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Subject: Re: how to return a chunk of kernel .data to free mem ?
To:     jim.cromie@gmail.com, LKML <linux-kernel@vger.kernel.org>,
        Linux Memory Management List <linux-mm@kvack.org>,
        Jason Baron <jbaron@akamai.com>
References: <CAJfuBxxo5hQLK36J1yL2MV3Zkfdnk=OmGh6Fms1adjB0GWULqA@mail.gmail.com>
From:   David Hildenbrand <david@redhat.com>
Organization: Red Hat
Message-ID: <196e42a7-d50f-48e0-b4bd-e7f3701bfc6d@redhat.com>
Date:   Wed, 9 Jun 2021 13:19:29 +0200
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On 05.06.21 16:50, jim.cromie@gmail.com wrote:
> I have convinced DYNAMIC_DEBUG code to not need
> about 15% of its __dyndbg section, about 30kb on my test kernel.
> 
> This memory is not kmalloc'd, so krealloc wont work.
> (I tried anyway, on a loaded module, it panicd)
> 
> Is there a way to return a chunk of init .data memory to general use ?
> 
> heres the patchset;
> https://lore.kernel.org/lkml/20210529200029.205306-1-jim.cromie@gmail.com/
> 

Hm, you could try free_reserved_page(). But obviously, only full pages 
can be handed to the buddy.

-- 
Thanks,

David / dhildenb