Re: [PATCH mm-unstable v1 04/20] mm: add early FAULT_FLAG_UNSHARE consistency checks

[Vlastimil Babka]

On 11/16/22 11:26, David Hildenbrand wrote:
> For now, FAULT_FLAG_UNSHARE only applies to anonymous pages, which
> implies a COW mapping. Let's hide FAULT_FLAG_UNSHARE early if we're not
> dealing with a COW mapping, such that we treat it like a read fault as
> documented and don't have to worry about the flag throughout all fault
> handlers.
> 
> While at it, centralize the check for mutual exclusion of
> FAULT_FLAG_UNSHARE and FAULT_FLAG_WRITE and just drop the check that
> either flag is set in the WP handler.
> 
> Signed-off-by: David Hildenbrand <david@xxxxxxxxxx>
> ---
>  mm/huge_memory.c |  3 ---
>  mm/hugetlb.c     |  5 -----
>  mm/memory.c      | 23 ++++++++++++++++++++---
>  3 files changed, 20 insertions(+), 11 deletions(-)

Reviewed-by: Vlastimil Babka <vbabka@xxxxxxx>