Re: [PATCH 2/4 v4] kernel/fork.c: avoid division by zero

From: Ingo Molnar
Date: Tue Feb 24 2015 - 02:35:59 EST



* Heinrich Schuchardt <xypron.glpk@xxxxxx> wrote:

> PAGE_SIZE is not guaranteed to be equal to or less than 8 times the
> THREAD_SIZE.
>
> E.g. architecture hexagon may have page size 1M and thread size 4096.
> This would lead to a division by zero in the calculation of max_threads.
>
> With 32-bit calculus there is no solution which delivers valid results
> for all possible combinations of the parameters.
> The code is only called once.
> Hence a 64-bit calculation can be used as solution.
>
> The calculation of max_threads is moved to a separate function.

Please keep the 'move to a separate function' patch in a
separate patch and don't mix it up with the fix, as I
suggested it in my previous review.

Thanks,

Ingo
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