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Date:   Sat, 30 Oct 2021 09:45:54 +0300
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To:     Kishon Vijay Abraham I <kishon@ti.com>,
        Vinod Koul <vkoul@kernel.org>
Cc:     dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org,
        Vignesh Raghavendra <vigneshr@ti.com>
References: <20211029151251.26421-1-kishon@ti.com>
From:   =?UTF-8?Q?P=c3=a9ter_Ujfalusi?= <peter.ujfalusi@gmail.com>
Subject: Re: [PATCH v3 0/2] dmaengine: ti: k3-udma: Fix NULL pointer
 dereference error
In-Reply-To: <20211029151251.26421-1-kishon@ti.com>
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Hi Kishon,

On 29/10/2021 18:12, Kishon Vijay Abraham I wrote:
> NULL pointer de-reference error was observed when all the PCIe endpoint
> functions (22 function in J721E) request a DMA channel. The issue was
> specfically observed when using mem-to-mem copy.
> 
> Changes from v2:
> 1) Fix commit subject and commit log to mention bchan/rchan/tchan to NULL
>    suggested by Peter.

Looks good, however the second patch also fixes the rflow. It is
mentioned in the commit message itself.

I suppose the reason for a split is that the UDMA part
(rchan/tchan/rflow) could be backported as fix for older kernel since
the bchan came later with BCDMA/PKTDMA support?

Can you find a good Fixes tag for these?

> 
> Changes from v1:
> 1) Split the patch for BCDMA and PKTDMA separately
> 2) Fixed the return value of udma_get_rflow() to 0.
> 3) Removed the fixes tag as the patches does not directly apply to the
> commits.
> 
> v1 => https://lore.kernel.org/r/20210209090036.30832-1-kishon@ti.com
> v2 => https://lore.kernel.org/r/20211027055625.11150-1-kishon@ti.com
> 
> Kishon Vijay Abraham I (2):
>   dmaengine: ti: k3-udma: Set bchan to NULL if a channel request fail
>   dmaengine: ti: k3-udma: Set rchan/tchan to NULL if a channel request
>     fail

dmaengine: ti: k3-udma: Set r/tchan or rflow to NULL if request fail

would have bee a better subject line, if you feel you can send an update.

Acked-by: Peter Ujfalusi <peter.ujfalusi@gmail.com>


> 
>  drivers/dma/ti/k3-udma.c | 32 ++++++++++++++++++++++++++------
>  1 file changed, 26 insertions(+), 6 deletions(-)
> 

-- 
Péter