* [PATCH 1/5] PM / devfreq: Fix cpufreq passive unregister erroring on PROBE_DEFER
2022-06-06 11:10 [PATCH 0/5] PM / devfreq: Various Fixes to cpufreq based passive governor Christian 'Ansuel' Marangi
@ 2022-06-06 11:11 ` Christian 'Ansuel' Marangi
0 siblings, 0 replies; 5+ messages in thread
From: Christian 'Ansuel' Marangi @ 2022-06-06 11:11 UTC (permalink / raw)
To: MyungJoo Ham, Kyungmin Park, Chanwoo Choi, Saravana Kannan,
Sibi Sankar, linux-pm, linux-kernel
Cc: Christian 'Ansuel' Marangi
With the passive governor, the cpu based scaling can PROBE_DEFER due to
the fact that CPU policy are not ready.
The cpufreq passive unregister notifier is called both from the
GOV_START errors and for the GOV_STOP and assume the notifier is
successfully registred every time. With GOV_START failing it's wrong to
loop over each possible CPU since the register path has failed for
some CPU policy not ready. Change the logic and unregister the notifer
based on the current allocated parent_cpu_data list to correctly handle
errors and the governor unregister path.
Fixes: a03dacb0316f ("PM / devfreq: Add cpu based scaling support to passive governor")
Signed-off-by: Christian 'Ansuel' Marangi <ansuelsmth@gmail.com>
---
drivers/devfreq/governor_passive.c | 21 +++++----------------
1 file changed, 5 insertions(+), 16 deletions(-)
diff --git a/drivers/devfreq/governor_passive.c b/drivers/devfreq/governor_passive.c
index 72c67979ebe1..09b6c852fccc 100644
--- a/drivers/devfreq/governor_passive.c
+++ b/drivers/devfreq/governor_passive.c
@@ -223,7 +223,7 @@ static int cpufreq_passive_unregister_notifier(struct devfreq *devfreq)
struct devfreq_passive_data *p_data
= (struct devfreq_passive_data *)devfreq->data;
struct devfreq_cpu_data *parent_cpu_data;
- int cpu, ret = 0;
+ int ret;
if (p_data->nb.notifier_call) {
ret = cpufreq_unregister_notifier(&p_data->nb,
@@ -232,27 +232,16 @@ static int cpufreq_passive_unregister_notifier(struct devfreq *devfreq)
return ret;
}
- for_each_possible_cpu(cpu) {
- struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
- if (!policy) {
- ret = -EINVAL;
- continue;
- }
-
- parent_cpu_data = get_parent_cpu_data(p_data, policy);
- if (!parent_cpu_data) {
- cpufreq_cpu_put(policy);
- continue;
- }
-
+ list_for_each_entry(parent_cpu_data, &p_data->cpu_data_list, node) {
list_del(&parent_cpu_data->node);
+
if (parent_cpu_data->opp_table)
dev_pm_opp_put_opp_table(parent_cpu_data->opp_table);
+
kfree(parent_cpu_data);
- cpufreq_cpu_put(policy);
}
- return ret;
+ return 0;
}
static int cpufreq_passive_register_notifier(struct devfreq *devfreq)
--
2.36.1
^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [PATCH 1/5] PM / devfreq: Fix cpufreq passive unregister erroring on PROBE_DEFER
@ 2022-06-07 2:48 kernel test robot
0 siblings, 0 replies; 5+ messages in thread
From: kernel test robot @ 2022-06-07 2:48 UTC (permalink / raw)
To: kbuild
[-- Attachment #1: Type: text/plain, Size: 4458 bytes --]
