Re: [kvm-unit-tests PATCH 06/10] arm/arm64: gic: Check spurious and bad_sender in the active test

[Auger Eric <eric.auger@redhat.com>]

Hi Alexandru,

On 11/25/20 4:51 PM, Alexandru Elisei wrote:
> The gicv{2,3}-active test sends an IPI from the boot CPU to itself, then
> checks that the interrupt has been received as expected. The
> ipi_clear_active_handler() clears the active state of the interrupt with a
> write to the GICD_ICACTIVER register instead of writing the to EOI
> register.
> 
> When acknowledging the interrupt it is possible to get back an spurious
> interrupt ID (ID 1023), and the interrupt handler increments the number of
> spurious interrupts received on the current processor. However, this is not
> checked at the end of the test. Let's also check for spurious interrupts,
> like the IPI test does.
> 
> For IPIs on GICv2, the value returned by a read of the GICC_IAR register
> performed when acknowledging the interrupt also contains the sender CPU
> ID. Add a check for that too.
> 
> Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>

Eric
> ---
>  arm/gic.c | 8 +++++---
>  1 file changed, 5 insertions(+), 3 deletions(-)
> 
> diff --git a/arm/gic.c b/arm/gic.c
> index bcb834406d23..5727d72a0ef3 100644
> --- a/arm/gic.c
> +++ b/arm/gic.c
> @@ -125,12 +125,12 @@ static void check_spurious(void)
>  	}
>  }
>  
> -static void check_ipi_sender(u32 irqstat)
> +static void check_ipi_sender(u32 irqstat, int sender)
>  {
>  	if (gic_version() == 2) {
>  		int src = (irqstat >> 10) & 7;
>  
> -		if (src != IPI_SENDER)
> +		if (src != sender)
>  			bad_sender[smp_processor_id()] = src;
>  	}
>  }
> @@ -155,7 +155,7 @@ static void ipi_handler(struct pt_regs *regs __unused)
>  		 */
>  		if (gic_version() == 2)
>  			smp_rmb();
> -		check_ipi_sender(irqstat);
> +		check_ipi_sender(irqstat, IPI_SENDER);
>  		check_irqnr(irqnr);
>  		smp_wmb(); /* pairs with smp_rmb in check_acked */
>  		++acked[smp_processor_id()];
> @@ -382,6 +382,7 @@ static void ipi_clear_active_handler(struct pt_regs *regs __unused)
>  
>  		writel(val, base + GICD_ICACTIVER);
>  
> +		check_ipi_sender(irqstat, smp_processor_id());
>  		check_irqnr(irqnr);
>  		++acked[smp_processor_id()];
>  	} else {
> @@ -394,6 +395,7 @@ static void run_active_clear_test(void)
>  	report_prefix_push("active");
>  	setup_irq(ipi_clear_active_handler);
>  	ipi_test_self();
> +	check_spurious();
>  	report_prefix_pop();
>  }
>  
>