Re: [PATCH] cpufreq_stats: fix race between stats allocation and first usage
On Saturday, December 15, 2012 11:01:49 AM Konstantin Khlebnikov wrote: > Rafael J. Wysocki wrote: > > On Friday, December 14, 2012 02:59:21 PM Konstantin Khlebnikov wrote: > >> This patch forces complete struct cpufreq_stats allocation for all cpus > >> before > >> registering CPUFREQ_TRANSITION_NOTIFIER notifier, otherwise in some > >> conditions > >> cpufreq_stat_notifier_trans() can be called in the middle of stats > >> allocation, > >> in this case cpufreq_stats_table already exists, but stat->freq_table is > >> NULL. > > > > I'll queue it up for submission as v3.8 material. > > > > Does it need to be marked as -stable material too? > > It's very old and rare bug. I think you can leave it as is. OK Thanks, Rafael -- I speak only for myself. Rafael J. Wysocki, Intel Open Source Technology Center. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] cpufreq_stats: fix race between stats allocation and first usage
On Saturday, December 15, 2012 11:01:49 AM Konstantin Khlebnikov wrote: Rafael J. Wysocki wrote: On Friday, December 14, 2012 02:59:21 PM Konstantin Khlebnikov wrote: This patch forces complete struct cpufreq_stats allocation for all cpus before registering CPUFREQ_TRANSITION_NOTIFIER notifier, otherwise in some conditions cpufreq_stat_notifier_trans() can be called in the middle of stats allocation, in this case cpufreq_stats_table already exists, but stat-freq_table is NULL. I'll queue it up for submission as v3.8 material. Does it need to be marked as -stable material too? It's very old and rare bug. I think you can leave it as is. OK Thanks, Rafael -- I speak only for myself. Rafael J. Wysocki, Intel Open Source Technology Center. -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] cpufreq_stats: fix race between stats allocation and first usage
Rafael J. Wysocki wrote:
On Friday, December 14, 2012 02:59:21 PM Konstantin Khlebnikov wrote:
This patch forces complete struct cpufreq_stats allocation for all cpus before
registering CPUFREQ_TRANSITION_NOTIFIER notifier, otherwise in some conditions
cpufreq_stat_notifier_trans() can be called in the middle of stats allocation,
in this case cpufreq_stats_table already exists, but stat->freq_table is NULL.
I'll queue it up for submission as v3.8 material.
Does it need to be marked as -stable material too?
It's very old and rare bug. I think you can leave it as is.
Rafael
Signed-off-by: Konstantin Khlebnikov
Cc: Rafael J. Wysocki
Cc: cpufreq
Cc: linux-pm
---
<1>[ 363.116198] BUG: unable to handle kernel NULL pointer dereference at
(null)
<1>[ 363.116668] IP: []
cpufreq_stat_notifier_trans+0x64/0xf0 [cpufreq_stats]
<4>[ 363.116977] PGD 23177e067 PUD 2349c1067 PMD 0
<4>[ 363.117151] Oops: [#1] SMP
<4>[ 363.117151] last sysfs file: /sys/module/freq_table/initstate
<4>[ 363.117151] CPU 5
<4>[ 363.117151] Modules linked in: cpufreq_stats(+)(U) [a lot] [last
unloaded: umc]
<4>[ 363.117151]
<4>[ 363.117151] Pid: 1690, comm: kondemand/5 veid: 0 Tainted: PWC
--- T 2.6.32-279.5.1.el6-042stab061.7-vz #112 042stab061_7 System
manufacturer System Product Name/Crosshair IV Formula
<4>[ 363.117151] RIP: 0010:[] []
cpufreq_stat_notifier_trans+0x64/0xf0 [cpufreq_stats]
<4>[ 363.117151] RSP: 0018:880234281920 EFLAGS: 00010246
