Re: [PATCH v4 1/3] mm: use targeted IPIs for TLB sync with lockless page table walkers

[Peter Zijlstra]

On Mon, Feb 02, 2026 at 09:23:07PM +0800, Lance Yang wrote:

> Hmm... we need MB rather than RMB on the sync side. Is that correct?
> 
> Walker:
> [W]active_lockless_pt_walk_mm = mm -> MB -> [L]page-tables
> 
> Sync:
> [W]page-tables -> MB -> [L]active_lockless_pt_walk_mm
> 

This can work -- but only if the walker and sync touch the same
page-table address.

Now, typically I would imagine they both share the p4d/pud address at
the very least, right?