Re: [syzbot] [mm?] kernel BUG in collapse_scan_file

David Hildenbrand (Arm)
2026-03-19T09:21:49Z

On 3/19/26 10:14, Lance Yang wrote:
>
>
> On 2026/3/19 17:00, David Hildenbrand (Arm) wrote:
>> On 3/19/26 09:53, Lorenzo Stoakes (Oracle) wrote:
>>>
>>> Hmm we shouldn't leave this bug in place while working for a fancier
>>> fix??
>>>
>>> Can we get _something_ going as an upstream fix? We can improve
>>> whatever we do
>>> later right?
>>>
>>> David, thoughts?
>>
>> I recall Willy mentioning that the issue is likely a false positive.
>>
>> IIUC, that commit is not upstream? So it only triggers in linux-next.
>
> Right. That does not appear to be in upstream, I only see it in linux-
> next :)
>
>> Which means:
>>
>> 1) If it's a false positive, upstream is not effected (no XA_NODE_BUG_ON)
>>
>> 2) If it's not a false positive, upstream is effected but does not
>> trigger the XA_NODE_BUG_ON
>
> Yep. So this particular BUG_ON is not affecting upstream directly.
>
> That said, syzbot will likely keep hitting it in linux-next and
> generating noise for us until it is addressed there ...

Right, I assume this comes through Willy's tree, so Willy should
consider removing it for the time being.

--
Cheers,

David