<4>[ 363.117151] RAX: 001e12e8 RBX: RCX:
002ab980
<4>[ 363.117151] RDX: 0004 RSI: RDI:
0005
<4>[ 363.117151] RBP: 880234281940 R08: R09:
<4>[ 363.117151] R10: R11: R12:
880218ce7400
<4>[ 363.117151] R13: R14: R15:
<4>[ 363.117151] FS: 7f499ffe0700() GS:88003100()
knlGS:
<4>[ 363.117151] CS: 0010 DS: 0018 ES: 0018 CR0: 8005003b
<4>[ 363.117151] CR2: CR3: 000230af7000 CR4:
06e0
<4>[ 363.117151] DR0: DR1: DR2:
<4>[ 363.117151] DR3: DR6: 0ff0 DR7:
0400
<4>[ 363.117151] Process kondemand/5 (pid: 1690, veid: 0, threadinfo
88023428, task 8802330c48c0)
<4>[ 363.117151] Stack:
<4>[ 363.117151] 810cf4f3 0001
a11a7ac0
<4>[ 363.117151] 880234281990 815454a8 880234281c80
<4>[ 363.117151] 880234281a10 833be978 833be8e0
0001
<4>[ 363.117151] Call Trace:
<4>[ 363.117151] [] ? is_module_text_address+0x23/0x30
<4>[ 363.117151] [] notifier_call_chain+0x58/0xb0
<4>[ 363.117151] [] __srcu_notifier_call_chain+0x5d/0x90
<4>[ 363.117151] [] srcu_notifier_call_chain+0x16/0x20
<4>[ 363.117151] [] cpufreq_notify_transition+0x12a/0x190
<4>[ 363.117151] [] powernowk8_target+0x628/0xb30
[powernow_k8]
<4>[ 363.117151] [] __cpufreq_driver_target+0x8b/0x90
<4>[ 363.117151] [] do_dbs_timer+0x3b8/0x3bc
[cpufreq_ondemand]
<4>[ 363.117151] [] ? do_dbs_timer+0x0/0x3bc
[cpufreq_ondemand]
<4>[ 363.117151] [] worker_thread+0x264/0x440
<4>[ 363.117151] [] ? worker_thread+0x213/0x440
<4>[ 363.117151] [] ? worker_thread+0x0/0x440
<4>[ 363.117151] [] ? autoremove_wake_function+0x0/0x40
<4>[ 363.117151] [] ? worker_thread+0x0/0x440
<4>[ 363.117151] [] kthread+0x96/0xa0
<4>[ 363.117151] [] child_rip+0xa/0x20
<4>[ 363.117151] [] ? restore_args+0x0/0x30
<4>[ 363.117151] [] ? kthread+0x0/0xa0
<4>[ 363.117151] [] ? child_rip+0x0/0x20
<4>[ 363.117151] Code: 89 f9 48 8b 0c cd 20 53 9c 81 4c 8b 24 08 4d 85 e4 74 d3 8b
4a 08 41 8b 54 24 10 45 8b 6c 24 18 85 d2 74 22 49 8b 74 24 28 31 db<3b> 0e 75 10 eb
1a 66 0f 1f 44 00 00 48 63 c3 3b 0c 86 74 0c 83
<1>[ 363.117151] RIP []
cpufreq_stat_notifier_trans+0x64/0xf0 [cpufreq_stats]
<4>[ 363.117151] RSP
<4>[ 363.117151] CR2:
---
drivers/cpufreq/cpufreq_stats.c | 11 +++
1 file changed, 7 insertions(+), 4 deletions(-)
diff --git a/drivers/cpufreq/cpufreq_stats.c b/drivers/cpufreq/cpufreq_stats.c
index e40e508..9d7732b 100644
--- a/drivers/cpufreq/cpufreq_stats.c
+++ b/drivers/cpufreq/cpufreq_stats.c
@@ -364,18 +364,21 @@ static int __init cpufreq_stats_init(void)
if (ret)
return ret;
+ register_hotcpu_notifier(_stat_cpu_notifier);
+ for_each_online_cpu(cpu)
+ cpufreq_update_policy(cpu);
+
ret = cpufreq_register_notifier(_trans_block,
CPUFREQ_TRANSITION_NOTIFIER);
if (ret) {
cpufreq_unregister_notifier(_policy_block,
CPUFREQ_POLICY_NOTIFIER);
+ unregister_hotcpu_notifier(_stat_cpu_notifier);
+
Re: [PATCH] cpufreq_stats: fix race between stats allocation and first usage
On Friday, December 14, 2012 02:59:21 PM Konstantin Khlebnikov wrote:
> This patch forces complete struct cpufreq_stats allocation for all cpus before
> registering CPUFREQ_TRANSITION_NOTIFIER notifier, otherwise in some conditions
> cpufreq_stat_notifier_trans() can be called in the middle of stats allocation,
> in this case cpufreq_stats_table already exists, but stat->freq_table is NULL.
I'll queue it up for submission as v3.8 material.
Does it need to be marked as -stable material too?
