6.6-stable review patch. If anyone has any objections, please let me know.
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From: Tejun Heo tj@kernel.org
commit aac8a59537dfc704ff344f1aacfd143c089ee20f upstream.
This reverts commit ca10d851b9ad0338c19e8e3089e24d565ebfffd7.
The commit allowed workqueue_apply_unbound_cpumask() to clear __WQ_ORDERED on now removed implicitly ordered workqueues. This was incorrect in that system-wide config change shouldn't break ordering properties of all workqueues. The reason why apply_workqueue_attrs() path was allowed to do so was because it was targeting the specific workqueue - either the workqueue had WQ_SYSFS set or the workqueue user specifically tried to change max_active, both of which indicate that the workqueue doesn't need to be ordered.
The implicitly ordered workqueue promotion was removed by the previous commit 3bc1e711c26b ("workqueue: Don't implicitly make UNBOUND workqueues w/ @max_active==1 ordered"). However, it didn't update this path and broke build. Let's revert the commit which was incorrect in the first place which also fixes build.
Signed-off-by: Tejun Heo tj@kernel.org Fixes: 3bc1e711c26b ("workqueue: Don't implicitly make UNBOUND workqueues w/ @max_active==1 ordered") Fixes: ca10d851b9ad ("workqueue: Override implicit ordered attribute in workqueue_apply_unbound_cpumask()") Cc: stable@vger.kernel.org # v6.6+ Signed-off-by: Tejun Heo tj@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- kernel/workqueue.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-)
--- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -5793,13 +5793,9 @@ static int workqueue_apply_unbound_cpuma list_for_each_entry(wq, &workqueues, list) { if (!(wq->flags & WQ_UNBOUND)) continue; - /* creating multiple pwqs breaks ordering guarantee */ - if (!list_empty(&wq->pwqs)) { - if (wq->flags & __WQ_ORDERED_EXPLICIT) - continue; - wq->flags &= ~__WQ_ORDERED; - } + if (wq->flags & __WQ_ORDERED) + continue;
ctx = apply_wqattrs_prepare(wq, wq->unbound_attrs, unbound_cpumask); if (IS_ERR(ctx)) {