Re: [Kernel Bug] WARNING in mempool_alloc_noprof

[Vlastimil Babka]

On 2/3/26 17:27, Christoph Hellwig wrote:
> On Tue, Feb 03, 2026 at 06:52:39PM +0900, Harry Yoo wrote:
>> Maybe the changelog could be rephrased a bit,
>> but overall LGTM, thanks!
> 
> 
> No, that does not make sense.  If mempool is used with __GFP_RECLAIM in
> the flags it won't fail, and if it isn't, GFP_NOFAIL can't work.

So that means as long as there's __GFP_RECLAIM, __GFP_NOFAIL isn't wrong,
just redundant.

> So if there is any work in mempool_alloc it's that it should warn about
> GFP_NOFAIL.  The fix is in the callers to not pass the flag, assuming
> current kernels still do this.

We could just tolerate the redundant. The code would be simpler too. But I
don't feel too strongly about it.