Messages in this thread Patch in this message |  | | From | Greg Kroah-Hartman <> | Subject | [PATCH 4.7 20/31] x86/irq: Prevent force migration of irqs which are not in the vector domain | Date | Fri, 14 Oct 2016 14:55:04 +0200 |
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4.7-stable review patch. If anyone has any objections, please let me know.
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From: Mika Westerberg <mika.westerberg@linux.intel.com>
commit db91aa793ff984ac048e199ea1c54202543952fe upstream.
When a CPU is about to be offlined we call fixup_irqs() that resets IRQ affinities related to the CPU in question. The same thing is also done when the system is suspended to S-states like S3 (mem).
For each IRQ we try to complete any on-going move regardless whether the IRQ is actually part of x86_vector_domain. For each IRQ descriptor we fetch its chip_data, assume it is of type struct apic_chip_data and manipulate it by clearing old_domain mask etc. For irq_chips that are not part of the x86_vector_domain, like those created by various GPIO drivers, will find their chip_data being changed unexpectly.
Below is an example where GPIO chip owned by pinctrl-sunrisepoint.c gets corrupted after resume:
# cat /sys/kernel/debug/gpio gpiochip0: GPIOs 360-511, parent: platform/INT344B:00, INT344B:00: gpio-511 ( |sysfs ) in hi
# rtcwake -s10 -mmem <10 seconds passes>
# cat /sys/kernel/debug/gpio gpiochip0: GPIOs 360-511, parent: platform/INT344B:00, INT344B:00: gpio-511 ( |sysfs ) in ?
Note '?' in the output. It means the struct gpio_chip ->get function is NULL whereas before suspend it was there.
Fix this by first checking that the IRQ belongs to x86_vector_domain before we try to use the chip_data as struct apic_chip_data.
Reported-and-tested-by: Sakari Ailus <sakari.ailus@linux.intel.com> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Link: http://lkml.kernel.org/r/20161003101708.34795-1-mika.westerberg@linux.intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
--- arch/x86/kernel/apic/vector.c | 23 ++++++++++++++++++++--- 1 file changed, 20 insertions(+), 3 deletions(-)
--- a/arch/x86/kernel/apic/vector.c +++ b/arch/x86/kernel/apic/vector.c @@ -661,11 +661,28 @@ void irq_complete_move(struct irq_cfg *c */ void irq_force_complete_move(struct irq_desc *desc) { - struct irq_data *irqdata = irq_desc_get_irq_data(desc); - struct apic_chip_data *data = apic_chip_data(irqdata); - struct irq_cfg *cfg = data ? &data->cfg : NULL; + struct irq_data *irqdata; + struct apic_chip_data *data; + struct irq_cfg *cfg; unsigned int cpu; + /* + * The function is called for all descriptors regardless of which + * irqdomain they belong to. For example if an IRQ is provided by + * an irq_chip as part of a GPIO driver, the chip data for that + * descriptor is specific to the irq_chip in question. + * + * Check first that the chip_data is what we expect + * (apic_chip_data) before touching it any further. + */ + irqdata = irq_domain_get_irq_data(x86_vector_domain, + irq_desc_get_irq(desc)); + if (!irqdata) + return; + + data = apic_chip_data(irqdata); + cfg = data ? &data->cfg : NULL; + if (!cfg) return;
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