Rafael
> Signed-off-by: Konstantin Khlebnikov
> Cc: Rafael J. Wysocki
> Cc: cpufreq
> Cc: linux-pm
>
> ---
>
> <1>[ 363.116198] BUG: unable to handle kernel NULL pointer dereference at
> (null)
> <1>[ 363.116668] IP: []
> cpufreq_stat_notifier_trans+0x64/0xf0 [cpufreq_stats]
> <4>[ 363.116977] PGD 23177e067 PUD 2349c1067 PMD 0
> <4>[ 363.117151] Oops: [#1] SMP
> <4>[ 363.117151] last sysfs file: /sys/module/freq_table/initstate
> <4>[ 363.117151] CPU 5
> <4>[ 363.117151] Modules linked in: cpufreq_stats(+)(U) [a lot] [last
> unloaded: umc]
> <4>[ 363.117151]
> <4>[ 363.117151] Pid: 1690, comm: kondemand/5 veid: 0 Tainted: PWC
> --- T 2.6.32-279.5.1.el6-042stab061.7-vz #112 042stab061_7
> System manufacturer System Product Name/Crosshair IV Formula
> <4>[ 363.117151] RIP: 0010:[] []
> cpufreq_stat_notifier_trans+0x64/0xf0 [cpufreq_stats]
> <4>[ 363.117151] RSP: 0018:880234281920 EFLAGS: 00010246
> <4>[ 363.117151] RAX: 001e12e8 RBX: RCX:
> 002ab980
> <4>[ 363.117151] RDX: 0004 RSI: RDI:
> 0005
> <4>[ 363.117151] RBP: 880234281940 R08: R09:
>
> <4>[ 363.117151] R10: R11: R12:
> 880218ce7400
> <4>[ 363.117151] R13: R14: R15:
>
> <4>[ 363.117151] FS: 7f499ffe0700() GS:88003100()
> knlGS:
> <4>[ 363.117151] CS: 0010 DS: 0018 ES: 0018 CR0: 8005003b
> <4>[ 363.117151] CR2: CR3: 000230af7000 CR4:
> 06e0
> <4>[ 363.117151] DR0: DR1: DR2:
>
> <4>[ 363.117151] DR3: DR6: 0ff0 DR7:
> 0400
> <4>[ 363.117151] Process kondemand/5 (pid: 1690, veid: 0, threadinfo
> 88023428, task 8802330c48c0)
> <4>[ 363.117151] Stack:
> <4>[ 363.117151] 810cf4f3 0001
> a11a7ac0
> <4>[ 363.117151] 880234281990 815454a8 880234281c80
>
> <4>[ 363.117151] 880234281a10 833be978 833be8e0
> 0001
> <4>[ 363.117151] Call Trace:
> <4>[ 363.117151] [] ? is_module_text_address+0x23/0x30
> <4>[ 363.117151] [] notifier_call_chain+0x58/0xb0
> <4>[ 363.117151] [] __srcu_notifier_call_chain+0x5d/0x90
> <4>[ 363.117151] [] srcu_notifier_call_chain+0x16/0x20
> <4>[ 363.117151] [] cpufreq_notify_transition+0x12a/0x190
> <4>[ 363.117151] [] powernowk8_target+0x628/0xb30
> [powernow_k8]
> <4>[ 363.117151] [] __cpufreq_driver_target+0x8b/0x90
> <4>[ 363.117151] [] do_dbs_timer+0x3b8/0x3bc
> [cpufreq_ondemand]
> <4>[ 363.117151] [] ? do_dbs_timer+0x0/0x3bc
> [cpufreq_ondemand]
> <4>[ 363.117151] [] worker_thread+0x264/0x440
> <4>[ 363.117151] [] ? worker_thread+0x213/0x440
> <4>[ 363.117151] [] ? worker_thread+0x0/0x440
> <4>[ 363.117151] [] ? autoremove_wake_function+0x0/0x40
> <4>[ 363.117151] [] ? worker_thread+0x0/0x440
> <4>[ 363.117151] [] kthread+0x96/0xa0
> <4>[ 363.117151] [] child_rip+0xa/0x20
> <4>[ 363.117151] [] ? restore_args+0x0/0x30
> <4>[ 363.117151] [] ? kthread+0x0/0xa0
> <4>[ 363.117151] [] ? child_rip+0x0/0x20
> <4>[ 363.117151] Code: 89 f9 48 8b 0c cd 20 53 9c 81 4c 8b 24 08 4d 85 e4 74
> d3 8b 4a 08 41 8b 54 24 10 45 8b 6c 24 18 85 d2 74 22 49 8b 74 24 28 31 db
> <3b> 0e 75 10 eb 1a 66 0f 1f 44 00 00 48 63 c3 3b 0c 86 74 0c 83
> <1>[ 363.117151] RIP []
> cpufreq_stat_notifier_trans+0x64/0xf0 [cpufreq_stats]
> <4>[ 363.117151] RSP
> <4>[ 363.117151] CR2:
> ---
> drivers/cpufreq/cpufreq_stats.c | 11 +++
> 1 file changed, 7 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/cpufreq/cpufreq_stats.c b/drivers/cpufreq/cpufreq_stats.c
> index e40e508..9d7732b 100644
> --- a/drivers/cpufreq/cpufreq_stats.c
> +++ b/drivers/cpufreq/cpufreq_stats.c
> @@ -364,18 +364,21 @@ static int __init cpufreq_stats_init(void)
> if (ret)
> return ret;
>
> + register_hotcpu_notifier(_stat_cpu_notifier);
> + for_each_online_cpu(cpu)
> + cpufreq_update_policy(cpu);
> +
> ret = cpufreq_register_notifier(_trans_block,
> CPUFREQ_TRANSITION_NOTIFIER);
> if (ret) {
> cpufreq_unregister_notifier(_policy_block,
>
[PATCH] cpufreq_stats: fix race between stats allocation and first usage
This patch forces complete struct cpufreq_stats allocation for all cpus before
registering CPUFREQ_TRANSITION_NOTIFIER notifier, otherwise in some conditions
cpufreq_stat_notifier_trans() can be called in the middle of stats allocation,
in this case cpufreq_stats_table already exists, but stat->freq_table is NULL.
