[PATCH] Initialise spinlock in the DEBUG_PAGEALLOC code

[PATCH] Initialise spinlock in the DEBUG_PAGEALLOC code

[Michael Ellerman]

Fixes:

BUG: spinlock bad magic on CPU#0, swapper/0
 lock: c00000000064ec30, .magic: 00000000, .owner: <none>/-1, .owner_cpu: 0
Call Trace:
[c00000000062b980] [c00000000000f920] .show_stack+0x6c/0x1a0 (unreliable)
[c00000000062ba20] [c0000000001c2b40] .spin_bug+0xb0/0xd4
[c00000000062bab0] [c0000000001c2ed0] ._raw_spin_lock+0x44/0x184
[c00000000062bb50] [c0000000003a42b4] ._spin_lock+0x10/0x24
[c00000000062bbd0] [c00000000002b4dc] .kernel_map_pages+0x198/0x278
[c00000000062bc90] [c000000000079720] .free_hot_cold_page+0x124/0x418
[c00000000062bd70] [c000000000530278] .free_all_bootmem_core+0x14c/0x224
[c00000000062be50] [c00000000052a178] .mem_init+0x68/0x170
[c00000000062bee0] [c00000000051d874] .start_kernel+0x2a0/0x37c
[c00000000062bf90] [c0000000000084c8] .start_here_common+0x54/0x8c


Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
---

 arch/powerpc/mm/hash_utils_64.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Index: powerpc/arch/powerpc/mm/hash_utils_64.c
===================================================================
--- powerpc.orig/arch/powerpc/mm/hash_utils_64.c
+++ powerpc/arch/powerpc/mm/hash_utils_64.c
@@ -103,7 +103,7 @@ int mmu_ci_restrictions;
 #ifdef CONFIG_DEBUG_PAGEALLOC
 static u8 *linear_map_hash_slots;
 static unsigned long linear_map_hash_count;
-static spinlock_t linear_map_hash_lock;
+static spinlock_t linear_map_hash_lock = SPIN_LOCK_UNLOCKED;
 #endif /* CONFIG_DEBUG_PAGEALLOC */
 
 /* There are definitions of page sizes arrays to be used when none

Re: [PATCH] Initialise spinlock in the DEBUG_PAGEALLOC code

[Milton Miller]

On Tue Apr 17 11:43:12 EST 2007, Michael Ellerman wrote:
> -static spinlock_t linear_map_hash_lock;
> +static spinlock_t linear_map_hash_lock = SPIN_LOCK_UNLOCKED;

I think the people in this thread

[KJ][PATCH]SPIN_LOCK_UNLOCKED cleanup in arch/powerpc
http://ozlabs.org/pipermail/linuxppc-dev/2007-April/034210.html

SPIN_LOCK_UNLOCKED cleanup,use DEFINE_SPINLOCK or
__SPIN_LOCK_UNLOCKED where ever appropriate.

would like you to initialize it differently.  (I think it has
to do with the lock dependancy stuff).

milton

Re: [PATCH] Initialise spinlock in the DEBUG_PAGEALLOC code

[Michael Ellerman]

[-- Attachment #1: Type: text/plain, Size: 936 bytes --]

On Tue, 2007-04-17 at 02:57 -0500, Milton Miller wrote:
> On Tue Apr 17 11:43:12 EST 2007, Michael Ellerman wrote:
> > -static spinlock_t linear_map_hash_lock;
> > +static spinlock_t linear_map_hash_lock = SPIN_LOCK_UNLOCKED;
> 
> I think the people in this thread
> 
> [KJ][PATCH]SPIN_LOCK_UNLOCKED cleanup in arch/powerpc
> http://ozlabs.org/pipermail/linuxppc-dev/2007-April/034210.html
> 
> SPIN_LOCK_UNLOCKED cleanup,use DEFINE_SPINLOCK or
> __SPIN_LOCK_UNLOCKED where ever appropriate.
> 
> would like you to initialize it differently.  (I think it has
> to do with the lock dependancy stuff).

And it's documented where .. ?

I'll send a new patch.

cheers

-- 
Michael Ellerman
OzLabs, IBM Australia Development Lab

wwweb: http://michael.ellerman.id.au
phone: +61 2 6212 1183 (tie line 70 21183)

We do not inherit the earth from our ancestors,
we borrow it from our children. - S.M.A.R.T Person

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[PATCH] Initialise spinlock in the DEBUG_PAGEALLOC code

[Michael Ellerman]

Fixes:

BUG: spinlock bad magic on CPU#0, swapper/0
 lock: c00000000064ec30, .magic: 00000000, .owner: <none>/-1, .owner_cpu: 0
Call Trace:
[c00000000062b980] [c00000000000f920] .show_stack+0x6c/0x1a0 (unreliable)
[c00000000062ba20] [c0000000001c2b40] .spin_bug+0xb0/0xd4
[c00000000062bab0] [c0000000001c2ed0] ._raw_spin_lock+0x44/0x184
[c00000000062bb50] [c0000000003a42b4] ._spin_lock+0x10/0x24
[c00000000062bbd0] [c00000000002b4dc] .kernel_map_pages+0x198/0x278
[c00000000062bc90] [c000000000079720] .free_hot_cold_page+0x124/0x418
[c00000000062bd70] [c000000000530278] .free_all_bootmem_core+0x14c/0x224
[c00000000062be50] [c00000000052a178] .mem_init+0x68/0x170
[c00000000062bee0] [c00000000051d874] .start_kernel+0x2a0/0x37c
[c00000000062bf90] [c0000000000084c8] .start_here_common+0x54/0x8c


Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
---

 arch/powerpc/mm/hash_utils_64.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Index: powerpc/arch/powerpc/mm/hash_utils_64.c
===================================================================
--- powerpc.orig/arch/powerpc/mm/hash_utils_64.c
+++ powerpc/arch/powerpc/mm/hash_utils_64.c
@@ -103,7 +103,7 @@ int mmu_ci_restrictions;
 #ifdef CONFIG_DEBUG_PAGEALLOC
 static u8 *linear_map_hash_slots;
 static unsigned long linear_map_hash_count;
-static spinlock_t linear_map_hash_lock;
+static DEFINE_SPINLOCK(linear_map_hash_lock);
 #endif /* CONFIG_DEBUG_PAGEALLOC */
 
 /* There are definitions of page sizes arrays to be used when none