Re: [PATCH] pinctrl/amd: Use regular interrupt instead of chained

[Linus Walleij]

On Tue, May 23, 2017 at 11:23 PM, Thomas Gleixner <tglx@xxxxxxxxxxxxx> wrote:

> The AMD pinctrl driver uses a chained interrupt to demultiplex the GPIO
> interrupts. Kevin Vandeventer reported, that his new AMD Ryzen locks up
> hard on boot when the AMD pinctrl driver is initialized. The reason is an
> interrupt storm. It's not clear whether that's caused by hardware or
> firmware or both.
>
> Using chained interrupts on X86 is a dangerous endavour. If a system is
> misconfigured or the hardware buggy there is no safety net to catch an
> interrupt storm.
>
> Convert the driver to use a regular interrupt for the demultiplex
> handler. This allows the interrupt storm detector to catch the malfunction
> and lets the system boot up.
>
> This should be backported to stable because it's likely that more users run
> into this problem as the AMD Ryzen machines are spreading.
>
> Reported-by: Kevin Vandeventer
> Link: https://bugzilla.suse.com/show_bug.cgi?id=1034261
> Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>

Patch applied for fixes.

Hm, I wonder if there is a bunch of other x86 drivers that should just
request the IRQ?

Yours,
Linus Walleij