Signed-off-by: Konstantin Khlebnikov
Cc: Rafael J. Wysocki
Cc: cpufreq
Cc: linux-pm
---
<1>[ 363.116198] BUG: unable to handle kernel NULL pointer dereference at
(null)
<1>[ 363.116668] IP: []
cpufreq_stat_notifier_trans+0x64/0xf0 [cpufreq_stats]
<4>[ 363.116977] PGD 23177e067 PUD 2349c1067 PMD 0
<4>[ 363.117151] Oops: [#1] SMP
<4>[ 363.117151] last sysfs file: /sys/module/freq_table/initstate
<4>[ 363.117151] CPU 5
<4>[ 363.117151] Modules linked in: cpufreq_stats(+)(U) [a lot] [last
unloaded: umc]
<4>[ 363.117151]
<4>[ 363.117151] Pid: 1690, comm: kondemand/5 veid: 0 Tainted: PWC
--- T 2.6.32-279.5.1.el6-042stab061.7-vz #112 042stab061_7 System
manufacturer System Product Name/Crosshair IV Formula
<4>[ 363.117151] RIP: 0010:[] []
cpufreq_stat_notifier_trans+0x64/0xf0 [cpufreq_stats]
<4>[ 363.117151] RSP: 0018:880234281920 EFLAGS: 00010246
<4>[ 363.117151] RAX: 001e12e8 RBX: RCX:
002ab980
<4>[ 363.117151] RDX: 0004 RSI: RDI:
0005
<4>[ 363.117151] RBP: 880234281940 R08: R09:
<4>[ 363.117151] R10: R11: R12:
880218ce7400
<4>[ 363.117151] R13: R14: R15:
<4>[ 363.117151] FS: 7f499ffe0700() GS:88003100()
knlGS:
<4>[ 363.117151] CS: 0010 DS: 0018 ES: 0018 CR0: 8005003b
<4>[ 363.117151] CR2: CR3: 000230af7000 CR4:
06e0
<4>[ 363.117151] DR0: DR1: DR2:
<4>[ 363.117151] DR3: DR6: 0ff0 DR7:
0400
<4>[ 363.117151] Process kondemand/5 (pid: 1690, veid: 0, threadinfo
88023428, task 8802330c48c0)
<4>[ 363.117151] Stack:
<4>[ 363.117151] 810cf4f3 0001
a11a7ac0
<4>[ 363.117151] 880234281990 815454a8 880234281c80
<4>[ 363.117151] 880234281a10 833be978 833be8e0
0001
<4>[ 363.117151] Call Trace:
<4>[ 363.117151] [] ? is_module_text_address+0x23/0x30
<4>[ 363.117151] [] notifier_call_chain+0x58/0xb0
<4>[ 363.117151] [] __srcu_notifier_call_chain+0x5d/0x90
<4>[ 363.117151] [] srcu_notifier_call_chain+0x16/0x20
<4>[ 363.117151] [] cpufreq_notify_transition+0x12a/0x190
<4>[ 363.117151] [] powernowk8_target+0x628/0xb30
[powernow_k8]
<4>[ 363.117151] [] __cpufreq_driver_target+0x8b/0x90
<4>[ 363.117151] [] do_dbs_timer+0x3b8/0x3bc
[cpufreq_ondemand]
<4>[ 363.117151] [] ? do_dbs_timer+0x0/0x3bc
[cpufreq_ondemand]
<4>[ 363.117151] [] worker_thread+0x264/0x440
<4>[ 363.117151] [] ? worker_thread+0x213/0x440
<4>[ 363.117151] [] ? worker_thread+0x0/0x440
<4>[ 363.117151] [] ? autoremove_wake_function+0x0/0x40
<4>[ 363.117151] [] ? worker_thread+0x0/0x440
<4>[ 363.117151] [] kthread+0x96/0xa0
<4>[ 363.117151] [] child_rip+0xa/0x20
<4>[ 363.117151] [] ? restore_args+0x0/0x30
<4>[ 363.117151] [] ? kthread+0x0/0xa0
<4>[ 363.117151] [] ? child_rip+0x0/0x20
<4>[ 363.117151] Code: 89 f9 48 8b 0c cd 20 53 9c 81 4c 8b 24 08 4d 85 e4 74
d3 8b 4a 08 41 8b 54 24 10 45 8b 6c 24 18 85 d2 74 22 49 8b 74 24 28 31 db <3b>
0e 75 10 eb 1a 66 0f 1f 44 00 00 48 63 c3 3b 0c 86 74 0c 83
<1>[ 363.117151] RIP []
cpufreq_stat_notifier_trans+0x64/0xf0 [cpufreq_stats]
<4>[ 363.117151] RSP
<4>[ 363.117151] CR2:
---
drivers/cpufreq/cpufreq_stats.c | 11 +++
1 file changed, 7 insertions(+), 4 deletions(-)
diff --git a/drivers/cpufreq/cpufreq_stats.c b/drivers/cpufreq/cpufreq_stats.c
index e40e508..9d7732b 100644
--- a/drivers/cpufreq/cpufreq_stats.c
+++ b/drivers/cpufreq/cpufreq_stats.c
@@ -364,18 +364,21 @@ static int __init cpufreq_stats_init(void)
