[PATCH] x86: uninitialized spinlocks in tlb_uv.c

[PATCH] x86: uninitialized spinlocks in tlb_uv.c

[Cliff Wickman]

From: Cliff Wickman <cpw@sgi.com>

Initialize two spinlocks in tlb_uv.c.

The lack of explicit initialization seems to be functionally harmless (the
locks are initialized to 0's), but it is diagnosed when these are turned on:
        CONFIG_DEBUG_SPINLOCK=y
        CONFIG_DEBUG_MUTEXES=y
        CONFIG_DEBUG_LOCK_ALLOC=y
        CONFIG_LOCKDEP=y

Signed-off-by: Cliff Wickman <cpw@sgi.com>
---
 arch/x86/platform/uv/tlb_uv.c |    2 ++
 1 file changed, 2 insertions(+)

Index: 120113.linux-3.2.1/arch/x86/platform/uv/tlb_uv.c
===================================================================
--- 120113.linux-3.2.1.orig/arch/x86/platform/uv/tlb_uv.c
+++ 120113.linux-3.2.1/arch/x86/platform/uv/tlb_uv.c
@@ -1851,6 +1851,8 @@ static void __init init_per_cpu_tunables
 		bcp->cong_reps			= congested_reps;
 		bcp->cong_period		= congested_period;
 		bcp->clocks_per_100_usec =	usec_2_cycles(100);
+		spin_lock_init(&bcp->queue_lock);
+		spin_lock_init(&bcp->uvhub_lock);
 	}
 }
 

[tip:x86/urgent] x86/uv: Fix uninitialized spinlocks

[tip-bot for Cliff Wickman]

Commit-ID:  d2ebc71d472020bc30e29afe8c4d2a85a5b41f56
Gitweb:     http://git.kernel.org/tip/d2ebc71d472020bc30e29afe8c4d2a85a5b41f56
Author:     Cliff Wickman <cpw@sgi.com>
AuthorDate: Wed, 18 Jan 2012 09:40:47 -0600
Committer:  Ingo Molnar <mingo@elte.hu>
CommitDate: Thu, 26 Jan 2012 10:58:34 +0100

x86/uv: Fix uninitialized spinlocks

Initialize two spinlocks in tlb_uv.c and also properly define/initialize
the uv_irq_lock.

The lack of explicit initialization seems to be functionally
harmless, but it is diagnosed when these are turned on:

        CONFIG_DEBUG_SPINLOCK=y
        CONFIG_DEBUG_MUTEXES=y
        CONFIG_DEBUG_LOCK_ALLOC=y
        CONFIG_LOCKDEP=y

Signed-off-by: Cliff Wickman <cpw@sgi.com>
Cc: <stable@kernel.org>
Cc: Dimitri Sivanich <sivanich@sgi.com>
Link: http://lkml.kernel.org/r/E1RnXd1-0003wU-PM@eag09.americas.sgi.com
[ Added the uv_irq_lock initialization fix by Dimitri Sivanich ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 arch/x86/platform/uv/tlb_uv.c |    2 ++
 arch/x86/platform/uv/uv_irq.c |    2 +-
 2 files changed, 3 insertions(+), 1 deletions(-)

diff --git a/arch/x86/platform/uv/tlb_uv.c b/arch/x86/platform/uv/tlb_uv.c
index 9be4cff..3ae0e61 100644
--- a/arch/x86/platform/uv/tlb_uv.c
+++ b/arch/x86/platform/uv/tlb_uv.c
@@ -1851,6 +1851,8 @@ static void __init init_per_cpu_tunables(void)
 		bcp->cong_reps			= congested_reps;
 		bcp->cong_period		= congested_period;
 		bcp->clocks_per_100_usec =	usec_2_cycles(100);
+		spin_lock_init(&bcp->queue_lock);
+		spin_lock_init(&bcp->uvhub_lock);
 	}
 }
 
diff --git a/arch/x86/platform/uv/uv_irq.c b/arch/x86/platform/uv/uv_irq.c
index 374a05d..f25c276 100644
--- a/arch/x86/platform/uv/uv_irq.c
+++ b/arch/x86/platform/uv/uv_irq.c
@@ -25,7 +25,7 @@ struct uv_irq_2_mmr_pnode{
 	int			irq;
 };
 
-static spinlock_t		uv_irq_lock;
+static DEFINE_SPINLOCK(uv_irq_lock);
 static struct rb_root		uv_irq_root;
 
 static int uv_set_irq_affinity(struct irq_data *, const struct cpumask *, bool);