Re: [PATCH mm-hotfixes] mm/rmap: clear vma->anon_vma on error

[David Hildenbrand (Arm)]

On 3/18/26 14:03, Lorenzo Stoakes (Oracle) wrote:
> On Wed, Mar 18, 2026 at 01:52:44PM +0100, David Hildenbrand (Arm) wrote:
>>
>> Acked-by: David Hildenbrand (Arm) <david@xxxxxxxxxx>
>>
> 
> Thanks!
> 
>> LGTM. I was wondering whether anon_vma_clone() should take care of
>> setting up dst->anon_vma. It looks a bit odd in dup_anon_vma.
> 
> Well in the fork case we don't want to set vma->anon_vma, as we use
> vma->anon_vma to denote whether or not we reused another anon_vma. For
> split + remap, we already duplicated it via vm_area_dup() ->
> vm_area_init_from().
> 
> But... now we have enum vma_operation threaded through here, we can just do
> that there like:
> 
> 	/* dst is unfaulted, so inherit src's anon_vma. */
> 	if (operation == VMA_OP_MERGE_UNFAULTED)
> 		dst->anon_vma = src->anon_vma;
> 

Exactly what I had in mind.

-- 
Cheers,

David