Re: [PATCH] mm: page_alloc: avoid false page outside zone error info

[Miaohe Lin]

On 2023/7/4 20:13, Matthew Wilcox wrote:
> On Tue, Jul 04, 2023 at 07:18:23PM +0800, Miaohe Lin wrote:
>> @@ -470,6 +470,8 @@ static int page_outside_zone_boundaries(struct zone *zone, struct page *page)
>>  		sp = zone->spanned_pages;
>>  		if (!zone_spans_pfn(zone, pfn))
>>  			ret = 1;
>> +		else
>> +			ret = 0;
> 
> Surely 'ret = zone_spans_pfn(zone, pfn);' ?

Do you mean 'ret = !zone_spans_pfn(zone, pfn);'?  This format looks fine to me.

> 
> Also, did you spot this by inspection or do you have a test-case or bug
> report?  Should this have a Fixes: tag?

This is from code inspection. The race window should be really small thus hard to trigger
in real world. And yes, it seems Fixes tag is a really ancient commit:

	Fixes: bdc8cb984576 ("[PATCH] memory hotplug locking: zone span seqlock")

Thanks for your comment and reply.