Re: [PATCH V2] spmi: pmic-arb: Enforce the ownership check optionally

From: Shawn Guo
Date: Tue Aug 22 2017 - 04:55:59 EST


On Mon, Aug 21, 2017 at 04:18:58PM -0700, Stephen Boyd wrote:
> On 08/18/2017 08:28 AM, Kiran Gunda wrote:
> > The peripheral ownership check is not necessary on single master
> > platforms. Hence, enforce the peripheral ownership check optionally.
> >
> > Signed-off-by: Kiran Gunda <kgunda@xxxxxxxxxxxxxx>
> > Tested-by: Shawn Guo <shawnguo@xxxxxxxxxx>
> > ---
>
> This sounds like a band-aid. Isn't the gpio driver going to keep probing
> all the pins that are not supposed to be accessed due to security
> constraints? What exactly is failing in the gpio case?

There is a platform_irq_count() call in pinctrl-spmi-gpio probe
function. Due to the owner check in spmi-pmic-arb IRQ domain
qpnpint_irq_domain_dt_translate() function, the call will return irq
number as zero and cause pmic_gpio_probe() fail with -EINVAL error.

[ 1.608516] [<ffff00000860e51c>] qpnpint_irq_domain_dt_translate+0x168/0x194
[ 1.613557] [<ffff000008117040>] irq_create_fwspec_mapping+0x17c/0x2d8
[ 1.620672] [<ffff000008117200>] irq_create_of_mapping+0x64/0x74
[ 1.627008] [<ffff0000087b4fac>] of_irq_get+0x54/0x64
[ 1.633169] [<ffff00000856b824>] platform_get_irq+0x20/0x150
[ 1.638117] [<ffff00000856b97c>] platform_irq_count+0x28/0x44
[ 1.643850] [<ffff0000083cf12c>] pmic_gpio_probe+0x50/0x544

Shawn