Re: [PATCH] lib/genaloc: Fix allocation of aligned buffer from non-aligned chunk

From: Andrew Morton
Date: Wed Nov 07 2018 - 17:14:32 EST


On Wed, 7 Nov 2018 08:21:07 +0200 Alexey Skidanov <alexey.skidanov@xxxxxxxxx> 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.