[Drbd-dev] Re: bio clone must copy io_vec

[Philipp Reisner <philipp.reisner@linbit.com>]

Hi all,

I am reffering to Jens' fix for md...

> The way md uses bio_clones, it's possible for the original bio to be freed
> before the clone is freed. This means the clone ->bi_io_vec points to freed
> memory potentially. Fix it by duplicating the io_vec as well.
[...]

In DRBD the thing is different. 
We use __bio_clone() but we will never end IO for our original bio before 
we have not finished IO for our cloned BIO.

My fist thought was to have a own copy of __bio_clone() in place, which
behaves like the __bio_clone() of Linux-2.6.10-vanilla.

But on the other hand I think I can convert it over to use bio_clone()
within a few hours. Well I will give it a try, and let you know if
I end up with a patch...

PS: Jens, when I am the owner of a BIO I can do with the private
    member what ever I want, right ?
    And I am the owner of a bio clones with bio_clone() right ?

-Philipp
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