::::::
:::::: Manual check reason: "low confidence static check warning: drivers/devfreq/governor_passive.c:238:24: warning: Uninitialized variable: parent_cpu_data->opp_table [uninitvar]"
::::::
CC: kbuild-all(a)lists.01.org
BCC: lkp(a)intel.com
In-Reply-To: <20220606111104.14534-2-ansuelsmth@gmail.com>
References: <20220606111104.14534-2-ansuelsmth@gmail.com>
TO: "Christian 'Ansuel' Marangi" <ansuelsmth@gmail.com>
TO: MyungJoo Ham <myungjoo.ham@samsung.com>
TO: Kyungmin Park <kyungmin.park@samsung.com>
TO: Chanwoo Choi <cw00.choi@samsung.com>
TO: Saravana Kannan <skannan@codeaurora.org>
TO: Sibi Sankar <sibis@codeaurora.org>
TO: linux-pm(a)vger.kernel.org
TO: linux-kernel(a)vger.kernel.org
CC: "Christian 'Ansuel' Marangi" <ansuelsmth@gmail.com>
Hi Christian,
Thank you for the patch! Perhaps something to improve:
[auto build test WARNING on chanwoo/devfreq-testing]
[also build test WARNING on linus/master v5.19-rc1 next-20220606]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/intel-lab-lkp/linux/commits/Christian-Ansuel-Marangi/PM-devfreq-Various-Fixes-to-cpufreq-based-passive-governor/20220606-191335
base: https://git.kernel.org/pub/scm/linux/kernel/git/chanwoo/linux.git devfreq-testing
:::::: branch date: 16 hours ago
:::::: commit date: 16 hours ago
compiler: riscv64-linux-gcc (GCC) 11.3.0
reproduce (cppcheck warning):
# apt-get install cppcheck
git checkout 2d59e1f0c418bf7a6fb2396c60a643994b4c4aba
cppcheck --quiet --enable=style,performance,portability --template=gcc FILE
If you fix the issue, kindly add following tag where applicable
Reported-by: kernel test robot <lkp@intel.com>
cppcheck possible warnings: (new ones prefixed by >>, may not real problems)
>> drivers/devfreq/governor_passive.c:238:24: warning: Uninitialized variable: parent_cpu_data->opp_table [uninitvar]
if (parent_cpu_data->opp_table)
^
vim +238 drivers/devfreq/governor_passive.c
a03dacb0316f74 Saravana Kannan 2021-03-02 220
a03dacb0316f74 Saravana Kannan 2021-03-02 221 static int cpufreq_passive_unregister_notifier(struct devfreq *devfreq)
a03dacb0316f74 Saravana Kannan 2021-03-02 222 {
a03dacb0316f74 Saravana Kannan 2021-03-02 223 struct devfreq_passive_data *p_data
a03dacb0316f74 Saravana Kannan 2021-03-02 224 = (struct devfreq_passive_data *)devfreq->data;
a03dacb0316f74 Saravana Kannan 2021-03-02 225 struct devfreq_cpu_data *parent_cpu_data;
2d59e1f0c418bf Christian 'Ansuel' Marangi 2022-06-06 226 int ret;
a03dacb0316f74 Saravana Kannan 2021-03-02 227
a03dacb0316f74 Saravana Kannan 2021-03-02 228 if (p_data->nb.notifier_call) {
a03dacb0316f74 Saravana Kannan 2021-03-02 229 ret = cpufreq_unregister_notifier(&p_data->nb,
a03dacb0316f74 Saravana Kannan 2021-03-02 230 CPUFREQ_TRANSITION_NOTIFIER);
a03dacb0316f74 Saravana Kannan 2021-03-02 231 if (ret < 0)
a03dacb0316f74 Saravana Kannan 2021-03-02 232 return ret;
a03dacb0316f74 Saravana Kannan 2021-03-02 233 }
a03dacb0316f74 Saravana Kannan 2021-03-02 234
