Re: [PATCH v2] EFI loader: remove redundant code

From: Eugene Korenevsky
Date: Wed Nov 02 2016 - 09:56:12 EST


> > *e820ext is always NULL in 'alloc_e820ext()' (see the code of 'exit_boot()').
> > Without loss of generality we can replace freeing with returning
> > EFI_INVALID_PARAMETER. So if the caller would ever incorrectly pass non-NULL
> > *e820ext, he will obtain a returned error code.
> >
>
> What exactly are you trying to fix here? Adding new artificial failure
> modes is hardly worth it when all you are doing is cleaning up code
> that by itself is correct to begin with, but is simply never called.

This code (free_pool, assignments) is dead whether it is correct or
not. So it is to be removed.
The check gives some assurance that memory is not leaked if the calling
code is changed.


> > @@ -956,11 +956,8 @@ static efi_status_t alloc_e820ext(u32 nr_desc, struct setup_data **e820ext,
> > size = sizeof(struct setup_data) +
> > sizeof(struct e820entry) * nr_desc;
> >
> > - if (*e820ext) {
> > - efi_call_early(free_pool, *e820ext);
> > - *e820ext = NULL;
> > - *e820ext_size = 0;
> > - }
> > + if (*e820ext)
> > + return EFI_INVALID_PARAMETER;
> >
> > status = efi_call_early(allocate_pool, EFI_LOADER_DATA,
> > size, (void **)e820ext);
> > --


--
Eugene