On Thu, Dec 16, 2021 at 11:24:36PM +0800, Greg KH wrote:

Did you run the kernel before your change and then after your change to
ensure that the failure you saw before your change is now properly
fixed?

How did you test this?

Thank you for your answer. But I haven't run it yet.
And in fact I don't know how to trigger the alloc failure.
I just find the other place like eni_init_one() in `drivers/atm/eni.c`
check the return value of the dma_alloc_coherent().
So that's possible to alloc failure.
Therefore, in order to avoid the dereference of the null pointer, it might
be better to deal with it.

Sincerely thanks,

jiasheng jiang