Commit fa509ff8 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'locking-urgent-2021-03-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 

Pull locking fixes from Thomas Gleixner:
 "A couple of locking fixes:

   - A fix for the static_call mechanism so it handles unaligned
     addresses correctly.

   - Make u64_stats_init() a macro so every instance gets a seperate
     lockdep key.

   - Make seqcount_latch_init() a macro as well to preserve the static
     variable which is used for the lockdep key"

* tag 'locking-urgent-2021-03-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  seqlock,lockdep: Fix seqcount_latch_init()
  u64_stats,lockdep: Fix u64_stats_init() vs lockdep
  static_call: Fix the module key fixup
parents 75013c6c 4817a52b

include/linux/seqlock.h

+1 −4
Original line number Diff line number Diff line
@@ -664,10 +664,7 @@ typedef struct { 
 * seqcount_latch_init() - runtime initializer for seqcount_latch_t

 * @s: Pointer to the seqcount_latch_t instance

 */

static inline void seqcount_latch_init(seqcount_latch_t *s)

{

	seqcount_init(&s->seqcount);

}

#define seqcount_latch_init(s) seqcount_init(&(s)->seqcount)



/**

 * raw_read_seqcount_latch() - pick even/odd latch data copy

include/linux/u64_stats_sync.h

+4 −3
Original line number Diff line number Diff line
@@ -115,12 +115,13 @@ static inline void u64_stats_inc(u64_stats_t *p) 
}

#endif



#if BITS_PER_LONG == 32 && defined(CONFIG_SMP)

#define u64_stats_init(syncp)	seqcount_init(&(syncp)->seq)

#else

static inline void u64_stats_init(struct u64_stats_sync *syncp)

{

#if BITS_PER_LONG == 32 && defined(CONFIG_SMP)

	seqcount_init(&syncp->seq);

#endif

}

#endif



static inline void u64_stats_update_begin(struct u64_stats_sync *syncp)

{

kernel/static_call.c

+4 −3
Original line number Diff line number Diff line
@@ -349,7 +349,8 @@ static int static_call_add_module(struct module *mod) 
	struct static_call_site *site;



	for (site = start; site != stop; site++) {

		unsigned long addr = (unsigned long)static_call_key(site);

		unsigned long s_key = (long)site->key + (long)&site->key;

		unsigned long addr = s_key & ~STATIC_CALL_SITE_FLAGS;

		unsigned long key;



		/*
@@ -373,8 +374,8 @@ static int static_call_add_module(struct module *mod) 
			return -EINVAL;

		}



		site->key = (key - (long)&site->key) |

			    (site->key & STATIC_CALL_SITE_FLAGS);

		key |= s_key & STATIC_CALL_SITE_FLAGS;

		site->key = key - (long)&site->key;

	}



	return __static_call_init(mod, start, stop);