Re: [PATCH] irqchip/bcm-6345-l1: fix SMP support

From: Álvaro Fernández Rojas
Date: Tue Feb 23 2021 - 07:30:53 EST


Hi Florian,

Yes, you’re right, there seems to be a bug, because cpu_number_map() and cpu_logical_map() are returning the same when BCM6358 starts with CMT 1:
[ 4.662896] bcm6345_l1_irq_handle: smp_id=0 cpu_logical=1 cpu_number=1

Let’s see if I can fix it…

Best regards,
Álvaro.

> El 22 feb 2021, a las 22:00, Florian Fainelli <f.fainelli@xxxxxxxxx> escribió:
>
>
>
> On 2/22/2021 12:13 PM, Álvaro Fernández Rojas wrote:
>> Some BCM6358 devices start with Core #1 instead of Core #0.
>> Apart from that, SMP is restricted to 1 CPU since BCM6358 has a shared TLB,
>> which makes it impossible for the current SMP support to start both CPUs.
>>
>> The problem is that smp_processor_id() returns 0 and then cpu_logical_map()
>> converts that to 1, which accesses an uninitialized position of intc->cpus[],
>> resulting in a kernel panic.
>
> Sounds like you nee to correct the way the cpu_logical_map[] is
> populated then?
> --
> Florian