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

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-ID: <20231228145416.GAZY2MGLY6THMkAZ2W@fat_crate.local>
Date: Thu, 28 Dec 2023 15:54:16 +0100
From: "Borislav Petkov (AMD)" <bp@...en8.de>
To: linux-pm@...r.kernel.org, forza@...nline.net
Cc: "Rafael J. Wysocki" <rafael@...nel.org>,
	Daniel Lezcano <daniel.lezcano@...aro.org>,
	lkml <linux-kernel@...r.kernel.org>
Subject: [PATCH] cpuidle: haltpoll: Do not enable interrupts when entering
 idle

Hi,

I think PeterZ's massaging from

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

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@...en8.de>

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@...nline.net>
Tested-by: <forza@...nline.net>
Signed-off-by: Borislav Petkov (AMD) <bp@...en8.de>
---
 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.

https://people.kernel.org/tglx/notes-about-netiquette