Re: [PATCH v3 1/1] khugepaged: fix readahead lock inversion in collapse_file()

[David Hildenbrand (Arm)]

On 10/18/26 04:47, Baolin Wang wrote:
> 
> 
> On 10/17/26 3:41 PM, Lance Yang wrote:
>>
>>
>> On 2026/10/17 13:43, Baolin Wang wrote:
>>>
>>>
>>>
>>> OK.
>>>
>>>
>>> Sounds good.
>>>
>>>
>>> But why not add RA logic in collapse_pmd(), as we do for
>>> SCAN_PAGE_DIRTY_OR_WRITEBACK? There's already retry logic there, and this
>>> would also simplify the long collapse_file().
>>
>> That would be cleaner, yeah. Some older stable trees don't have that
>> outer retry loop, though ... I'd prefer to get the fix backported first,
>> then move the RA/retry logic out in a follow-up, wdyt?
> 
> IIRC, the approach to bug fixes is to fix bugs properly and cleanly for
> upstream, without being constrained by backporting requirements.
> 
> Anyway, I don't have a strong opinion on this. Let's also see what David prefers.

Let's get this fixed in a acceptable way in a reasonable timeframe; it's been
broken for too long. ... and follow up with bigger cleanups later.

@Lance is this version good to review for that purpose or are you planning a resend?

-- 
Cheers,

David