Commit 892ad5ac authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 

Pull locking updates from Ingo Molnar:
 "The main changes in this cycle were:

   - Add CONFIG_REFCOUNT_FULL=y to allow the disabling of the 'full'
     (robustness checked) refcount_t implementation with slightly lower
     runtime overhead. (Kees Cook)

     The lighter weight variant is the default. The two variants use the
     same API. Having this variant was a precondition by some
     maintainers to merge refcount_t cleanups.

   - Add lockdep support for rtmutexes (Peter Zijlstra)

   - liblockdep fixes and improvements (Sasha Levin, Ben Hutchings)

   - ... misc fixes and improvements"

* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (30 commits)
  locking/refcount: Remove the half-implemented refcount_sub() API
  locking/refcount: Create unchecked atomic_t implementation
  locking/rtmutex: Don't initialize lockdep when not required
  locking/selftest: Add RT-mutex support
  locking/selftest: Remove the bad unlock ordering test
  rt_mutex: Add lockdep annotations
  MAINTAINERS: Claim atomic*_t maintainership
  locking/x86: Remove the unused atomic_inc_short() methd
  tools/lib/lockdep: Remove private kernel headers
  tools/lib/lockdep: Hide liblockdep output from test results
  tools/lib/lockdep: Add dummy current_gfp_context()
  tools/include: Add IS_ERR_OR_NULL to err.h
  tools/lib/lockdep: Add empty __is_[module,kernel]_percpu_address
  tools/lib/lockdep: Include err.h
  tools/include: Add (mostly) empty include/linux/sched/mm.h
  tools/lib/lockdep: Use LDFLAGS
  tools/lib/lockdep: Remove double-quotes from soname
  tools/lib/lockdep: Fix object file paths used in an out-of-tree build
  tools/lib/lockdep: Fix compilation for 4.11
  tools/lib/lockdep: Don't mix fd-based and stream IO
  ...
parents 162b246e 5d6dec6f

MAINTAINERS

+10 −1
Original line number Diff line number Diff line
@@ -2322,6 +2322,15 @@ F: Documentation/devicetree/bindings/input/atmel,maxtouch.txt 
F:	drivers/input/touchscreen/atmel_mxt_ts.c

F:	include/linux/platform_data/atmel_mxt_ts.h



ATOMIC INFRASTRUCTURE

M:	Will Deacon <will.deacon@arm.com>

M:	Peter Zijlstra <peterz@infradead.org>

R:	Boqun Feng <boqun.feng@gmail.com>

L:	linux-kernel@vger.kernel.org

S:	Maintained

F:	arch/*/include/asm/atomic*.h

F:	include/*/atomic*.h



ATTO EXPRESSSAS SAS/SATA RAID SCSI DRIVER

M:	Bradley Grove <linuxdrivers@attotech.com>

L:	linux-scsi@vger.kernel.org
@@ -7555,7 +7564,7 @@ S: Maintained 
F:	drivers/ata/sata_promise.*



LIBLOCKDEP

M:	Sasha Levin <sasha.levin@oracle.com>

M:	Sasha Levin <alexander.levin@verizon.com>

S:	Maintained

F:	tools/lib/lockdep/

arch/Kconfig

+9 −0
Original line number Diff line number Diff line
@@ -867,4 +867,13 @@ config STRICT_MODULE_RWX 
config ARCH_WANT_RELAX_ORDER

	bool



config REFCOUNT_FULL

	bool "Perform full reference count validation at the expense of speed"

	help

	  Enabling this switches the refcounting infrastructure from a fast

	  unchecked atomic_t implementation to a fully state checked

	  implementation, which can be (slightly) slower but provides protections

	  against various use-after-free conditions that can be used in

	  security flaw exploits.



source "kernel/gcov/Kconfig"

arch/tile/lib/atomic_asm_32.S

+1 −2
Original line number Diff line number Diff line
@@ -24,8 +24,7 @@ 
 * has an opportunity to return -EFAULT to the user if needed.

 * The 64-bit routines just return a "long long" with the value,

 * since they are only used from kernel space and don't expect to fault.

 * Support for 16-bit ops is included in the framework but we don't provide

 * any (x86_64 has an atomic_inc_short(), so we might want to some day).

 * Support for 16-bit ops is included in the framework but we don't provide any.

 *

 * Note that the caller is advised to issue a suitable L1 or L2

 * prefetch on the address being manipulated to avoid extra stalls.

arch/x86/include/asm/atomic.h

+0 −13
Original line number Diff line number Diff line
@@ -246,19 +246,6 @@ static __always_inline int __atomic_add_unless(atomic_t *v, int a, int u) 
	return c;

}



/**

 * atomic_inc_short - increment of a short integer

 * @v: pointer to type int

 *

 * Atomically adds 1 to @v

 * Returns the new value of @u

 */

static __always_inline short int atomic_inc_short(short int *v)

{

	asm(LOCK_PREFIX "addw $1, %0" : "+m" (*v));

	return *v;

}



#ifdef CONFIG_X86_32

# include <asm/atomic64_32.h>

#else

include/linux/refcount.h

+37 −1
Original line number Diff line number Diff line
@@ -41,6 +41,7 @@ static inline unsigned int refcount_read(const refcount_t *r) 
	return atomic_read(&r->refs);

}



#ifdef CONFIG_REFCOUNT_FULL

extern __must_check bool refcount_add_not_zero(unsigned int i, refcount_t *r);

extern void refcount_add(unsigned int i, refcount_t *r);
@@ -48,10 +49,45 @@ extern __must_check bool refcount_inc_not_zero(refcount_t *r); 
extern void refcount_inc(refcount_t *r);



extern __must_check bool refcount_sub_and_test(unsigned int i, refcount_t *r);

extern void refcount_sub(unsigned int i, refcount_t *r);



extern __must_check bool refcount_dec_and_test(refcount_t *r);

extern void refcount_dec(refcount_t *r);

#else

static inline __must_check bool refcount_add_not_zero(unsigned int i, refcount_t *r)

{

	return atomic_add_unless(&r->refs, i, 0);

}



static inline void refcount_add(unsigned int i, refcount_t *r)

{

	atomic_add(i, &r->refs);

}



static inline __must_check bool refcount_inc_not_zero(refcount_t *r)

{

	return atomic_add_unless(&r->refs, 1, 0);

}



static inline void refcount_inc(refcount_t *r)

{

	atomic_inc(&r->refs);

}



static inline __must_check bool refcount_sub_and_test(unsigned int i, refcount_t *r)

{

	return atomic_sub_and_test(i, &r->refs);

}



static inline __must_check bool refcount_dec_and_test(refcount_t *r)

{

	return atomic_dec_and_test(&r->refs);

}



static inline void refcount_dec(refcount_t *r)

{

	atomic_dec(&r->refs);

}

#endif /* CONFIG_REFCOUNT_FULL */



extern __must_check bool refcount_dec_if_one(refcount_t *r);

extern __must_check bool refcount_dec_not_one(refcount_t *r);

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