Re: [patch V2 2/6] genirq: Fix misleading synchronize_irq() documentation

[Peter Zijlstra]

On Fri, Jun 28, 2019 at 01:11:50PM +0200, Thomas Gleixner wrote:
> The function might sleep, so it cannot be called from interrupt
> context. Not even with care.
> 
> Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> ---
>  kernel/irq/manage.c |    3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> --- a/kernel/irq/manage.c
> +++ b/kernel/irq/manage.c
> @@ -96,7 +96,8 @@ EXPORT_SYMBOL(synchronize_hardirq);
>   *	to complete before returning. If you use this function while
>   *	holding a resource the IRQ handler may need you will deadlock.
>   *
> - *	This function may be called - with care - from IRQ context.
> + *	Can only be called from preemptible code as it might sleep when
> + *	an interrupt thread is associated to @irq.
>   */
>  void synchronize_irq(unsigned int irq)
>  {

+	might_sleep();

?