linux-kernel - [PATCH v4] PM: Fix symbol export for _SIMPLE_ variants of _PM

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: <20230922054552.3570-1-raag.jadav@intel.com>
Date:   Fri, 22 Sep 2023 11:15:52 +0530
From:   Raag Jadav <raag.jadav@...el.com>
To:     rafael@...nel.org, len.brown@...el.com, pavel@....cz,
        Jonathan.Cameron@...wei.com, paul@...pouillou.net,
        andriy.shevchenko@...ux.intel.com, rf@...nsource.cirrus.com
Cc:     linux-pm@...r.kernel.org, linux-kernel@...r.kernel.org,
        mallikarjunappa.sangannavar@...el.com, bala.senthil@...el.com,
        Raag Jadav <raag.jadav@...el.com>
Subject: [PATCH v4] PM: Fix symbol export for _SIMPLE_ variants of _PM_OPS()

Currently EXPORT_*_SIMPLE_DEV_PM_OPS() use EXPORT_*_DEV_PM_OPS() set
of macros to export dev_pm_ops symbol, which export the symbol in case
CONFIG_PM=y but don't take CONFIG_PM_SLEEP into consideration.

Since _SIMPLE_ variants of _PM_OPS() do not include runtime PM handles
and are only used in case CONFIG_PM_SLEEP=y, we should not be exporting
dev_pm_ops symbol for them in case CONFIG_PM_SLEEP=n.

This can be fixed by having two distinct set of export macros for both
_RUNTIME_ and _SIMPLE_ variants of _PM_OPS(), such that the export of
dev_pm_ops symbol used in each variant depends on CONFIG_PM and
CONFIG_PM_SLEEP respectively.

Introduce _DEV_SLEEP_PM_OPS() set of export macros for _SIMPLE_ variants
of _PM_OPS(), which export dev_pm_ops symbol only in case CONFIG_PM_SLEEP=y
and discard it otherwise.

Fixes: 34e1ed189fab ("PM: Improve EXPORT_*_DEV_PM_OPS macros")
Signed-off-by: Raag Jadav <raag.jadav@...el.com>
---
PS: This is a standalone fix and works without updating existing drivers.

Changes since v3:
- Rename _PM_OPS macro to _DISCARD_PM_OPS

Changes since v2:
- Drop redundant patches

Changes since v1:
- Update drivers to new set of macros

 include/linux/pm.h | 43 +++++++++++++++++++++++++++++--------------
 1 file changed, 29 insertions(+), 14 deletions(-)

diff --git a/include/linux/pm.h b/include/linux/pm.h
index 1400c37b29c7..629c1633bbd0 100644
--- a/include/linux/pm.h
+++ b/include/linux/pm.h
@@ -374,24 +374,39 @@ const struct dev_pm_ops name = { \
 	RUNTIME_PM_OPS(runtime_suspend_fn, runtime_resume_fn, idle_fn) \
 }
 
-#ifdef CONFIG_PM
-#define _EXPORT_DEV_PM_OPS(name, license, ns)				\
+#define _EXPORT_PM_OPS(name, license, ns)				\
 	const struct dev_pm_ops name;					\
 	__EXPORT_SYMBOL(name, license, ns);				\
 	const struct dev_pm_ops name
-#define EXPORT_PM_FN_GPL(name)		EXPORT_SYMBOL_GPL(name)
-#define EXPORT_PM_FN_NS_GPL(name, ns)	EXPORT_SYMBOL_NS_GPL(name, ns)
-#else
-#define _EXPORT_DEV_PM_OPS(name, license, ns)				\
+
+#define _DISCARD_PM_OPS(name, license, ns)				\
 	static __maybe_unused const struct dev_pm_ops __static_##name
+
+#ifdef CONFIG_PM
+#define _EXPORT_DEV_PM_OPS(name, license, ns)		_EXPORT_PM_OPS(name, license, ns)
+#define EXPORT_PM_FN_GPL(name)				EXPORT_SYMBOL_GPL(name)
+#define EXPORT_PM_FN_NS_GPL(name, ns)			EXPORT_SYMBOL_NS_GPL(name, ns)
+#else
+#define _EXPORT_DEV_PM_OPS(name, license, ns)		_DISCARD_PM_OPS(name, license, ns)
 #define EXPORT_PM_FN_GPL(name)
 #define EXPORT_PM_FN_NS_GPL(name, ns)
 #endif
 
