Messages in this thread | | | Subject | Re: BUG?: kernel does not (re)set irq smp_affinity to reboot_cpu | From | Marc Zyngier <> | Date | Mon, 27 Jun 2016 10:13:05 +0100 |
| |
[Thanks Maxime for pointing me to this discussion, +RMK]
Hi Hans,
On 26/06/16 17:00, Hans de Goede wrote: > Hi, > > I've just spend most of my Sunday debugging a problem > where Allwinner ARM SoC based boards will not shutdown when > using a Fedora 24 userland, where as the exact same > kernel works fine with Fedora 22. > > It turns out that irq-balanced is to blame. In Fedora 24 > it pins the i2c controller, which talks to the pmic > which is needed for poweroff to cpu-id 1: > > [root@localhost ~]# cat /proc/irq/49/smp_affinity > 2 > > Where as the reboot_cpu is cpu-id 0 and with > cpu 1 disabled at poweroff time, the i2c transfer > never gets past its first step leading to an i2c > driver timeout + kernel panic due to machine_power_off() > returning. > > As a workaround I can stop irq-balanced and do: > > echo 3 > /proc/irq/49/smp_affinity > > Before doing poweroff and then everything works as > expected again. > > Now the question is how to fix this?
[...]
I'm wondering if that's not an effect of this patch:
https://lkml.org/lkml/2015/9/24/138
missing on the ARM side (the corresponding arm64 patch is 217d453d473c).
Otherwise, can you instrument the GIC set_affinity method and find out if we're even trying to move this IRQ away from the CPU that is being torn down?
Thanks,
M. -- Jazz is not dead. It just smells funny...
| |