6.17-stable review patch. If anyone has any objections, please let me know.
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From: Zqiang qiang.zhang@linux.dev
[ Upstream commit a257e974210320ede524f340ffe16bf4bf0dda1e ]
For PREEMPT_RT=y kernels, the deferred_irq_workfn() is executed in the per-cpu irq_work/* task context and not disable-irq, if the rq returned by container_of() is current CPU's rq, the following scenarios may occur:
lock(&rq->__lock); <Interrupt> lock(&rq->__lock);
This commit use IRQ_WORK_INIT_HARD() to replace init_irq_work() to initialize rq->scx.deferred_irq_work, make the deferred_irq_workfn() is always invoked in hard-irq context.
Signed-off-by: Zqiang qiang.zhang@linux.dev Signed-off-by: Tejun Heo tj@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- kernel/sched/ext.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/kernel/sched/ext.c b/kernel/sched/ext.c index 1e4740de66c28..16a7ae9b29ae4 100644 --- a/kernel/sched/ext.c +++ b/kernel/sched/ext.c @@ -5377,7 +5377,7 @@ void __init init_sched_ext_class(void) BUG_ON(!zalloc_cpumask_var_node(&rq->scx.cpus_to_kick_if_idle, GFP_KERNEL, n)); BUG_ON(!zalloc_cpumask_var_node(&rq->scx.cpus_to_preempt, GFP_KERNEL, n)); BUG_ON(!zalloc_cpumask_var_node(&rq->scx.cpus_to_wait, GFP_KERNEL, n)); - init_irq_work(&rq->scx.deferred_irq_work, deferred_irq_workfn); + rq->scx.deferred_irq_work = IRQ_WORK_INIT_HARD(deferred_irq_workfn); init_irq_work(&rq->scx.kick_cpus_irq_work, kick_cpus_irq_workfn);
if (cpu_online(cpu))