2d59e1f0c418bf Christian 'Ansuel' Marangi 2022-06-06 235 list_for_each_entry(parent_cpu_data, &p_data->cpu_data_list, node) {
26984d9d581e50 Chanwoo Choi 2022-04-27 236 list_del(&parent_cpu_data->node);
2d59e1f0c418bf Christian 'Ansuel' Marangi 2022-06-06 237
a03dacb0316f74 Saravana Kannan 2021-03-02 @238 if (parent_cpu_data->opp_table)
a03dacb0316f74 Saravana Kannan 2021-03-02 239 dev_pm_opp_put_opp_table(parent_cpu_data->opp_table);
2d59e1f0c418bf Christian 'Ansuel' Marangi 2022-06-06 240
a03dacb0316f74 Saravana Kannan 2021-03-02 241 kfree(parent_cpu_data);
a03dacb0316f74 Saravana Kannan 2021-03-02 242 }
a03dacb0316f74 Saravana Kannan 2021-03-02 243
2d59e1f0c418bf Christian 'Ansuel' Marangi 2022-06-06 244 return 0;
a03dacb0316f74 Saravana Kannan 2021-03-02 245 }
a03dacb0316f74 Saravana Kannan 2021-03-02 246
--
0-DAY CI Kernel Test Service
https://01.org/lkp
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH 1/5] PM / devfreq: Fix cpufreq passive unregister erroring on PROBE_DEFER
2022-06-06 11:11 ` [PATCH 1/5] PM / devfreq: Fix cpufreq passive unregister erroring on PROBE_DEFER Christian 'Ansuel' Marangi
(?)
@ 2022-06-10 6:41 ` Dan Carpenter
-1 siblings, 0 replies; 5+ messages in thread
From: kernel test robot @ 2022-06-10 3:25 UTC (permalink / raw)
To: kbuild
[-- Attachment #1: Type: text/plain, Size: 4116 bytes --]
CC: kbuild-all(a)lists.01.org
BCC: lkp(a)intel.com
In-Reply-To: <20220606111104.14534-2-ansuelsmth@gmail.com>
References: <20220606111104.14534-2-ansuelsmth@gmail.com>
TO: "Christian 'Ansuel' Marangi" <ansuelsmth@gmail.com>
TO: MyungJoo Ham <myungjoo.ham@samsung.com>
TO: Kyungmin Park <kyungmin.park@samsung.com>
TO: Chanwoo Choi <cw00.choi@samsung.com>
TO: Saravana Kannan <skannan@codeaurora.org>
TO: Sibi Sankar <sibis@codeaurora.org>
TO: linux-pm(a)vger.kernel.org
TO: linux-kernel(a)vger.kernel.org
CC: "Christian 'Ansuel' Marangi" <ansuelsmth@gmail.com>
Hi Christian,
Thank you for the patch! Perhaps something to improve:
[auto build test WARNING on chanwoo/devfreq-testing]
[also build test WARNING on linus/master v5.19-rc1 next-20220609]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/intel-lab-lkp/linux/commits/Christian-Ansuel-Marangi/PM-devfreq-Various-Fixes-to-cpufreq-based-passive-governor/20220606-191335
base: https://git.kernel.org/pub/scm/linux/kernel/git/chanwoo/linux.git devfreq-testing
:::::: branch date: 4 days ago
:::::: commit date: 4 days ago
config: i386-randconfig-m021 (https://download.01.org/0day-ci/archive/20220610/202206101102.4JCYtCjM-lkp(a)intel.com/config)
compiler: gcc-11 (Debian 11.3.0-1) 11.3.0
If you fix the issue, kindly add following tag where applicable
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
smatch warnings:
drivers/devfreq/governor_passive.c:235 cpufreq_passive_unregister_notifier() error: dereferencing freed memory 'parent_cpu_data'
vim +/parent_cpu_data +235 drivers/devfreq/governor_passive.c
