From 29b306c44eb5eefdfa02d6ba1205f479f82fb088 Mon Sep 17 00:00:00 2001
From: Frederic Weisbecker <frederic@kernel.org>
Date: Tue, 30 Sep 2025 15:21:33 +0200
Subject: PCI: Flush PCI probe workqueue on cpuset isolated partition change

The HK_TYPE_DOMAIN housekeeping cpumask is now modifiable at runtime. In
order to synchronize against PCI probe works and make sure that no
asynchronous probing is still pending or executing on a newly isolated
CPU, the housekeeping subsystem must flush the PCI probe works.

However the PCI probe works can't be flushed easily since they are
queued to the main per-CPU workqueue pool.

Solve this with creating a PCI probe-specific pool and provide and use
the appropriate flushing API.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Marco Crivellari <marco.crivellari@suse.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Waiman Long <longman@redhat.com>
Cc: linux-pci@vger.kernel.org
---
 kernel/sched/isolation.c | 2 ++
 1 file changed, 2 insertions(+)

(limited to 'kernel')

diff --git a/kernel/sched/isolation.c b/kernel/sched/isolation.c
index 160b3fcab209..1e4c3154b0a4 100644
--- a/kernel/sched/isolation.c
+++ b/kernel/sched/isolation.c
@@ -8,6 +8,7 @@
  *
  */
 #include <linux/sched/isolation.h>
+#include <linux/pci.h>
 #include "sched.h"
 
 enum hk_flags {
@@ -144,6 +145,7 @@ int housekeeping_update(struct cpumask *isol_mask)
 
 	synchronize_rcu();
 
+	pci_probe_flush_workqueue();
 	mem_cgroup_flush_workqueue();
 	vmstat_flush_workqueue();
 
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