+ task_numa_compare-fix-check-for-kernel-thread.patch added to mm-unstable branch

+ task_numa_compare-fix-check-for-kernel-thread.patch added to mm-unstable branch

[Andrew Morton]

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The patch titled
     Subject: task_numa_compare: fix check for kernel thread
has been added to the -mm mm-unstable branch.  Its filename is
     task_numa_compare-fix-check-for-kernel-thread.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/task_numa_compare-fix-check-for-kernel-thread.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Andrew Morton <akpm@linux-foundation.org>
Subject: task_numa_compare: fix check for kernel thread
Date: Wed May 21 01:54:00 PM PDT 2025

Peter points out "!cur->mm is not the right way to determine a kernel
thread, PF_KTHREAD is.  Notably, there are kernel threads that have ->mm".

Link: https://lkml.kernel.org/r/20250521191114.GE24938@noisy.programming.kicks-ass.net
Fixes: 69cebdfa253b sched/numa: fix task swap by skipping kernel threads
Cc: Aubrey Li <aubrey.li@intel.com>
Cc: Ayush Jain <ayush.jain3@amd.com>
Cc: "Chen, Tim C" <tim.c.chen@intel.com>
Cc: Chen, Yu C <yu.c.chen@intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: K Prateek Nayak <kprateek.nayak@amd.com>
Cc: Libo Chen <libo.chen@oracle.com>
Cc: Madadi Vineeth Reddy <vineethr@linux.ibm.com>
Cc: Mel Gorman <mgorman <mgorman@suse.de>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Koutný <mkoutny@suse.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 kernel/sched/fair.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/kernel/sched/fair.c~task_numa_compare-fix-check-for-kernel-thread
+++ a/kernel/sched/fair.c
@@ -2274,7 +2274,7 @@ static bool task_numa_compare(struct tas
 	rcu_read_lock();
 	cur = rcu_dereference(dst_rq->curr);
 	if (cur && ((cur->flags & PF_EXITING) || is_idle_task(cur) ||
-		    !cur->mm))
+		    !(cur->flags & PF_KTHREAD)))
 		cur = NULL;
 
 	/*
_

Patches currently in -mm which might be from akpm@linux-foundation.org are

task_numa_compare-fix-check-for-kernel-thread.patch
mm-add-zblock-allocator-fix.patch
mm-add-zblock-allocator-fix-2.patch
mm-add-zblock-allocator-fix-2-fix.patch
mm-add-zblock-allocator-fix-3.patch
mm-zblock-avoid-failing-the-build-fix.patch