if (ret)
return ret;
+ register_hotcpu_notifier(_stat_cpu_notifier);
+ for_each_online_cpu(cpu)
+ cpufreq_update_policy(cpu);
+
ret = cpufreq_register_notifier(_trans_block,
CPUFREQ_TRANSITION_NOTIFIER);
if (ret) {
cpufreq_unregister_notifier(_policy_block,
CPUFREQ_POLICY_NOTIFIER);
+ unregister_hotcpu_notifier(_stat_cpu_notifier);
+ for_each_online_cpu(cpu)
+ cpufreq_stats_free_table(cpu);
return ret;
}
- register_hotcpu_notifier(_stat_cpu_notifier);
- for_each_online_cpu(cpu) {
- cpufreq_update_policy(cpu);
-
[PATCH] cpufreq_stats: fix race between stats allocation and first usage
This patch forces complete struct cpufreq_stats allocation for all cpus before
registering CPUFREQ_TRANSITION_NOTIFIER notifier, otherwise in some conditions
cpufreq_stat_notifier_trans() can be called in the middle of stats allocation,
in this case cpufreq_stats_table already exists, but stat-freq_table is NULL.
Signed-off-by: Konstantin Khlebnikov khlebni...@openvz.org
Cc: Rafael J. Wysocki r...@sisk.pl
Cc: cpufreq cpuf...@vger.kernel.org
Cc: linux-pm linux...@vger.kernel.org
---
1[ 363.116198] BUG: unable to handle kernel NULL pointer dereference at
(null)
1[ 363.116668] IP: [a11a70e4]
cpufreq_stat_notifier_trans+0x64/0xf0 [cpufreq_stats]
4[ 363.116977] PGD 23177e067 PUD 2349c1067 PMD 0
4[ 363.117151] Oops: [#1] SMP
4[ 363.117151] last sysfs file: /sys/module/freq_table/initstate
4[ 363.117151] CPU 5
4[ 363.117151] Modules linked in: cpufreq_stats(+)(U) [a lot] [last
unloaded: umc]
4[ 363.117151]
4[ 363.117151] Pid: 1690, comm: kondemand/5 veid: 0 Tainted: PWC
--- T 2.6.32-279.5.1.el6-042stab061.7-vz #112 042stab061_7 System
manufacturer System Product Name/Crosshair IV Formula
4[ 363.117151] RIP: 0010:[a11a70e4] [a11a70e4]
cpufreq_stat_notifier_trans+0x64/0xf0 [cpufreq_stats]
4[ 363.117151] RSP: 0018:880234281920 EFLAGS: 00010246
4[ 363.117151] RAX: 001e12e8 RBX: RCX:
002ab980
4[ 363.117151] RDX: 0004 RSI: RDI:
0005
4[ 363.117151] RBP: 880234281940 R08: R09:
4[ 363.117151] R10: R11: R12:
880218ce7400
4[ 363.117151] R13: R14: R15:
4[ 363.117151] FS: 7f499ffe0700() GS:88003100()
knlGS:
4[ 363.117151] CS: 0010 DS: 0018 ES: 0018 CR0: 8005003b
4[ 363.117151] CR2: CR3: 000230af7000 CR4:
06e0
4[ 363.117151] DR0: DR1: DR2:
4[ 363.117151] DR3: DR6: 0ff0 DR7:
0400
4[ 363.117151] Process kondemand/5 (pid: 1690, veid: 0, threadinfo
88023428, task 8802330c48c0)
4[ 363.117151] Stack:
4[ 363.117151] 810cf4f3 0001
a11a7ac0
4[ 363.117151] d 880234281990 815454a8 880234281c80
4[ 363.117151] d 880234281a10 833be978 833be8e0
0001
4[ 363.117151] Call Trace:
4[ 363.117151] [810cf4f3] ? is_module_text_address+0x23/0x30
4[ 363.117151] [815454a8] notifier_call_chain+0x58/0xb0
4[ 363.117151] [810a5a8d] __srcu_notifier_call_chain+0x5d/0x90
4[ 363.117151] [810a5ad6] srcu_notifier_call_chain+0x16/0x20
4[ 363.117151] [81442a0a] cpufreq_notify_transition+0x12a/0x190
4[ 363.117151] [a026df08] powernowk8_target+0x628/0xb30
[powernow_k8]
4[ 363.117151] [8144289b] __cpufreq_driver_target+0x8b/0x90
4[ 363.117151] [a0279388] do_dbs_timer+0x3b8/0x3bc
[cpufreq_ondemand]
4[ 363.117151] [a0278fd0] ? do_dbs_timer+0x0/0x3bc
[cpufreq_ondemand]
4[ 363.117151] [81097df4] worker_thread+0x264/0x440
