ACPI: processor_idle: use raw_safe_halt() in acpi_idle_play_dead()

Xen HVM guests were observed taking triple-faults when attempting to
online a previously offlined vCPU.

Investigation showed that the fault was coming from a failing call
to lockdep_assert_irqs_disabled(), in load_current_idt() which was
too early in the CPU bringup to actually catch the exception and
report the failure cleanly.

This was a false positive, caused by acpi_idle_play_dead() setting
the per-cpu hardirqs_enabled flag by calling safe_halt(). Switch it
to use raw_safe_halt() instead, which doesn't do so.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: 6.6+ <stable@vger.kernel.org> # 6.6+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
index 3a34a8c425fe4a673119d5ac7d9fef87ed145f38..55437f5e0c3aee4bf8e404b2e3b0977238401eb0 100644 (file)
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -592,7 +592,7 @@ static int acpi_idle_play_dead(struct cpuidle_device *dev, int index)
        while (1) {
 
                if (cx->entry_method == ACPI_CSTATE_HALT)
-                       safe_halt();
+                       raw_safe_halt();
                else if (cx->entry_method == ACPI_CSTATE_SYSTEMIO) {
                        io_idle(cx->address);
                } else