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SubjectRe: Hopefully, kmalloc() will always succeed, but if it doesn't then....
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 >         struct mixart_enum_connector_resp *connector;
> struct mixart_audio_info_req *audio_info_req;
> struct mixart_audio_info_resp *audio_info;
>
> connector = kmalloc(sizeof(*connector), GFP_KERNEL);
> audio_info_req = kmalloc(sizeof(*audio_info_req), GFP_KERNEL);
> audio_info = kmalloc(sizeof(*audio_info), GFP_KERNEL);
> if (! connector || ! audio_info_req || ! audio_info) {
> err = -ENOMEM;
> goto __error;
> }

This is not a bug. All of the pointers are initialized, and if
kmalloc() fails, then one of them will be set to NULL. However,
kfree(NULL) is a perfectly fine thing to do (kfree just returns
immediately in this case).

So this is just a way of saving some tests and optimizing for the
common case when all allocations succeed. In other words, this is
good code -- although the spacing is slightly bogus: it should be

if (!connector || !audio_info_req || !audio_info) {

and also using __error as a label is slightly silly -- why not just
make it "error"?

- R.
-
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