4[ 363.117151] [81097da3] ? worker_thread+0x213/0x440
4[ 363.117151] [81097b90] ? worker_thread+0x0/0x440
4[ 363.117151] [8109f050] ? autoremove_wake_function+0x0/0x40
4[ 363.117151] [81097b90] ? worker_thread+0x0/0x440
4[ 363.117151] [8109e986] kthread+0x96/0xa0
4[ 363.117151] [8100c34a] child_rip+0xa/0x20
4[ 363.117151] [8100bc90] ? restore_args+0x0/0x30
4[ 363.117151] [8109e8f0] ? kthread+0x0/0xa0
4[ 363.117151] [8100c340] ? child_rip+0x0/0x20
4[ 363.117151] Code: 89 f9 48 8b 0c cd 20 53 9c 81 4c 8b 24 08 4d 85 e4 74
d3 8b 4a 08 41 8b 54 24 10 45 8b 6c 24 18 85 d2 74 22 49 8b 74 24 28 31 db 3b
0e 75 10 eb 1a 66 0f 1f 44 00 00 48 63 c3 3b 0c 86 74 0c 83
1[ 363.117151] RIP [a11a70e4]
cpufreq_stat_notifier_trans+0x64/0xf0 [cpufreq_stats]
4[ 363.117151] RSP 880234281920
4[ 363.117151] CR2:
---
drivers/cpufreq/cpufreq_stats.c | 11 +++
1 file changed, 7 insertions(+), 4 deletions(-)
diff --git a/drivers/cpufreq/cpufreq_stats.c b/drivers/cpufreq/cpufreq_stats.c
index e40e508..9d7732b 100644
--- a/drivers/cpufreq/cpufreq_stats.c
+++ b/drivers/cpufreq/cpufreq_stats.c
@@ -364,18 +364,21 @@ static int __init cpufreq_stats_init(void)
if (ret)
return ret;
+ register_hotcpu_notifier(cpufreq_stat_cpu_notifier);
+ for_each_online_cpu(cpu)
+ cpufreq_update_policy(cpu);
+
ret = cpufreq_register_notifier(notifier_trans_block,
CPUFREQ_TRANSITION_NOTIFIER);
if (ret) {
cpufreq_unregister_notifier(notifier_policy_block,
Re: [PATCH] cpufreq_stats: fix race between stats allocation and first usage
On Friday, December 14, 2012 02:59:21 PM Konstantin Khlebnikov wrote: This patch forces complete struct cpufreq_stats allocation for all cpus before registering CPUFREQ_TRANSITION_NOTIFIER notifier, otherwise in some conditions cpufreq_stat_notifier_trans() can be called in the middle of stats allocation, in this case cpufreq_stats_table already exists, but stat-freq_table is NULL. I'll queue it up for submission as v3.8 material. Does it need to be marked as -stable material too? Rafael Signed-off-by: Konstantin Khlebnikov khlebni...@openvz.org Cc: Rafael J. Wysocki r...@sisk.pl Cc: cpufreq cpuf...@vger.kernel.org Cc: linux-pm linux...@vger.kernel.org --- 1[ 363.116198] BUG: unable to handle kernel NULL pointer dereference at (null) 1[ 363.116668] IP: [a11a70e4] cpufreq_stat_notifier_trans+0x64/0xf0 [cpufreq_stats] 4[ 363.116977] PGD 23177e067 PUD 2349c1067 PMD 0 4[ 363.117151] Oops: [#1] SMP 4[ 363.117151] last sysfs file: /sys/module/freq_table/initstate 4[ 363.117151] CPU 5 4[ 363.117151] Modules linked in: cpufreq_stats(+)(U) [a lot] [last unloaded: umc] 4[ 363.117151] 4[ 363.117151] Pid: 1690, comm: kondemand/5 veid: 0 Tainted: PWC --- T 2.6.32-279.5.1.el6-042stab061.7-vz #112 042stab061_7 System manufacturer System Product Name/Crosshair IV Formula 4[ 363.117151] RIP: 0010:[a11a70e4] [a11a70e4] cpufreq_stat_notifier_trans+0x64/0xf0 [cpufreq_stats] 4[ 363.117151] RSP: 0018:880234281920 EFLAGS: 00010246 4[ 363.117151] RAX: 001e12e8 RBX: RCX: 002ab980 4[ 363.117151] RDX: 0004 RSI: RDI: 0005 4[ 363.117151] RBP: 880234281940 R08: R09: 4[ 363.117151] R10: R11: R12: 880218ce7400 4[ 363.117151] R13: R14: R15: 4[ 363.117151] FS: 7f499ffe0700() GS:88003100() knlGS: 4[ 363.117151] CS: 