a03dacb0316f74 Saravana Kannan 2021-03-02 220
a03dacb0316f74 Saravana Kannan 2021-03-02 221 static int cpufreq_passive_unregister_notifier(struct devfreq *devfreq)
a03dacb0316f74 Saravana Kannan 2021-03-02 222 {
a03dacb0316f74 Saravana Kannan 2021-03-02 223 struct devfreq_passive_data *p_data
a03dacb0316f74 Saravana Kannan 2021-03-02 224 = (struct devfreq_passive_data *)devfreq->data;
a03dacb0316f74 Saravana Kannan 2021-03-02 225 struct devfreq_cpu_data *parent_cpu_data;
2d59e1f0c418bf Christian 'Ansuel' Marangi 2022-06-06 226 int ret;
a03dacb0316f74 Saravana Kannan 2021-03-02 227
a03dacb0316f74 Saravana Kannan 2021-03-02 228 if (p_data->nb.notifier_call) {
a03dacb0316f74 Saravana Kannan 2021-03-02 229 ret = cpufreq_unregister_notifier(&p_data->nb,
a03dacb0316f74 Saravana Kannan 2021-03-02 230 CPUFREQ_TRANSITION_NOTIFIER);
a03dacb0316f74 Saravana Kannan 2021-03-02 231 if (ret < 0)
a03dacb0316f74 Saravana Kannan 2021-03-02 232 return ret;
a03dacb0316f74 Saravana Kannan 2021-03-02 233 }
a03dacb0316f74 Saravana Kannan 2021-03-02 234
2d59e1f0c418bf Christian 'Ansuel' Marangi 2022-06-06 @235 list_for_each_entry(parent_cpu_data, &p_data->cpu_data_list, node) {
26984d9d581e50 Chanwoo Choi 2022-04-27 236 list_del(&parent_cpu_data->node);
2d59e1f0c418bf Christian 'Ansuel' Marangi 2022-06-06 237
a03dacb0316f74 Saravana Kannan 2021-03-02 238 if (parent_cpu_data->opp_table)
a03dacb0316f74 Saravana Kannan 2021-03-02 239 dev_pm_opp_put_opp_table(parent_cpu_data->opp_table);
2d59e1f0c418bf Christian 'Ansuel' Marangi 2022-06-06 240
a03dacb0316f74 Saravana Kannan 2021-03-02 241 kfree(parent_cpu_data);
a03dacb0316f74 Saravana Kannan 2021-03-02 242 }
a03dacb0316f74 Saravana Kannan 2021-03-02 243
2d59e1f0c418bf Christian 'Ansuel' Marangi 2022-06-06 244 return 0;
a03dacb0316f74 Saravana Kannan 2021-03-02 245 }
a03dacb0316f74 Saravana Kannan 2021-03-02 246
--
0-DAY CI Kernel Test Service
https://01.org/lkp
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH 1/5] PM / devfreq: Fix cpufreq passive unregister erroring on PROBE_DEFER
@ 2022-06-10 6:41 ` Dan Carpenter
0 siblings, 0 replies; 5+ messages in thread
From: Dan Carpenter @ 2022-06-10 6:41 UTC (permalink / raw)
To: kbuild, Christian 'Ansuel' Marangi, MyungJoo Ham,
Kyungmin Park, Chanwoo Choi, Saravana Kannan, Sibi Sankar,
linux-pm, linux-kernel
Cc: lkp, kbuild-all, Christian 'Ansuel' Marangi
Hi Christian,
url: https://github.com/intel-lab-lkp/linux/commits/Christian-Ansuel-Marangi/PM-devfreq-Various-Fixes-to-cpufreq-based-passive-governor/20220606-191335
base: https://git.kernel.org/pub/scm/linux/kernel/git/chanwoo/linux.git devfreq-testing
config: i386-randconfig-m021 (https://download.01.org/0day-ci/archive/20220610/202206101102.4JCYtCjM-lkp@intel.com/config)
compiler: gcc-11 (Debian 11.3.0-1) 11.3.0
If you fix the issue, kindly add following tag where applicable
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
smatch warnings:
