Re: [PATCH] xen/events: Fix interrupt lost during irq_disable and irq_enable

From: Boris Ostrovsky
Date: Mon Jul 31 2017 - 09:58:40 EST


On 07/29/2017 12:59 PM, Liu Shuo wrote:
> Here is a device has xen-pirq-MSI interrupt. Dom0 might lost interrupt
> during driver irq_disable/irq_enable. Here is the scenario,
> 1. irq_disable -> disable_dynirq -> mask_evtchn(irq channel)
> 2. dev interrupt raised by HW and Xen mark its evtchn as pending
> 3. irq_enable -> startup_pirq -> eoi_pirq ->
> clear_evtchn(channel of irq) -> clear pending status
> 4. consume_one_event process the irq event without pending bit assert
> which result in interrupt lost once
> 5. No HW interrupt raising anymore.
>
> Now use enable_dynirq for enable_pirq of xen_pirq_chip to remove
> eoi_pirq when irq_enable.
>
> Signed-off-by: Liu Shuo <shuo.a.liu@xxxxxxxxx>

Reviewed-by: Boris Ostrovsky <boris.ostrovsky@xxxxxxxxxx>