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 lk4XQiad ZAaDUePDpttQsFA4norke+bSep4yFGPhMh6wKiss10EopQ9gvsHxyQtcPPsk30AF/y+uqqU18LOWYx1tNn1ulxSAYzmowEDvoKe+H4rnaSfVBJHnZNbICXHXn7u8kbRXFgGPCjVhppfOWWGiys1bVeEFDks1VVu+kQZlNIUh9v23g3S7Rgtv9383ps0VMJDIInkAq45VfGUGKgnI/4RsSedinpKEAxTb0C1eAODaLjWQE+vbjYEsnCDWGIL6MzB8vx7asfnihK8Aqw5D+vOnm/uEvNbMkmaAGLuHXxWaK6d9gVOT6GSynSOrh5AIRCyAhRTVqQ0mFe+F1RPZTtEv0vae5aD9BUz6P+U6O4blVDi8hx4ylWsSxkMW/RMZHmm8KEBRto6d+cCub/Nst2FLi/zzrJQ== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 On Mon, Oct 19, 2026 at 11:04:12PM -0400, Gregory Price wrote: > On Tue, Oct 20, 2026 at 12:49:37PM +1100, Balbir Singh wrote: > > > diff --git a/mm/vmscan.c b/mm/vmscan.c > > > index e82ba737c028d..90f7a7bf4e426 100644 > > > --- a/mm/vmscan.c > > > +++ b/mm/vmscan.c > > > @@ -8180,7 +8180,7 @@ int user_proactive_reclaim(char *buf, > > > } else { > > > struct scan_control sc = { > > > .gfp_mask = current_gfp_context(gfp_mask), > > > - .reclaim_idx = gfp_zone(gfp_mask), > > > + .reclaim_idx = MAX_NR_ZONES - 1, > > > .proactive_swappiness = swappiness == -1 ? NULL : &swappiness, > > > .priority = DEF_PRIORITY, > > > .may_writepage = 1, > > > > > > I just noticed some other issues with this code, in terms of honouring > > zone_reclaim_node (not related to this patch). I'll send out fixes, for > > this patch. > > I'm shocked, I tell you, shocked! > > These are all things I accidentally ran into by just uh... using the > interface. I'm absolutely positive these interfaces are full of bugs. > :) I was looking at making may_writepage and may_unmap align with the constraints of node zone reclaim, .may_writepage = !!(node_reclaim_mode & RECLAIM_WRITE), and .may_unmap = !!(node_reclaim_mode & RECLAIM_UNMAP), which may violate the contract for proactive reclaim. Proactive reclaim itself tries to be compatible with cgroups reclaim interface, so it sets these values to 1. I still feel it is a violation of default node reclaim parameters, but not sure if it needs to be fixed up. Balbir