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Subject: Re: [PATCH] lib/genaloc: Fix allocation of aligned buffer from
 non-aligned chunk
To:     Andrew Morton <akpm@linux-foundation.org>
Cc:     sbates@raithlin.com, logang@deltatee.com, danielmentz@google.com,
        mathieu.desnoyers@efficios.com, linux-kernel@vger.kernel.org,
        labbott@redhat.com
References: <1541506853-10685-1-git-send-email-alexey.skidanov@intel.com>
 <20181106141131.76e94f6b1ff2859d96792aca@linux-foundation.org>
 <d76d64cf-70a9-9c1f-6f11-2d812aacaaef@intel.com>
 <20181107141428.bd1f8b1a989449633394d8c1@linux-foundation.org>
From:   Alexey Skidanov <alexey.skidanov@intel.com>
Message-ID: <7c902049-4fc4-7c13-2ee3-c0a198767359@intel.com>
Date:   Thu, 8 Nov 2018 10:58:20 +0200
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On 11/8/18 00:14, Andrew Morton wrote:
> On Wed, 7 Nov 2018 08:21:07 +0200 Alexey Skidanov <alexey.skidanov@intel.com> wrote:
> 
>>> Why does this need "fixing"?  Are there current callers which can
>>> misalign chunk_start_addr?  Or is there a requirement that future
>>> callers can misalign chunk_start_addr?
>>>
>> I work on adding aligned allocation support for ION heaps
>> (https://www.spinics.net/lists/linux-driver-devel/msg118754.html). Two
>> of these heaps use genpool internally.
>>
>> If you want to have an ability to allocate buffers aligned on different
>> boundaries (for example, 4K, 1MB, ...), this fix actually removes the
>> requirement for chunk_start_addr to be aligned on the max possible
>> alignment.
> 
> OK.  This sort of information should be in the changelog, please.  In
> much detail.
> 
Sure, I'll add this information and resend the patch.

Thanks,
Alexey