0010 DS: 0018 ES: 0018 CR0: 8005003b 4[ 363.117151] CR2: CR3: 000230af7000 CR4: 06e0 4[ 363.117151] DR0: DR1: DR2: 4[ 363.117151] DR3: DR6: 0ff0 DR7: 0400 4[ 363.117151] Process kondemand/5 (pid: 1690, veid: 0, threadinfo 88023428, task 8802330c48c0) 4[ 363.117151] Stack: 4[ 363.117151] 810cf4f3 0001 a11a7ac0 4[ 363.117151] d 880234281990 815454a8 880234281c80 4[ 363.117151] d 880234281a10 833be978 833be8e0 0001 4[ 363.117151] Call Trace: 4[ 363.117151] [810cf4f3] ? is_module_text_address+0x23/0x30 4[ 363.117151] [815454a8] notifier_call_chain+0x58/0xb0 4[ 363.117151] [810a5a8d] __srcu_notifier_call_chain+0x5d/0x90 4[ 363.117151] [810a5ad6] srcu_notifier_call_chain+0x16/0x20 4[ 363.117151] [81442a0a] cpufreq_notify_transition+0x12a/0x190 4[ 363.117151] [a026df08] powernowk8_target+0x628/0xb30 [powernow_k8] 4[ 363.117151] [8144289b] __cpufreq_driver_target+0x8b/0x90 4[ 363.117151] [a0279388] do_dbs_timer+0x3b8/0x3bc [cpufreq_ondemand] 4[ 363.117151] [a0278fd0] ? do_dbs_timer+0x0/0x3bc [cpufreq_ondemand] 4[ 363.117151] [81097df4] worker_thread+0x264/0x440 4[ 363.117151] [81097da3] ? worker_thread+0x213/0x440 4[ 363.117151] [81097b90] ? worker_thread+0x0/0x440 4[ 363.117151] [8109f050] ? autoremove_wake_function+0x0/0x40 4[ 363.117151] [81097b90] ? worker_thread+0x0/0x440 4[ 363.117151] [8109e986] kthread+0x96/0xa0 4[ 363.117151] [8100c34a] child_rip+0xa/0x20 4[ 363.117151] [8100bc90] ? restore_args+0x0/0x30 4[ 363.117151] [8109e8f0] ? kthread+0x0/0xa0 4[ 363.117151] [8100c340] ? child_rip+0x0/0x20 4[ 363.117151] Code: 89 f9 48 8b 0c cd 20 53 9c 81 4c 8b 24 08 4d 85 e4 74 d3 8b 4a 08 41 8b 54 24 10 45 8b 6c 24 18 85 d2 74 22 49 8b 74 24 28 31 db 3b 0e 75 10 eb 1a 66 0f 1f 44 00 00 48 63 c3 3b 0c 86 74 0c 83 1[ 363.117151] RIP [a11a70e4] cpufreq_stat_notifier_trans+0x64/0xf0 [cpufreq_stats] 4[ 363.117151] RSP 880234281920 4[ 363.117151] CR2: --- drivers/cpufreq/cpufreq_stats.c | 11 +++ 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/drivers/cpufreq/cpufreq_stats.c b/drivers/cpufreq/cpufreq_stats.c index e40e508..9d7732b 100644 --- a/drivers/cpufreq/cpufreq_stats.c +++ b/drivers/cpufreq/cpufreq_stats.c @@ -364,18 +364,21 @@ static int __init cpufreq_stats_init(void) if (ret) return ret; + register_hotcpu_notifier(cpufreq_stat_cpu_notifier); +
Re: [PATCH] cpufreq_stats: fix race between stats allocation and first usage
Rafael J. Wysocki wrote: On Friday, December 14, 2012 02:59:21 PM Konstantin Khlebnikov wrote: This patch forces complete struct cpufreq_stats allocation for all cpus before registering CPUFREQ_TRANSITION_NOTIFIER notifier, otherwise in some conditions cpufreq_stat_notifier_trans() can be called in the middle of stats allocation, in this case cpufreq_stats_table already exists, but stat-freq_table is NULL. I'll queue it up for submission as v3.8 material. Does it need to be marked as -stable material too? It's very old and rare bug. I think you can leave it as is. Rafael Signed-off-by: Konstantin Khlebnikovkhlebni...@openvz.org Cc: Rafael J. Wysockir...@sisk.pl Cc: cpufreqcpuf...@vger.kernel.org Cc: linux-pmlinux...