Re: [PATCH 3/5] irqchip/bcm2836: Make IPIs use handle_percpu_devid_irq()

From: Marc Zyngier
Date: Tue Dec 15 2020 - 10:47:40 EST


On 2020-12-15 15:39, Guenter Roeck wrote:
On 12/15/20 7:26 AM, Marc Zyngier wrote:
On 2020-12-15 15:21, Guenter Roeck wrote:
Hi Marc,

On 12/15/20 2:19 AM, Marc Zyngier wrote:
Hi Gunter,

On 2020-12-15 00:21, Guenter Roeck wrote:
On Mon, Nov 09, 2020 at 09:41:19AM +0000, Valentin Schneider wrote:
As done for the Arm GIC irqchips, move IPIs to handle_percpu_devid_irq() as
handle_percpu_devid_fasteoi_ipi() isn't actually required.

Signed-off-by: Valentin Schneider <valentin.schneider@xxxxxxx>

This patch results in boot failures (silent stall) for the qemu
raspi2 emulation. Unfortunately it can not be reverted because
handle_percpu_devid_fasteoi_ipi no longer exists in next-20201214,
so I don't know if it is the only problem.

This is odd. This works just fine for me on both the RPi2 and 3
emulation, running a full Debian userspace. Could this be caused
by the version of QEMU you are using? Here's what I have:

$ qemu-system-arm --version
QEMU emulator version 5.1.0 (Debian 1:5.1+dfsg-4+b1)


I used qemu 5.0 which - up to now - worked fine. Let me try with
5.1 and 5.2. Sorry, I should have tried first before bothering you.

No bother at all. If this works for you on more recent versions of
QEMU, that'd be an interesting data point. I'm also interested in
the result of the patch either way.


It doesn't work for me with qemu 5.1, nor with qemu 5.2. My userspace
is generated with buildroot, busybox-based, and very basic.

OK, so something is definitely different between our setups.
Mind pointing me to your config and your QEMU invocation?


Your patch fixes the problem for me, though, so feel free to add

Tested-by: Guenter Roeck <linux@xxxxxxxxxxxx>

if/when you submit it.

Thanks for that.

M.
--
Jazz is not dead. It just smells funny...