Re: [PATCH v2 0/6] gfs2: Fix mmap + page fault deadlocks

From: Al Viro
Date: Mon Jul 19 2021 - 16:47:19 EST


On Mon, Jul 19, 2021 at 12:39:26AM +0200, Andreas Gruenbacher wrote:
> Hi Linus et al.,
>
> here's an update to the gfs2 mmap + page faults fix that implements
> Linus's suggestion of disabling page faults while we're holding the
> inode glock.
>
> This passes fstests except for test generic/095, which fails due to an
> independent bug in the iov_iter code. I'm currently trying to get
> initial feedback from Al and Christoph on that.
>
> Any feedback would be welcome.

What tree is that against? Because in mainline your #5 sure as hell
won't apply...

There uio.h has
enum iter_type {
/* iter types */
ITER_IOVEC,
ITER_KVEC,
ITER_BVEC,
ITER_PIPE,
ITER_XARRAY,
ITER_DISCARD,
};

and your series assumes

enum iter_type {
/* iter types */
ITER_IOVEC = 4,
ITER_KVEC = 8,
ITER_BVEC = 16,
ITER_PIPE = 32,
ITER_DISCARD = 64,
};

What had that been tested with?