(arm-land adventures 1/3 take2 will have to wait, my cup runeth over)
v4.14..v4.15 timer handling changes including calling kvm_timer_vcpu_load()
during kvm_preempt_ops.sched_in and taking vgic_dist.lpi_list_lock in the
timer interrupt handler required locks for which locking rules/context had
been changed be converted to raw_spinlock_t...
Quoting virt/kvm/arm/vgic/vgic.c:
* Locking order is always:
* kvm->lock (mutex)
* its->cmd_lock (mutex)
* its->its_lock (mutex)
* vgic_cpu->ap_list_lock must be taken with IRQs disabled
* kvm->lpi_list_lock must be taken with IRQs disabled
* vgic_irq->irq_lock must be taken with IRQs disabled
*
* As the ap_list_lock might be taken from the timer interrupt handler,
* we have to disable IRQs before taking this lock and everything lower
* than it.
...and fixed the obvious bricking consequence of those changes for RT,
but left an RT specific kvm unit test timer failure in its wake. Handling
phys_timer in hard interrupt context as expected cures that failure.
Pre:
PASS selftest-setup (2 tests)
PASS selftest-vectors-kernel (2 tests)
PASS selftest-vectors-user (2 tests)
PASS selftest-smp (65 tests)
PASS pci-test (1 tests)
PASS pmu (3 tests)
PASS gicv2-ipi (3 tests)
PASS gicv3-ipi (3 tests)
PASS gicv2-active (1 tests)
PASS gicv3-active (1 tests)
PASS psci (4 tests)
FAIL timer (8 tests, 1 unexpected failures)
Post:
PASS selftest-setup (2 tests)
PASS selftest-vectors-kernel (2 tests)
PASS selftest-vectors-user (2 tests)
PASS selftest-smp (65 tests)
PASS pci-test (1 tests)
PASS pmu (3 tests)
PASS gicv2-ipi (3 tests)
PASS gicv3-ipi (3 tests)
PASS gicv2-active (1 tests)
PASS gicv3-active (1 tests)
PASS psci (4 tests)
PASS timer (8 tests)
Signed-off-by: Mike Galbraith <efa...@gmx.de>
---
virt/kvm/arm/arch_timer.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/virt/kvm/arm/arch_timer.c
+++ b/virt/kvm/arm/arch_timer.c
@@ -634,7 +634,7 @@ void kvm_timer_vcpu_init(struct kvm_vcpu
hrtimer_init(&timer->bg_timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
timer->bg_timer.function = kvm_bg_timer_expire;
- hrtimer_init(&timer->phys_timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
+ hrtimer_init(&timer->phys_timer, CLOCK_MONOTONIC,
HRTIMER_MODE_ABS_HARD);
timer->phys_timer.function = kvm_phys_timer_expire;
vtimer->irq.irq = default_vtimer_irq.irq;
