Re: [PATCH v2 12/13] mm: Move __alloc_pages() to mm/internal.h

[Brendan Jackman]

On Tue Jun 23, 2026 at 6:50 AM UTC, Hao Ge wrote:
> Hi Brendan
>
>
> On 2026/6/22 19:14, Brendan Jackman wrote:
>> On Mon Jun 22, 2026 at 10:21 AM UTC, sashiko-bot wrote:
>>> Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
>>> - [Low] Missing EXPORT_SYMBOL for out-of-line alloc_pages_node_noprof() causes widespread module linker errors.
>>> --
>>>
>>> commit 42f7742177beb0066c00a7aa081250feb5859171
>>> Author: Brendan Jackman <jackmanb@xxxxxxxxxx>
>>>
>>> mm: Move __alloc_pages() to mm/internal.h
>>>
>>> This commit moves the __alloc_pages() family of internal functions to
>>> mm/internal.h to restrict them to the mm subsystem. It also moves
>>> alloc_pages_node_noprof() out-of-line into mm/page_alloc.c since it
>>> depends on __alloc_pages_noprof().
>>>
>>>> diff --git a/mm/page_alloc.c b/mm/page_alloc.c
>>>> index 36f0d625a4390..38238203ef7b0 100644
>>>> --- a/mm/page_alloc.c
>>>> +++ b/mm/page_alloc.c
>>> [ ... ]
>>>
>>>> @@ -5419,6 +5419,17 @@ struct page *__alloc_pages_noprof(gfp_t gfp, unsigned int order,
>>>>   }
>>>>   EXPORT_SYMBOL(__alloc_pages_noprof);
>>> [Severity: Low]
>>> Since __alloc_pages_noprof() is no longer visible outside of mm/, should this
>>> EXPORT_SYMBOL be removed?
>> Yep.
>>
>>>> +struct page *alloc_pages_node_noprof(int nid, gfp_t gfp_mask, unsigned int order)
>>>> +{
>>>> +	if (nid == NUMA_NO_NODE)
>>>> +		nid = numa_mem_id();
>>>> +
>>>> +	VM_BUG_ON(nid < 0 || nid >= MAX_NUMNODES);
>>>> +	warn_if_node_offline(nid, gfp_mask);
>>>> +
>>>> +	return __alloc_pages_noprof(gfp_mask, order, nid, NULL);
>>>> +}
>>> [Severity: Low]
>>> Does this code cause module linker errors? alloc_pages_node_noprof() is called
>>> by the alloc_pages_node() macro in include/linux/gfp.h, but it does not have
>>> an EXPORT_SYMBOL.
>> Yep. Doesn't show up in defconfig but if you set CONFIG_BLK_DEV_UBLK=m
>> then:
>>
>> ERROR: modpost: "alloc_pages_node_noprof" [drivers/block/ublk_drv.ko] undefined!
>
> I was about to report this linker issue myself, but Sashiko caught it first.
>
> While testing your patch on top of mm-new, I hit the exact same modpost
>
> undefined symbol error as mentioned above:
>
>    MODPOST Module.symvers
> ERROR: modpost: "alloc_pages_node_noprof" [arch/x86/kvm/kvm-intel.ko] 
> undefined!
> ERROR: modpost: "alloc_pages_node_noprof" [arch/x86/kvm/kvm-amd.ko] 
> undefined!
> ERROR: modpost: "alloc_pages_node_noprof" [drivers/gpu/drm/ttm/ttm.ko] 
> undefined!
> ERROR: modpost: "alloc_pages_node_noprof" [drivers/misc/sgi-xp/xpc.ko] 
> undefined!
> ERROR: modpost: "alloc_pages_node_noprof" [drivers/misc/sgi-gru/gru.ko] 
> undefined!
> ERROR: modpost: "alloc_pages_node_noprof" 
> [drivers/net/ethernet/amazon/ena/ena.ko] undefined!
> ERROR: modpost: "alloc_pages_node_noprof" 
> [drivers/net/ethernet/amd/xgbe/amd-xgbe.ko] undefined!
> ERROR: modpost: "alloc_pages_node_noprof" 
> [drivers/net/ethernet/aquantia/atlantic/atlantic.ko] undefined!
> ERROR: modpost: "alloc_pages_node_noprof" 
> [drivers/net/ethernet/chelsio/cxgb4/cxgb4.ko] undefined!
> ERROR: modpost: "alloc_pages_node_noprof" 
> [drivers/net/ethernet/chelsio/cxgb4vf/cxgb4vf.ko] undefined!
> WARNING: modpost: suppressed 14 unresolved symbol warnings because there 
> were too many)

FWIW something like this happened on a previous patchset of mine, and
someone was like "so you just sent patches without any testing huh?" so
I just wanna note: I did test this (see cover letter for details) I just
don't bother with modules!

Anyway, this is the 2nd time I've sent a patch that breaks the build of
CONFIG_KVM_INTEL=m so I guess it's time to add a new build to my test
scripts :)