[PATCH] cpuidle: haltpoll: Do not enable interrupts when entering idle

[Borislav Petkov (AMD)]

Hi,

I think PeterZ's massaging from

  https://lore.kernel.org/all/20230112194314.845371875@xxxxxxxxxxxxx/

missed one.

@Forza, if you want to have your real name in the patch tags below and
thus be part of git history, lemme know. If you don't want them there,
either.

Thx.

---
From: Borislav Petkov (AMD) <bp@xxxxxxxxx>

The cpuidle governors' ->enter() methods are supposed to be IRQ
invariant:

  5e26aa933911 ("cpuidle/poll: Ensure IRQs stay disabled after cpuidle_state::enter() calls")
  bb7b11258561 ("cpuidle: Move IRQ state validation")

Do that in the haltpoll governor too.

Fixes: 5e26aa933911 ("cpuidle/poll: Ensure IRQs stay disabled after cpuidle_state::enter() calls")
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218245
Reported-by: <forza@xxxxxxxxxxxx>
Tested-by: <forza@xxxxxxxxxxxx>
Signed-off-by: Borislav Petkov (AMD) <bp@xxxxxxxxx>
---
 drivers/cpuidle/cpuidle-haltpoll.c | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/drivers/cpuidle/cpuidle-haltpoll.c b/drivers/cpuidle/cpuidle-haltpoll.c
index e66df22f9695..d8515d5c0853 100644
--- a/drivers/cpuidle/cpuidle-haltpoll.c
+++ b/drivers/cpuidle/cpuidle-haltpoll.c
@@ -25,13 +25,12 @@ MODULE_PARM_DESC(force, "Load unconditionally");
 static struct cpuidle_device __percpu *haltpoll_cpuidle_devices;
 static enum cpuhp_state haltpoll_hp_state;
 
-static int default_enter_idle(struct cpuidle_device *dev,
-			      struct cpuidle_driver *drv, int index)
+static __cpuidle int default_enter_idle(struct cpuidle_device *dev,
+					struct cpuidle_driver *drv, int index)
 {
-	if (current_clr_polling_and_test()) {
-		local_irq_enable();
+	if (current_clr_polling_and_test())
 		return index;
-	}
+
 	arch_cpu_idle();
 	return index;
 }
-- 
2.42.0.rc0.25.ga82fb66fed25


-- 
Regards/Gruss,
    Boris.

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