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powerpc/pseries: Enable RAS hotplug events later

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Currently if the kernel receives a memory hot-unplug event early
enough, it may get stuck in an infinite loop in
dissolve_free_huge_pages(). This appears as a stall just after:

  pseries-hotplug-mem: Attempting to hot-remove XX LMB(s) at YYYYYYYY

It appears to be caused by "minimum_order" being uninitialized, due to
init_ras_IRQ() executing before hugetlb_init().

To correct this, extract the part of init_ras_IRQ() that enables
hotplug event processing and place it in the machine_late_initcall
phase, which is guaranteed to be after hugetlb_init() is called.

Signed-off-by: Sam Bobroff <sam.bobroff@au1.ibm.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
[mpe: Reorder the functions to make the diff readable]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This commit is contained in:
Sam Bobroff 2018-02-12 11:19:29 +11:00 committed by Michael Ellerman
parent 4dd5f8a99e
commit c9dccf1d07
1 changed files with 22 additions and 9 deletions
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31
arch/powerpc/platforms/pseries/ras.c
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@ -48,6 +48,28 @@ static irqreturn_t ras_epow_interrupt(int irq, void *dev_id);
static irqreturn_t ras_error_interrupt(int irq, void *dev_id);
/*
* Enable the hotplug interrupt late because processing them may touch other
* devices or systems (e.g. hugepages) that have not been initialized at the
* subsys stage.
*/
int __init init_ras_hotplug_IRQ(void)
{
struct device_node *np;
/* Hotplug Events */
np = of_find_node_by_path("/event-sources/hot-plug-events");
if (np != NULL) {
if (dlpar_workqueue_init() == 0)
request_event_sources_irqs(np, ras_hotplug_interrupt,
"RAS_HOTPLUG");
of_node_put(np);
}
return 0;
}
machine_late_initcall(pseries, init_ras_hotplug_IRQ);
/*
* Initialize handlers for the set of interrupts caused by hardware errors
* and power system events.
@ -66,15 +88,6 @@ static int __init init_ras_IRQ(void)
of_node_put(np);
}
/* Hotplug Events */
np = of_find_node_by_path("/event-sources/hot-plug-events");
if (np != NULL) {
if (dlpar_workqueue_init() == 0)
request_event_sources_irqs(np, ras_hotplug_interrupt,
"RAS_HOTPLUG");
of_node_put(np);
}
/* EPOW Events */
np = of_find_node_by_path("/event-sources/epow-events");
if (np != NULL) {