[PATCHv2 6/8] arm_pmu: explicitly enable/disable SPIs at hotplug
geert at linux-m68k.org
Mon Feb 26 07:16:19 PST 2018
On Mon, Feb 5, 2018 at 5:42 PM, Mark Rutland <mark.rutland at arm.com> wrote:
> To support ACPI systems, we need to request IRQs before CPUs are
> hotplugged, and thus we need to request IRQs before we know their
> associated PMU.
> This is problematic if a PMU IRQ is pending out of reset, as it may be
> taken before we know the PMU, and thus the IRQ handler won't be able to
> handle it, leaving it screaming.
> To avoid such problems, lets request all IRQs in a disabled state, and
> explicitly enable/disable them at hotplug time, when we're sure the PMU
> has been probed.
> Signed-off-by: Mark Rutland <mark.rutland at arm.com>
This is now commit 6de3f79112cc26bf in v4.16-rc3, and causes a BUG during
CPU offlining (e.g. during system suspend, or during boot with
psci_checker: PSCI checker started using 6 CPUs
psci_checker: Starting hotplug tests
psci_checker: Trying to turn off and on again all CPUs
BUG: sleeping function called from invalid context at kernel/irq/manage.c:112
in_atomic(): 1, irqs_disabled(): 128, pid: 15, name: migration/1
no locks held by migration/1/15.
irq event stamp: 192
hardirqs last enabled at (191): [<00000000803c2507>]
hardirqs last disabled at (192): [<000000007f57ad28>] multi_cpu_stop+0x9c/0x140
softirqs last enabled at (0): [<0000000004ee1b58>]
softirqs last disabled at (0): [< (null)>] (null)
CPU: 1 PID: 15 Comm: migration/1 Not tainted 4.16.0-rc3-salvator-x #1651
Hardware name: Renesas Salvator-X board based on r8a7796 (DT)
psci: CPU1 killed.
Reverting that commit on v4.16-rc3 fixes the issue.
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert at linux-m68k.org
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
More information about the linux-arm-kernel