@vger.kernel.org --- 1[ 363.116198] BUG: unable to handle kernel NULL pointer dereference at (null) 1[ 363.116668] IP: [a11a70e4] cpufreq_stat_notifier_trans+0x64/0xf0 [cpufreq_stats] 4[ 363.116977] PGD 23177e067 PUD 2349c1067 PMD 0 4[ 363.117151] Oops: [#1] SMP 4[ 363.117151] last sysfs file: /sys/module/freq_table/initstate 4[ 363.117151] CPU 5 4[ 363.117151] Modules linked in: cpufreq_stats(+)(U) [a lot] [last unloaded: umc] 4[ 363.117151] 4[ 363.117151] Pid: 1690, comm: kondemand/5 veid: 0 Tainted: PWC --- T 2.6.32-279.5.1.el6-042stab061.7-vz #112 042stab061_7 System manufacturer System Product Name/Crosshair IV Formula 4[ 363.117151] RIP: 0010:[a11a70e4] [a11a70e4] cpufreq_stat_notifier_trans+0x64/0xf0 [cpufreq_stats] 4[ 363.117151] RSP: 0018:880234281920 EFLAGS: 00010246 4[ 363.117151] RAX: 001e12e8 RBX: RCX: 002ab980 4[ 363.117151] RDX: 0004 RSI: RDI: 0005 4[ 363.117151] RBP: 880234281940 R08: R09: 4[ 363.117151] R10: R11: R12: 880218ce7400 4[ 363.117151] R13: R14: R15: 4[ 363.117151] FS: 7f499ffe0700() GS:88003100() knlGS: 4[ 363.117151] CS: 0010 DS: 0018 ES: 0018 CR0: 8005003b 4[ 363.117151] CR2: CR3: 000230af7000 CR4: 06e0 4[ 363.117151] DR0: DR1: DR2: 4[ 363.117151] DR3: DR6: 0ff0 DR7: 0400 4[ 363.117151] Process kondemand/5 (pid: 1690, veid: 0, threadinfo 88023428, task 8802330c48c0) 4[ 363.117151] Stack: 4[ 363.117151] 810cf4f3 0001 a11a7ac0 4[ 363.117151]d 880234281990 815454a8 880234281c80 4[ 363.117151]d 880234281a10 833be978 833be8e0 0001 4[ 363.117151] Call Trace: 4[ 363.117151] [810cf4f3] ? is_module_text_address+0x23/0x30 4[ 363.117151] [815454a8] notifier_call_chain+0x58/0xb0 4[ 363.117151] [810a5a8d] __srcu_notifier_call_chain+0x5d/0x90 4[ 363.117151] [810a5ad6] srcu_notifier_call_chain+0x16/0x20 4[ 363.117151] [81442a0a] cpufreq_notify_transition+0x12a/0x190 4[ 363.117151] [a026df08] powernowk8_target+0x628/0xb30 [powernow_k8] 4[ 363.117151] [8144289b] __cpufreq_driver_target+0x8b/0x90 4[ 363.117151] [a0279388] do_dbs_timer+0x3b8/0x3bc [cpufreq_ondemand] 4[ 363.117151] [a0278fd0] ? do_dbs_timer+0x0/0x3bc [cpufreq_ondemand] 4[ 363.117151] [81097df4] worker_thread+0x264/0x440 4[ 363.117151] [81097da3] ? worker_thread+0x213/0x440 4[ 363.117151] [81097b90] ? worker_thread+0x0/0x440 4[ 363.117151] [8109f050] ? autoremove_wake_function+0x0/0x40 4[ 363.117151] [81097b90] ? worker_thread+0x0/0x440 4[ 363.117151] [8109e986] kthread+0x96/0xa0 4[ 363.117151] [8100c34a] child_rip+0xa/0x20 4[ 363.117151] [8100bc90] ? restore_args+0x0/0x30 4[ 363.117151] [8109e8f0] ? kthread+0x0/0xa0 4[ 363.117151] [8100c340] ? child_rip+0x0/0x20 4[ 363.117151] Code: 89 f9 48 8b 0c cd 20 53 9c 81 4c 8b 24 08 4d 85 e4 74 d3 8b 4a 08 41 8b 54 24 10 45 8b 6c 24 18 85 d2 74 22 49 8b 74 24 28 31 db3b 0e 75 10 eb 1a 66 0f 1f 44 00 00 48 63 c3 3b 0c 86 74 0c 83 1[ 363.117151] RIP [a11a70e4] cpufreq_stat_notifier_trans+0x64/0xf0 [cpufreq_stats] 4[ 363.117151] RSP880234281920 4[ 363.117151] CR2: --- drivers/cpufreq/cpufreq_stats.c | 11 +++ 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/drivers/cpufreq/cpufreq_stats.c b/drivers/cpufreq/cpufreq_stats.c index e40e508..9d7732b 100644 --- a/drivers/cpufreq/cpufreq_stats.c +++ b/drivers/cpufreq/cpufreq_stats.c @@ -364,18 +364,21 @@ static int __init cpufreq_stats_init(void) if (ret) return ret; + register_hotcpu_notifier(cpufreq_stat_cpu_notifier); +
