redonkable
/
alistair23-linux
1
0
Fork 0
Code Releases Activity

x86/irq: Prevent force migration of irqs which are not in the vector domain 

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>
Cc: stable@vger.kernel.org # 4.4+
Link: http://lkml.kernel.org/r/20161003101708.34795-1-mika.westerberg@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
hifive-unleashed-5.1
Mika Westerberg 2016-10-03 13:17:08 +03:00 committed by Thomas Gleixner
parent 597f03f9d1
commit db91aa793f
1 changed files with 20 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

23
arch/x86/kernel/apic/vector.c
View File

@ -661,11 +661,28 @@ void irq_complete_move(struct irq_cfg *cfg)
*/
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;