Re: [patch 2/2] x86, fpu: lazy allocation of FPU area - v3

Pavel Machek
2008-03-06T14:46:30Z

On Tue 2008-03-04 09:55:28, Suresh Siddha wrote:
> On Tue, Mar 04, 2008 at 11:32:20AM +0100, Ingo Molnar wrote:
> >
> > * Suresh Siddha <suresh.b.siddha@intel.com> wrote:
> >
> > > On Mon, Mar 03, 2008 at 08:20:12PM -0500, Christoph Hellwig wrote:
> > > > On Mon, Mar 03, 2008 at 03:02:46PM -0800, Suresh Siddha wrote:
> > > > > + /*
> > > > > + * Memory allocation at the first usage of the FPU and other state.
> > > > > + */
> > > > > + if (!tsk->thread.xstate)
> > > > > + tsk->thread.xstate = kmem_cache_alloc(task_xstate_cachep, GFP_KERNEL);
> > > >
> > > > Also don't we need some kind of error handling here?
> > >
> > > Currently it uses SLAB_PANIC.
> >
> > but SLAB_PANIC only covers kmem_cache_create() failures.
> >
> > kmem_cache_alloc() can fail (return NULL) and not handling it is a bug.
>
> oops. you are correct. Will send a sigsegv in the failure case then. Thanks.

You are introducing possibility of hard to debug error, where previous
code just worked... Does not look like good idea to me.
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