drivers/dma/ptdma/ptdma-dmaengine.c:257:
+ if (engine_is_idle && desc)
pt_cmd_callback(desc, 0);
> pt_cmd_callback(desc, 0);
> }
>
> --
> 2.38.1
--
~Vinod
