Re: [PATCH] locking/lockdep: Dump state of percpu_rwsem upon hung up.

[Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>]

From 2642b4a1904259384f2018ea8df03ac49509c57a Mon Sep 17 00:00:00 2001
From: Tetsuo Handa <penguin-kernel@I-love.SKAURA.ne.jp>
Date: Tue, 10 Jul 2018 15:01:20 +0900
Subject: [PATCH] locking/rwsem: Convert the other sem->count to 'atomic_long_t'

Since "locking/rwsem: Convert sem->count to 'atomic_long_t'" forgot to
convert "struct rw_semaphore"->count in linux/rwsem-spinlock.h which is
used when CONFIG_RWSEM_GENERIC_SPINLOCK=y, trying to access it in MIPS
architecture causes build error due to type mismatch.

  error: passing argument 1 of 'atomic_long_read' from incompatible pointer type [-Werror=incompatible-pointer-types]
  note: expected 'const atomic_long_t * {aka const struct <anonymous> *}' but argument is of type '__s32 * {aka int *}'

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SKAURA.ne.jp>
Reported-by: kbuild test robot <lkp@intel.com>
Fixes: 8ee62b1870be8e63 ("locking/rwsem: Convert sem->count to 'atomic_long_t'")
Cc: stable <stable@vger.kernel.org> # v4.8+
Cc: Jason Low <jason.low2@hpe.com>
Cc: Peter Zijlstra <peterz@infradead.org>
---
 include/linux/rwsem-spinlock.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/linux/rwsem-spinlock.h b/include/linux/rwsem-spinlock.h
index e475683..1164965 100644
--- a/include/linux/rwsem-spinlock.h
+++ b/include/linux/rwsem-spinlock.h
@@ -22,7 +22,7 @@
  * - if wait_list is not empty, then there are processes waiting for the semaphore
  */
 struct rw_semaphore {
-	__s32			count;
+	atomic_long_t		count;
 	raw_spinlock_t		wait_lock;
 	struct list_head	wait_list;
 #ifdef CONFIG_DEBUG_LOCK_ALLOC
-- 
2.7.4