Re: [PATCH v3] mm/page_vma_mapped_walk: Use ptep_get_lockless() for lockless access

[Alexander Gordeev]

On Thu, May 28, 2026 at 04:14:03PM +0200, Oscar Salvador (SUSE) wrote:
> On Thu, May 28, 2026 at 12:24:35PM +0100, Lorenzo Stoakes wrote:
> > On Thu, May 28, 2026 at 09:55:07AM +0200, Alexander Gordeev wrote:
> > > Switch from ptep_get() to ptep_get_lockless() accessor for
> > > PTE reads when no lock is taken.
> > 
> > This is an insufficient commit message that's just saying what you're doing,
> > which isn't very useful.
> > 
> > Please explain why you're doing this and what the benefit is please.
> 
> Maybe something like
> 
> "When not holding the lock, there is a chance that the pte gets modified
>  under our feet, so we need to use the lockless API to make sure that
>  the entries remain consistent during the read."

I would gladly use this, if it makes sense for everyone.

@Lorenzo?

> Only arm64 makes use of it though, due to the contpte stuff and being
> unable to do it atomically.

Thanks!

> -- 
> Oscar Salvador
> SUSE Labs