drivers/devfreq/governor_passive.c:235 cpufreq_passive_unregister_notifier() error: dereferencing freed memory 'parent_cpu_data'
vim +/parent_cpu_data +235 drivers/devfreq/governor_passive.c
a03dacb0316f74 Saravana Kannan 2021-03-02 221 static int cpufreq_passive_unregister_notifier(struct devfreq *devfreq)
a03dacb0316f74 Saravana Kannan 2021-03-02 222 {
a03dacb0316f74 Saravana Kannan 2021-03-02 223 struct devfreq_passive_data *p_data
a03dacb0316f74 Saravana Kannan 2021-03-02 224 = (struct devfreq_passive_data *)devfreq->data;
a03dacb0316f74 Saravana Kannan 2021-03-02 225 struct devfreq_cpu_data *parent_cpu_data;
2d59e1f0c418bf Christian 'Ansuel' Marangi 2022-06-06 226 int ret;
a03dacb0316f74 Saravana Kannan 2021-03-02 227
a03dacb0316f74 Saravana Kannan 2021-03-02 228 if (p_data->nb.notifier_call) {
a03dacb0316f74 Saravana Kannan 2021-03-02 229 ret = cpufreq_unregister_notifier(&p_data->nb,
a03dacb0316f74 Saravana Kannan 2021-03-02 230 CPUFREQ_TRANSITION_NOTIFIER);
a03dacb0316f74 Saravana Kannan 2021-03-02 231 if (ret < 0)
a03dacb0316f74 Saravana Kannan 2021-03-02 232 return ret;
a03dacb0316f74 Saravana Kannan 2021-03-02 233 }
a03dacb0316f74 Saravana Kannan 2021-03-02 234
2d59e1f0c418bf Christian 'Ansuel' Marangi 2022-06-06 @235 list_for_each_entry(parent_cpu_data, &p_data->cpu_data_list, node) {
This needs to be list_for_each_entry_safe()
26984d9d581e50 Chanwoo Choi 2022-04-27 236 list_del(&parent_cpu_data->node);
Otherwise it will only iterate one time
2d59e1f0c418bf Christian 'Ansuel' Marangi 2022-06-06 237
a03dacb0316f74 Saravana Kannan 2021-03-02 238 if (parent_cpu_data->opp_table)
a03dacb0316f74 Saravana Kannan 2021-03-02 239 dev_pm_opp_put_opp_table(parent_cpu_data->opp_table);
2d59e1f0c418bf Christian 'Ansuel' Marangi 2022-06-06 240
a03dacb0316f74 Saravana Kannan 2021-03-02 241 kfree(parent_cpu_data);
And it will dereference a freed pointer
a03dacb0316f74 Saravana Kannan 2021-03-02 242 }
a03dacb0316f74 Saravana Kannan 2021-03-02 243
2d59e1f0c418bf Christian 'Ansuel' Marangi 2022-06-06 244 return 0;
a03dacb0316f74 Saravana Kannan 2021-03-02 245 }
--
0-DAY CI Kernel Test Service
https://01.org/lkp
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH 1/5] PM / devfreq: Fix cpufreq passive unregister erroring on PROBE_DEFER
@ 2022-06-10 6:41 ` Dan Carpenter
0 siblings, 0 replies; 5+ messages in thread
From: Dan Carpenter @ 2022-06-10 6:41 UTC (permalink / raw)
To: kbuild-all
[-- Attachment #1: Type: text/plain, Size: 3125 bytes --]
Hi Christian,
url: https://github.com/intel-lab-lkp/linux/commits/Christian-Ansuel-Marangi/PM-devfreq-Various-Fixes-to-cpufreq-based-passive-governor/20220606-191335
base: https://git.kernel.org/pub/scm/linux/kernel/git/chanwoo/linux.git devfreq-testing
config: i386-randconfig-m021 (https://download.01.org/0day-ci/archive/20220610/202206101102.4JCYtCjM-lkp(a)intel.com/config)
compiler: gcc-11 (Debian 11.3.0-1) 11.3.0
If you fix the issue, kindly add following tag where applicable
