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Date:   Mon, 5 Sep 2022 16:16:49 -0700
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To:     Jens Axboe <axboe@kernel.dk>,
        Andrew Morton <akpm@linux-foundation.org>,
        Logan Gunthorpe <logang@deltatee.com>,
        Dan Williams <dan.j.williams@intel.com>,
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        linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org
From:   John Hubbard <jhubbard@nvidia.com>
Subject: New topic branch for block + gup work?
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Hi Jens,

After you suggested a topic branch [1] as a way to address the recent
bio_map_user_iov() conflict in linux-next, I've reviewed a few more
patchsets in mm, and am now starting to suspect that a topic branch
would be ideal here.

Logan's "Userspace P2PDMA with O_DIRECT NVMe devices" series [2], my
"convert most filesystems to pin_user_pages_fast()" series [3], and the
block layer change from [1], all conflict in iov_iter*, and in
bio_map_user_iov().

Less of an issue but still worth considering, Dan's "Fix the DAX-gup
mistake" series [4] conflicts in gup.c, too.

Maybe:

    gup_bio

, or something like that, as a topic branch?

Everyone: thoughts, preferences here?


[1] https://lore.kernel.org/r/20220901161722.739d2013@canb.auug.org.au

[2] https://lore.kernel.org/r/20220825152425.6296-1-logang@deltatee.com

[3] https://lore.kernel.org/r/20220831041843.973026-1-jhubbard@nvidia.com

[4] https://lore.kernel.org/r/166225775968.2351842.11156458342486082012.stgit@dwillia2-xfh.jf.intel.com


thanks,

-- 
John Hubbard
NVIDIA