Re: [PATCH 4/4] dmaengine: dmatest: Optionally make test errors fatal

[Tycho Andersen <tycho@kernel.org>]

On Wed, Jul 22, 2026 at 10:47:49AM -0500, Nathan Lynch via B4 Relay wrote:
> From: Nathan Lynch <nathan.lynch@amd.com>
> 
> For automated testing it is useful to have dmatest halt the machine when
> errors occur rather than logging them and continuing, so that the system
> state at the point of failure can be captured instead of allowing the run
> to carry on.
> 
> Add a 'fatal_errors' module parameter, defaulting to 0. When set to a
> non-zero value N, panic the kernel once N test errors have accumulated in
> a run; the count is reset at the start of each run. The panic is triggered
> after the existing result() line is logged, so the specific error (data
> mismatch, mapping/prep/submit error, timeout, or bad completion status) is
> recorded before the crash.
> 
> Assisted-by: Claude:claude-opus-4-8 [Claude-Code]
> Signed-off-by: Nathan Lynch <nathan.lynch@amd.com>

Reviewed-by: Tycho Andersen (AMD) <tycho@kernel.org>

but,

> @@ -583,7 +611,7 @@ static int dmatest_func(void *data)
>  	struct dma_device	*dev;
>  	struct device		*dma_dev;
>  	unsigned int		error_count;
> -	unsigned int		failed_tests = 0;
> +	unsigned int		failed_tests = 0;	/* for this thread */
>  	unsigned int		total_tests = 0;
>  	dma_cookie_t		cookie;
>  	enum dma_status		status;

I would probably drop this hunk if you re-spin. It's on the thread's
stack, so it seems like an "obvious" comment.

Tycho