Commit b4d16ab5 authored by Michael Ellerman's avatar Michael Ellerman

powerpc/time: Fix clockevent_decrementer initalisation for PR KVM

In the recent commit 8b78fdb0 ("powerpc/time: Use
clockevents_register_device(), fixing an issue with large
decrementer") we changed the way we initialise the decrementer
clockevent(s).

We no longer initialise the mult & shift values of
decrementer_clockevent itself.

This has the effect of breaking PR KVM, because it uses those values
in kvmppc_emulate_dec(). The symptom is guest kernels spin forever
mid-way through boot.

For now fix it by assigning back to decrementer_clockevent the mult
and shift values.

Fixes: 8b78fdb0 ("powerpc/time: Use clockevents_register_device(), fixing an issue with large decrementer")
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
parent 6ce7bff0
......@@ -989,6 +989,10 @@ static void register_decrementer_clockevent(int cpu)
printk_once(KERN_DEBUG "clockevent: %s mult[%x] shift[%d] cpu[%d]\n",
dec->name, dec->mult, dec->shift, cpu);
/* Set values for KVM, see kvm_emulate_dec() */
decrementer_clockevent.mult = dec->mult;
decrementer_clockevent.shift = dec->shift;
}
static void enable_large_decrementer(void)
......
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