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Date: Wed, 1 Jun 2016 09:51:51 -0400
From: Mike Snitzer <snitzer@redhat.com>
To: Christoph Hellwig <hch@infradead.org>
Cc: Ming Lei <ming.lei@canonical.com>, Jens Axboe <axboe@fb.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
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Subject: Re: [PATCH v6 0/8] block: prepare for multipage bvecs
Message-ID: <20160601135150.GA30759@redhat.com>
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On Wed, Jun 01 2016 at  9:44am -0400,
Christoph Hellwig <hch@infradead.org> wrote:

> On Wed, Jun 01, 2016 at 08:38:41PM +0800, Ming Lei wrote:
> > > be dm-crypt.c.  Maybe you've identified some indirect use of
> > > BIO_MAX_SIZE?
> > 
> > I mean the recently introduced BIO_MAX_SIZE in -next tree:
> > 
> > https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git/commit/drivers/md/dm-crypt.c?id=4ed89c97b0706477b822ea2182827640c0cec486
> 
> The crazy bcache bios striking back once again.  I really think it's
> harmful having a _MAX value and then having a minor driver
> reinterpreting it and sending larger ones.  Until we can lift the
> maximum limit in general nad have common code exercise it we really need
> to stop bcache from sending these instead of littering the tree with
> workarounds.

So should I not push this type of fix to Linus now?  I was going to send
the above commit and this one to him this week:
https://git.kernel.org/cgit/linux/kernel/git/device-mapper/linux-dm.git/commit/?h=dm-4.7&id=57b3001b240629ecc5266d28c845e23ca5f11719

Instead, should bcache be made to not do what it is doing?