Re: [PATCH] cxl/pci: Fix irq oneshot expectations

[Dave Jiang <dave.jiang@intel.com>]

On 1/30/23 5:08 PM, Dan Williams wrote:
> The IRQ core expects that users of the default hardirq handler specify
> IRQF_ONESHOT to keep interrupts disabled until the threaded handler
> runs. That meets the CXL driver's expectations since it is an edge
> triggered MSI and this flag would have been passed by default using
> pci_request_irq() instead of devm_request_threaded_irq().
> 
> Fixes: a49aa8141b65 ("cxl/mem: Wire up event interrupts")
> Reported-by: kernel test robot <lkp@intel.com>
> Reported-by: Julia Lawall <julia.lawall@lip6.fr>
> Cc: Davidlohr Bueso <dave@stgolabs.net>
> Cc: Ira Weiny <ira.weiny@intel.com>
> Signed-off-by: Dan Williams <dan.j.williams@intel.com>

Reviewed-by: Dave Jiang <dave.jiang@intel.com>

> ---
>   drivers/cxl/pci.c |    3 ++-
>   1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c
> index ad2ebe7bfaeb..4cf9a2191602 100644
> --- a/drivers/cxl/pci.c
> +++ b/drivers/cxl/pci.c
> @@ -509,7 +509,8 @@ static int cxl_event_req_irq(struct cxl_dev_state *cxlds, u8 setting)
>   		return irq;
>   
>   	return devm_request_threaded_irq(dev, irq, NULL, cxl_event_thread,
> -					 IRQF_SHARED, NULL, dev_id);
> +					 IRQF_SHARED | IRQF_ONESHOT, NULL,
> +					 dev_id);
>   }
>   
>   static int cxl_event_get_int_policy(struct cxl_dev_state *cxlds,
>