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    SubjectRe: [RFC] situation with fput() locking (was Re: [PULL REQUEST] : ima-appraisal patches)
    On Fri, Apr 20, 2012 at 12:58 PM, Al Viro <viro@zeniv.linux.org.uk> wrote:
    >
    > So does a bunch of other places.  Let me dig out the call graph circa
    > 3.3.0...  Here is the relevant part:

    Yes, but a lot of those would actually be helped by a helper function
    that does all of:
    - grab mmap_sem
    - call do_m[un]map()
    - release mmap_sem

    and that would actually clean them up even in the current case.

    And then we could do the cleanup in just the helper function.

    Not all, no. But a preparatory patch that just creates the helper
    functions for doing brk/mmap/munmap would get rid of a fairly big
    chunk of them.

    You can visualize how many of them do that by just doing

    git grep -5 do_m[un]*map

    and then high-lghting '_write(' (to visually show the
    down_write/up_write pairs that surround most of them) by searching for
    it.

    Are they all like that? No. But most of the ones outside of mm/ do fit
    that simple pattern and should probably be fixed up just to have them
    not contain VM locking details in them *anyway*.

    Linus
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