RE: [PATCH] megaraid_sas: init tasklet earlier

[Sumit Saxena <sumit.saxena@avagotech.com>]

> -----Original Message-----
> From: Tomas Henzl [mailto:thenzl@redhat.com]
> Sent: Tuesday, August 25, 2015 7:02 PM
> To: linux-scsi@vger.kernel.org
> Cc: kashyap.desai@avagotech.com; kiran-kumar.kasturi@avagotech.com;
> Sumit.Saxena@avagotech.com
> Subject: [PATCH] megaraid_sas: init tasklet earlier
>
> It may happen (kdump), that an interrupt is invoked just after the
setup_irqs
> function was called but before the tasklet was initialised.
> At this phase the hw ints should have been disabled, but for unknown
reason this
> mechanism seems to not work properly.
>
> Signed-off-by: Tomas Henzl <thenzl@redhat.com>
> ---
>  drivers/scsi/megaraid/megaraid_sas_base.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/scsi/megaraid/megaraid_sas_base.c
> b/drivers/scsi/megaraid/megaraid_sas_base.c
> index 71b884dae2..c8e0c6de80 100644
> --- a/drivers/scsi/megaraid/megaraid_sas_base.c
> +++ b/drivers/scsi/megaraid/megaraid_sas_base.c
> @@ -4627,6 +4627,9 @@ static int megasas_init_fw(struct megasas_instance
> *instance)
>  		"current msix/online cpus\t: (%d/%d)\n",
>  		instance->msix_vectors, (unsigned int)num_online_cpus());
>
> +	tasklet_init(&instance->isr_tasklet, instance->instancet->tasklet,
> +		(unsigned long)instance);
> +
>  	if (instance->msix_vectors ?
>  		megasas_setup_irqs_msix(instance, 1) :
>  		megasas_setup_irqs_ioapic(instance))
> @@ -4647,9 +4650,6 @@ static int megasas_init_fw(struct megasas_instance
> *instance)
>  	if (instance->instancet->init_adapter(instance))
>  		goto fail_init_adapter;
>
> -	tasklet_init(&instance->isr_tasklet, instance->instancet->tasklet,
> -		(unsigned long)instance);
> -
>  	instance->instancet->enable_intr(instance);
>
>  	printk(KERN_ERR "megasas: INIT adapter done\n");


Patch looks harmless and it fixes your problem then it's fine. But we need
to know the reason why interrupts are coming even if they are not enabled
by that time. Can you provide controller's FW version ? I would like to
try this locally.

> --
> 2.4.3