From: David Woodhouse <dwmw@amazon.co.uk>
Date: Fri, 27 Oct 2023 18:36:51 +0000 (+0100)
Subject: ACPI: processor_idle: use raw_safe_halt() in acpi_idle_play_dead()
X-Git-Tag: v6.6.7~431
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=73111754b5260ce3b8cebcb31b3fdcabfd5e9401;p=platform%2Fkernel%2Flinux-starfive.git

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

commit 9bb69ba4c177dccaa1f5b5cbdf80b67813328348 upstream.

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
index 3a34a8c..55437f5 100644
--- 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