-#define EXPORT_DEV_PM_OPS(name) _EXPORT_DEV_PM_OPS(name, "", "")
-#define EXPORT_GPL_DEV_PM_OPS(name) _EXPORT_DEV_PM_OPS(name, "GPL", "")
-#define EXPORT_NS_DEV_PM_OPS(name, ns) _EXPORT_DEV_PM_OPS(name, "", #ns)
-#define EXPORT_NS_GPL_DEV_PM_OPS(name, ns) _EXPORT_DEV_PM_OPS(name, "GPL", #ns)
+#ifdef CONFIG_PM_SLEEP
+#define _EXPORT_DEV_SLEEP_PM_OPS(name, license, ns)	_EXPORT_PM_OPS(name, license, ns)
+#else
+#define _EXPORT_DEV_SLEEP_PM_OPS(name, license, ns)	_DISCARD_PM_OPS(name, license, ns)
+#endif
+
+#define EXPORT_DEV_PM_OPS(name)				_EXPORT_DEV_PM_OPS(name, "", "")
+#define EXPORT_GPL_DEV_PM_OPS(name)			_EXPORT_DEV_PM_OPS(name, "GPL", "")
+#define EXPORT_NS_DEV_PM_OPS(name, ns)			_EXPORT_DEV_PM_OPS(name, "", #ns)
+#define EXPORT_NS_GPL_DEV_PM_OPS(name, ns)		_EXPORT_DEV_PM_OPS(name, "GPL", #ns)
+
+#define EXPORT_DEV_SLEEP_PM_OPS(name)			_EXPORT_DEV_SLEEP_PM_OPS(name, "", "")
+#define EXPORT_GPL_DEV_SLEEP_PM_OPS(name)		_EXPORT_DEV_SLEEP_PM_OPS(name, "GPL", "")
+#define EXPORT_NS_DEV_SLEEP_PM_OPS(name, ns)		_EXPORT_DEV_SLEEP_PM_OPS(name, "", #ns)
+#define EXPORT_NS_GPL_DEV_SLEEP_PM_OPS(name, ns)	_EXPORT_DEV_SLEEP_PM_OPS(name, "GPL", #ns)
 
 /*
  * Use this if you want to use the same suspend and resume callbacks for suspend
@@ -404,19 +419,19 @@ const struct dev_pm_ops name = { \
 	_DEFINE_DEV_PM_OPS(name, suspend_fn, resume_fn, NULL, NULL, NULL)
 
 #define EXPORT_SIMPLE_DEV_PM_OPS(name, suspend_fn, resume_fn) \
-	EXPORT_DEV_PM_OPS(name) = { \
+	EXPORT_DEV_SLEEP_PM_OPS(name) = { \
 		SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
 	}
 #define EXPORT_GPL_SIMPLE_DEV_PM_OPS(name, suspend_fn, resume_fn) \
-	EXPORT_GPL_DEV_PM_OPS(name) = { \
+	EXPORT_GPL_DEV_SLEEP_PM_OPS(name) = { \
 		SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
 	}
 #define EXPORT_NS_SIMPLE_DEV_PM_OPS(name, suspend_fn, resume_fn, ns)	\
-	EXPORT_NS_DEV_PM_OPS(name, ns) = { \
+	EXPORT_NS_DEV_SLEEP_PM_OPS(name, ns) = { \
 		SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
 	}
 #define EXPORT_NS_GPL_SIMPLE_DEV_PM_OPS(name, suspend_fn, resume_fn, ns)	\
-	EXPORT_NS_GPL_DEV_PM_OPS(name, ns) = { \
+	EXPORT_NS_GPL_DEV_SLEEP_PM_OPS(name, ns) = { \
 		SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
 	}
 
-- 
2.17.1