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
smatch warnings:
drivers/devfreq/governor_passive.c:235 cpufreq_passive_unregister_notifier() error: dereferencing freed memory 'parent_cpu_data'
vim +/parent_cpu_data +235 drivers/devfreq/governor_passive.c
a03dacb0316f74 Saravana Kannan 2021-03-02 221 static int cpufreq_passive_unregister_notifier(struct devfreq *devfreq)
a03dacb0316f74 Saravana Kannan 2021-03-02 222 {
a03dacb0316f74 Saravana Kannan 2021-03-02 223 struct devfreq_passive_data *p_data
a03dacb0316f74 Saravana Kannan 2021-03-02 224 = (struct devfreq_passive_data *)devfreq->data;
a03dacb0316f74 Saravana Kannan 2021-03-02 225 struct devfreq_cpu_data *parent_cpu_data;
2d59e1f0c418bf Christian 'Ansuel' Marangi 2022-06-06 226 int ret;
a03dacb0316f74 Saravana Kannan 2021-03-02 227
a03dacb0316f74 Saravana Kannan 2021-03-02 228 if (p_data->nb.notifier_call) {
a03dacb0316f74 Saravana Kannan 2021-03-02 229 ret = cpufreq_unregister_notifier(&p_data->nb,
a03dacb0316f74 Saravana Kannan 2021-03-02 230 CPUFREQ_TRANSITION_NOTIFIER);
a03dacb0316f74 Saravana Kannan 2021-03-02 231 if (ret < 0)
a03dacb0316f74 Saravana Kannan 2021-03-02 232 return ret;
a03dacb0316f74 Saravana Kannan 2021-03-02 233 }
a03dacb0316f74 Saravana Kannan 2021-03-02 234
2d59e1f0c418bf Christian 'Ansuel' Marangi 2022-06-06 @235 list_for_each_entry(parent_cpu_data, &p_data->cpu_data_list, node) {
This needs to be list_for_each_entry_safe()
26984d9d581e50 Chanwoo Choi 2022-04-27 236 list_del(&parent_cpu_data->node);
Otherwise it will only iterate one time
2d59e1f0c418bf Christian 'Ansuel' Marangi 2022-06-06 237
a03dacb0316f74 Saravana Kannan 2021-03-02 238 if (parent_cpu_data->opp_table)
a03dacb0316f74 Saravana Kannan 2021-03-02 239 dev_pm_opp_put_opp_table(parent_cpu_data->opp_table);
2d59e1f0c418bf Christian 'Ansuel' Marangi 2022-06-06 240
a03dacb0316f74 Saravana Kannan 2021-03-02 241 kfree(parent_cpu_data);
And it will dereference a freed pointer
a03dacb0316f74 Saravana Kannan 2021-03-02 242 }
a03dacb0316f74 Saravana Kannan 2021-03-02 243
2d59e1f0c418bf Christian 'Ansuel' Marangi 2022-06-06 244 return 0;
a03dacb0316f74 Saravana Kannan 2021-03-02 245 }
--
0-DAY CI Kernel Test Service
https://01.org/lkp
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2022-06-10 6:43 UTC | newest]
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2022-06-07 2:48 [PATCH 1/5] PM / devfreq: Fix cpufreq passive unregister erroring on PROBE_DEFER kernel test robot
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2022-06-10 3:25 kernel test robot
2022-06-10 6:41 ` Dan Carpenter
2022-06-10 6:41 ` Dan Carpenter
2022-06-06 11:10 [PATCH 0/5] PM / devfreq: Various Fixes to cpufreq based passive governor Christian 'Ansuel' Marangi
2022-06-06 11:11 ` [PATCH 1/5] PM / devfreq: Fix cpufreq passive unregister erroring on PROBE_DEFER Christian 'Ansuel' Marangi
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