[PATCH] global: the _bh variety of rcu helpers have been unified
Bruno Wolff III
bruno at wolff.to
Sat Mar 16 17:11:11 CET 2019
On Thu, Mar 14, 2019 at 23:14:39 -0600,
"Jason A. Donenfeld" <Jason at zx2c4.com> wrote:
>Based on your research, how does the below strike you? It's certainly
>not pretty, but I'm struggling to come up with a better solution.
I think anything that doesn't try to keep the _bh versions around is going to
be ugly. But keeping the _bh versions is not going to be acceptible upstream,
so that doesn't seem to be an option. What you did looks pretty good
given the constraints.
In the talk I saw, the motivation for the change was that mismatching
rcu functions caused security issues, though I don't know how practical
it is to exploit those mistakes. So I worry a bit about breaking things
in old kernels accidentally, in the future. I don't have any good ideas for
automatically catching misuse in new code.
I did try the version you committed, yesterday, and it seemed to work
fine on a 5.1 kernel.
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