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

H. Peter Anvin
2008-03-07T12:34:19Z

Pavel Machek wrote:
> On Thu 2008-03-06 16:51:41, Ingo Molnar wrote:
>> * Pavel Machek <pavel@ucw.cz> wrote:
>>
>>>>> 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.
>> hm, how does it differ from any other allocation failure? We could fail
>
> Well, we should not be sending SIGSEGV...? SIGBUS would be cleaner, or
> SIGKILL... what happens when userland tries to catch this one?
>

I'm confused...

Normally when we need memory for userspace and can't get it, we put the
process to sleep until memory is available.

Why is this different in any way?

-hpa