Re: Ugly rmap NULL ptr deref oopsie on hibernate (was Linux 2.6.34-rc3)

[Rik van Riel]

On 04/06/2010 08:10 PM, Linus Torvalds wrote:

> That said, the code that _really_ confuses me is the stuff that uses
> "anon_vma_clone()". Could you please also explain the code flow of
> vma_adjust() to mere mortals, please?

That's easier said than done.  I spent 3 days with pen and paper,
going over that code before I made the anon_vma changes, first
verifying that the code is indeed correct and then figuring out
how I could make the anon_vma changes safely.

I am not happy with the complexity of the code around vma_adjust,
but could not find a way to simplify it and still keep merging
VMAs the way we do.

My largest change to vma_adjust was moving some code closer to
the beginning of the function, so I could bail out if the
allocation failed, without making change to the vma...

> I suspect Borislav is sleeping. But at least we have a patch for him to
> test when he wakes up ;)

I am looking forward to the test results.

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/