>
> On Fri, Oct 23, 2020 at 09:47:59AM +0200, Laurent Cremmer wrote:
> > The third instance spotted by manual examination.
>
> It is friday, I might be overlooking something obvious, so bear with me.
>
> > In static long region_add(...) and static long region_cgh(...) , releasing
> > the acquired lock when exiting via their error path was removed.
> > This will cause these functions to return with a lock held if they do not
> > succeed.
>
> If they do not suceed, it means that allocate_file_region_entries returned
> non-zero, which means that we hit:
>
> spin_unlock(&resv->lock);
> for (i = 0; i < to_allocate; i++) {
> trg = kmalloc(sizeof(*trg), GFP_KERNEL);
> if (!trg)
> goto out_of_memory;
> list_add(&trg->link, &allocated_regions);
> }
>
> So, we do spin_unlock before jumping to out_of_memory.
>
> > A a new function allocate_file_region_entries was also introduced that
> > must be called with a lock held and returned with the lock held.
> > However the lock is temporarily released during processing but will not
> > be reacquired on error.
>
> As stated above, region_add/region_chr exit immediately on allocate_file_region_entries
> failure, so it does not need to acquire the lock.
>
I came to the same conclusion with the help of David's remarks :-) .
And in the end, this patch would be more about fixing the readability
of the code than fixing a live problem per-se. If it ain't broken,
don't fix it as they say :-)
It is friday, so thanks for taking the time to look into this.
>
> --
> Oscar Salvador
> SUSE L3
