Re: [PATCH] slab: prevent warnings when allocating with __GFP_NOWARN

Sasha Levin
2013-06-11T16:20:00Z

On 06/11/2013 12:13 PM, Eric Dumazet wrote:
> On Tue, 2013-06-11 at 11:44 -0400, Sasha Levin wrote:
>> On 06/11/2013 11:23 AM, Christoph Lameter wrote:
>>> On Tue, 11 Jun 2013, Pekka Enberg wrote:
>>>
>>>> So you're OK with going forward with Sasha's patch? It's needed
>>>> because __GFP_NOWARN was specifically added there to fix this
>>>> issue earlier.
>>>
>>> Why dont we fix the call site to use vmalloc instead for larger allocs?
>>>
>>
>> We should probably be doing both.
>
> Allowing a pipe to store thousands of page refs seems quite useless and
> dangerous.

It might be, but you need CAP_SYS_RESOURCE to go into the dangerous
zone (>pipe_max_size).

So if root (or someone with that cap) wants to go there, as Rusty says:
"Root asked, we do."

Thanks,
Sasha