Commit 3f307891 authored by Steven Rostedt's avatar Steven Rostedt Committed by Linus Torvalds
Browse files

locking: add typecheck on irqsave and friends for correct flags 



There haave been several areas in the kernel where an int has been used for
flags in local_irq_save() and friends instead of a long.  This can cause some
hard to debug problems on some architectures.

This patch adds a typecheck inside the irqsave and restore functions to flag
these cases.

[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: build fix]
Signed-off-by: default avatarSteven Rostedt <srostedt@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent e0deaff4

include/linux/irqflags.h

+39 −15
Original line number Diff line number Diff line
@@ -11,6 +11,8 @@ 
#ifndef _LINUX_TRACE_IRQFLAGS_H

#define _LINUX_TRACE_IRQFLAGS_H



#include <linux/typecheck.h>



#ifdef CONFIG_TRACE_IRQFLAGS

  extern void trace_softirqs_on(unsigned long ip);

  extern void trace_softirqs_off(unsigned long ip);
@@ -59,10 +61,16 @@ 
#define local_irq_disable() \

	do { raw_local_irq_disable(); trace_hardirqs_off(); } while (0)

#define local_irq_save(flags)				\

	do { raw_local_irq_save(flags); trace_hardirqs_off(); } while (0)

	do {						\

		typecheck(unsigned long, flags);	\

		raw_local_irq_save(flags);		\

		trace_hardirqs_off();			\

	} while (0)





#define local_irq_restore(flags)			\

	do {						\

		typecheck(unsigned long, flags);	\

		if (raw_irqs_disabled_flags(flags)) {	\

			raw_local_irq_restore(flags);	\

			trace_hardirqs_off();		\
@@ -78,8 +86,16 @@ 
 */

# define raw_local_irq_disable()	local_irq_disable()

# define raw_local_irq_enable()		local_irq_enable()

# define raw_local_irq_save(flags)	local_irq_save(flags)

# define raw_local_irq_restore(flags)	local_irq_restore(flags)

# define raw_local_irq_save(flags)			\

	do {						\

		typecheck(unsigned long, flags);	\

		local_irq_save(flags);			\

	} while (0)

# define raw_local_irq_restore(flags)			\

	do {						\

		typecheck(unsigned long, flags);	\

		local_irq_restore(flags);		\

	} while (0)

#endif /* CONFIG_TRACE_IRQFLAGS_SUPPORT */



#ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT
@@ -89,7 +105,11 @@ 
		raw_safe_halt();				\

	} while (0)



#define local_save_flags(flags)		raw_local_save_flags(flags)

#define local_save_flags(flags)				\

	do {						\

		typecheck(unsigned long, flags);	\

		raw_local_save_flags(flags);		\

	} while (0)



#define irqs_disabled()						\

({								\
@@ -99,7 +119,11 @@ 
	raw_irqs_disabled_flags(_flags);			\

})



#define irqs_disabled_flags(flags)	raw_irqs_disabled_flags(flags)

#define irqs_disabled_flags(flags)		\

({						\

	typecheck(unsigned long, flags);	\

	raw_irqs_disabled_flags(flags);		\

})

#endif		/* CONFIG_X86 */



#endif

include/linux/spinlock.h

+56 −16
Original line number Diff line number Diff line
@@ -46,6 +46,7 @@ 
 *  linux/spinlock.h:     builds the final spin_*() APIs.

 */



#include <linux/typecheck.h>

#include <linux/preempt.h>

#include <linux/linkage.h>

#include <linux/compiler.h>
@@ -191,23 +192,53 @@ do { \ 


#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)



#define spin_lock_irqsave(lock, flags)	flags = _spin_lock_irqsave(lock)

#define read_lock_irqsave(lock, flags)	flags = _read_lock_irqsave(lock)

#define write_lock_irqsave(lock, flags)	flags = _write_lock_irqsave(lock)

#define spin_lock_irqsave(lock, flags)			\

	do {						\

		typecheck(unsigned long, flags);	\

		flags = _spin_lock_irqsave(lock);	\

	} while (0)

#define read_lock_irqsave(lock, flags)			\

	do {						\

		typecheck(unsigned long, flags);	\

		flags = _read_lock_irqsave(lock);	\

	} while (0)

#define write_lock_irqsave(lock, flags)			\

	do {						\

		typecheck(unsigned long, flags);	\

		flags = _write_lock_irqsave(lock);	\

	} while (0)



#ifdef CONFIG_DEBUG_LOCK_ALLOC

#define spin_lock_irqsave_nested(lock, flags, subclass)			\

	flags = _spin_lock_irqsave_nested(lock, subclass)

	do {								\

		typecheck(unsigned long, flags);			\

		flags = _spin_lock_irqsave_nested(lock, subclass);	\

	} while (0)

#else

#define spin_lock_irqsave_nested(lock, flags, subclass)			\

	flags = _spin_lock_irqsave(lock)

	do {								\

		typecheck(unsigned long, flags);			\

		flags = _spin_lock_irqsave(lock);			\

	} while (0)

#endif



#else



#define spin_lock_irqsave(lock, flags)	_spin_lock_irqsave(lock, flags)

#define read_lock_irqsave(lock, flags)	_read_lock_irqsave(lock, flags)

#define write_lock_irqsave(lock, flags)	_write_lock_irqsave(lock, flags)

#define spin_lock_irqsave(lock, flags)			\

	do {						\

		typecheck(unsigned long, flags);	\

		_spin_lock_irqsave(lock, flags);	\

	} while (0)

#define read_lock_irqsave(lock, flags)			\

	do {						\

		typecheck(unsigned long, flags);	\

		_read_lock_irqsave(lock, flags);	\

	} while (0)

#define write_lock_irqsave(lock, flags)			\

	do {						\

		typecheck(unsigned long, flags);	\

		_write_lock_irqsave(lock, flags);	\

	} while (0)

#define spin_lock_irqsave_nested(lock, flags, subclass)	\

	spin_lock_irqsave(lock, flags)
@@ -261,15 +292,24 @@ do { \ 
#endif



#define spin_unlock_irqrestore(lock, flags)		\

					_spin_unlock_irqrestore(lock, flags)

	do {						\

		typecheck(unsigned long, flags);	\

		_spin_unlock_irqrestore(lock, flags);	\

	} while (0)

#define spin_unlock_bh(lock)		_spin_unlock_bh(lock)



#define read_unlock_irqrestore(lock, flags)		\

					_read_unlock_irqrestore(lock, flags)

	do {						\

		typecheck(unsigned long, flags);	\

		_read_unlock_irqrestore(lock, flags);	\

	} while (0)

#define read_unlock_bh(lock)		_read_unlock_bh(lock)



#define write_unlock_irqrestore(lock, flags)		\

					_write_unlock_irqrestore(lock, flags)

	do {						\

		typecheck(unsigned long, flags);	\

		_write_unlock_irqrestore(lock, flags);	\

	} while (0)

#define write_unlock_bh(lock)		_write_unlock_bh(lock)



#define spin_trylock_bh(lock)	__cond_lock(lock, _spin_trylock_bh(lock))

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