Peter,
Commit c65c1877bd68 (slub: use lockdep_assert_held) introduced the following
warning on mx5/mx6 systems (ARMv7) running linux-next 20140124:
Virtual kernel memory layout:
vector : 0xffff0000 - 0xffff1000 ( 4 kB)
fixmap : 0xfff00000 - 0xfffe0000 ( 896 kB)
vmalloc : 0xa0800000 - 0xff000000 (1512 MB)
lowmem : 0x80000000 - 0xa0000000 ( 512 MB)
pkmap : 0x7fe00000 - 0x80000000 ( 2 MB)
modules : 0x7f000000 - 0x7fe00000 ( 14 MB)
.text : 0x80008000 - 0x807e0edc (8036 kB)
.init : 0x807e1000 - 0x8082e300 ( 309 kB)
.data : 0x80830000 - 0x8088b900 ( 367 kB)
.bss : 0x8088b908 - 0x80debdb0 (5506 kB)
------------[ cut here ]------------
WARNING: CPU: 0 PID: 0 at mm/slub.c:1511 __kmem_cache_create+0x24c/0x318()
Modules linked in:
CPU: 0 PID: 0 Comm: swapper Not tainted 3.13.0-next-20140124 #685
Backtrace:
[<8001235c>] (dump_backtrace) from [<800124f8>] (show_stack+0x18/0x1c)
r6:800da30c r5:00000009 r4:00000000 r3:00000000
[<800124e0>] (show_stack) from [<805e56d8>] (dump_stack+0x80/0x9c)
[<805e5658>] (dump_stack) from [<80027834>] (warn_slowpath_common+0x70/0x94)
r4:00000000 r3:8083bcf0
[<800277c4>] (warn_slowpath_common) from [<8002787c>] (warn_slowpath_null+0x24/0
x2c)
r8:80dbeb18 r7:00002000 r6:80821c94 r5:9ffd8000 r4:9f000000
[<80027858>] (warn_slowpath_null) from [<800da30c>] (__kmem_cache_create+0x24c/0
x318)
[<800da0c0>] (__kmem_cache_create) from [<80801d34>] (create_boot_cache+0x50/0x7
8)
r10:9fffcb80 r9:412fc085 r8:80838880 r7:80821d08 r6:8073e360 r5:80821c94
r4:0000002c
[<80801ce4>] (create_boot_cache) from [<80803544>] (kmem_cache_init+0x3c/0xe0)
r6:80dbeb14 r5:80821c94 r4:80dc41a4 r3:00002000
[<80803508>] (kmem_cache_init) from [<807e19cc>] (start_kernel+0x198/0x384)
r8:80838880 r7:8081f4c0 r6:ffffffff r5:8088b940 r4:00000001
[<807e1834>] (start_kernel) from [<90008074>] (0x90008074)
r10:00000000 r8:90004059 r7:8083d3ac r6:8081f4bc r5:80838928 r4:10c53c7d
---[ end trace 3406ff24bd97382e ]---
If I revert this commit, the warning goes away.
