Re: [PATCH] __kmalloc: Generate BUG if size requested is too large.

[Dave Hansen <haveblue@us.ibm.com>]

On Thu, 2005-09-22 at 12:32 -0700, Christoph Lameter wrote:
> I had an issue on ia64 where I got a bug in kernel/workqueue because kzalloc
> returned a NULL pointer due to the task structure getting too big for the slab
> allocator. Usually these cases are caught by the kmalloc macro in include/linux/slab.h.
> Compilation will fail if a too big value is passed to kmalloc.

I'd be more concerned that the workqueue code wasn't checking for NULL.
Also, the one place where I see the workqueue code using kzalloc(), it
checks for kzalloc() failure (in __create_workqueue).

> However, kzalloc uses __kmalloc which has no check for that. This
> patch makes __kmalloc bug if a too large entity is requested.

I don't see that in current -git, either.  Which version of the kernel
are you working against?

> void *kzalloc(size_t size, unsigned int __nocast flags)
> {
>         void *ret = kmalloc(size, flags);
>         if (ret)
>                 memset(ret, 0, size);
>         return ret;
> }
> EXPORT_SYMBOL(kzalloc);

-- Dave

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