It also goes away if this only line is removed:
diff --git a/mm/slub.c b/mm/slub.c
index d2388c8..fde5852 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -1508,8 +1508,6 @@ static void discard_slab(struct kmem_cache *s,
struct page *page)
static inline void add_partial(struct kmem_cache_node *n,
struct page *page, int tail)
{
- lockdep_assert_held(&n->list_lock);
-
n->nr_partial++;
if (tail == DEACTIVATE_TO_TAIL)
list_add_tail(&page->lru, &n->partial);
Regards,
Fabio Estevam
On Fri, Jan 24, 2014 at 11:52:37AM -0200, Fabio Estevam wrote:
> Peter,
>
> Commit c65c1877bd68 (slub: use lockdep_assert_held) introduced the following
> warning on mx5/mx6 systems (ARMv7) running linux-next 20140124:
>
> Virtual kernel memory layout:
> vector : 0xffff0000 - 0xffff1000 ( 4 kB)
> fixmap : 0xfff00000 - 0xfffe0000 ( 896 kB)
> vmalloc : 0xa0800000 - 0xff000000 (1512 MB)
> lowmem : 0x80000000 - 0xa0000000 ( 512 MB)
> pkmap : 0x7fe00000 - 0x80000000 ( 2 MB)
> modules : 0x7f000000 - 0x7fe00000 ( 14 MB)
> .text : 0x80008000 - 0x807e0edc (8036 kB)
> .init : 0x807e1000 - 0x8082e300 ( 309 kB)
> .data : 0x80830000 - 0x8088b900 ( 367 kB)
> .bss : 0x8088b908 - 0x80debdb0 (5506 kB)
> ------------[ cut here ]------------
> WARNING: CPU: 0 PID: 0 at mm/slub.c:1511 __kmem_cache_create+0x24c/0x318()
> Modules linked in:
> CPU: 0 PID: 0 Comm: swapper Not tainted 3.13.0-next-20140124 #685
> Backtrace:
> [<8001235c>] (dump_backtrace) from [<800124f8>] (show_stack+0x18/0x1c)
> r6:800da30c r5:00000009 r4:00000000 r3:00000000
> [<800124e0>] (show_stack) from [<805e56d8>] (dump_stack+0x80/0x9c)
> [<805e5658>] (dump_stack) from [<80027834>] (warn_slowpath_common+0x70/0x94)
> r4:00000000 r3:8083bcf0
> [<800277c4>] (warn_slowpath_common) from [<8002787c>] (warn_slowpath_null+0x24/0
> x2c)
> r8:80dbeb18 r7:00002000 r6:80821c94 r5:9ffd8000 r4:9f000000
> [<80027858>] (warn_slowpath_null) from [<800da30c>] (__kmem_cache_create+0x24c/0
> x318)
> [<800da0c0>] (__kmem_cache_create) from [<80801d34>] (create_boot_cache+0x50/0x7
> 8)
> r10:9fffcb80 r9:412fc085 r8:80838880 r7:80821d08 r6:8073e360 r5:80821c94
> r4:0000002c
> [<80801ce4>] (create_boot_cache) from [<80803544>] (kmem_cache_init+0x3c/0xe0)
> r6:80dbeb14 r5:80821c94 r4:80dc41a4 r3:00002000
> [<80803508>] (kmem_cache_init) from [<807e19cc>] (start_kernel+0x198/0x384)
> r8:80838880 r7:8081f4c0 r6:ffffffff r5:8088b940 r4:00000001
> [<807e1834>] (start_kernel) from [<90008074>] (0x90008074)
> r10:00000000 r8:90004059 r7:8083d3ac r6:8081f4bc r5:80838928 r4:10c53c7d
> ---[ end trace 3406ff24bd97382e ]---
>
> If I revert this commit, the warning goes away.
>
> It also goes away if this only line is removed:
>
> diff --git a/mm/slub.c b/mm/slub.c
> index d2388c8..fde5852 100644
> --- a/mm/slub.c
> +++ b/mm/slub.c
> @@ -1508,8 +1508,6 @@ static void discard_slab(struct kmem_cache *s,
> struct page *page)
> static inline void add_partial(struct kmem_cache_node *n,
> struct page *page, int tail)
> {
> - lockdep_assert_held(&n->list_lock);
> -
> n->nr_partial++;
> if (tail == DEACTIVATE_TO_TAIL)
> list_add_tail(&page->lru, &n->partial);
Dave Hansen already send a fix for that:
lkml.kernel.org/r/[email protected]
Pekka, any chance to get that merged?
On Fri, Jan 24, 2014 at 12:21 PM, Peter Zijlstra <[email protected]> wrote:
> Dave Hansen already send a fix for that:
>
> lkml.kernel.org/r/[email protected]
Thanks, Peter. Dave's patch fixes the warning.
Dave,
Do you plan to submit your fix as a formal patch?
Regards,
Fabio Estevam
On 01/24/2014 04:21 PM, Peter Zijlstra wrote:
> Dave Hansen already send a fix for that:
>
> lkml.kernel.org/r/[email protected]
>
>
>
> Pekka, any chance to get that merged?
Sorry for the delay - I'm way behind my inbox.
It's applied now, thanks!
Pekka