| Message ID | 1554082674-2049-8-git-send-email-wen.yang99@zte.com.cn (mailing list archive) |
|---|---|
| State | Accepted |
| Delegated to: | viresh kumar |
| Headers | show |
| Series | [1/7] cpufreq: ap806: fix possible object reference leak | expand |
> The call to of_get_cpu_node returns a node pointer with refcount > incremented thus it must be explicitly decremented after the last > usage. I would prefer a wording like the following. A reference counter was incremented for a CPU node by a call of the function “of_get_cpu_node”. Thus decrement it after the last usage. > Detected by coccinelle with the following warnings: I wonder about the shown duplicate notification. Can a single message be sufficient for the code search result in this source file? Regards, Markus
On Tue, 2 Apr 2019, Markus Elfring wrote: > > The call to of_get_cpu_node returns a node pointer with refcount > > incremented thus it must be explicitly decremented after the last > > usage. > > I would prefer a wording like the following. > > A reference counter was incremented for a CPU node by a call of > the function “of_get_cpu_node”. > Thus decrement it after the last usage. The original log message seems perfectly clear. > > > > Detected by coccinelle with the following warnings: > > I wonder about the shown duplicate notification. > Can a single message be sufficient for the code search result > in this source file? Since you have removed the context, I have no idea what you are talking about. julia
> @@ -86,6 +86,7 @@ static int cbe_cpufreq_cpu_init(struct cpufreq_policy *policy) > if (!cbe_get_cpu_pmd_regs(policy->cpu) || > !cbe_get_cpu_mic_tm_regs(policy->cpu)) { > pr_info("invalid CBE regs pointers for cpufreq\n"); > + of_node_put(cpu); > return -EINVAL; > } I have taken another look at the implementation of this function. I find that the second statement “return -EINVAL” would need related source code adjustments. https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/tree/drivers/cpufreq/ppc_cbe_cpufreq.c?id=05d08e2995cbe6efdb993482ee0d38a77040861a#n96 How do you think about to complete the exception handling here? Regards, Markus
On Tue, 2 Apr 2019, Markus Elfring wrote: > > @@ -86,6 +86,7 @@ static int cbe_cpufreq_cpu_init(struct cpufreq_policy *policy) > > if (!cbe_get_cpu_pmd_regs(policy->cpu) || > > !cbe_get_cpu_mic_tm_regs(policy->cpu)) { > > pr_info("invalid CBE regs pointers for cpufreq\n"); > > + of_node_put(cpu); > > return -EINVAL; > > } > > I have taken another look at the implementation of this function. > I find that the second statement “return -EINVAL” would need related > source code adjustments. > https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/tree/drivers/cpufreq/ppc_cbe_cpufreq.c?id=05d08e2995cbe6efdb993482ee0d38a77040861a#n96 > > How do you think about to complete the exception handling here? There is an of_node_put two lines above. julia
diff --git a/drivers/cpufreq/ppc_cbe_cpufreq.c b/drivers/cpufreq/ppc_cbe_cpufreq.c index 41a0f0b..8414c3a 100644 --- a/drivers/cpufreq/ppc_cbe_cpufreq.c +++ b/drivers/cpufreq/ppc_cbe_cpufreq.c @@ -86,6 +86,7 @@ static int cbe_cpufreq_cpu_init(struct cpufreq_policy *policy) if (!cbe_get_cpu_pmd_regs(policy->cpu) || !cbe_get_cpu_mic_tm_regs(policy->cpu)) { pr_info("invalid CBE regs pointers for cpufreq\n"); + of_node_put(cpu); return -EINVAL; }
The call to of_get_cpu_node returns a node pointer with refcount incremented thus it must be explicitly decremented after the last usage. Detected by coccinelle with the following warnings: ./drivers/cpufreq/ppc_cbe_cpufreq.c:89:2-8: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 76, but without a corresponding object release within this function. ./drivers/cpufreq/ppc_cbe_cpufreq.c:89:2-8: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 76, but without a corresponding object release within this function. Signed-off-by: Wen Yang <wen.yang99@zte.com.cn> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: linux-pm@vger.kernel.org Cc: linux-kernel@vger.kernel.org --- drivers/cpufreq/ppc_cbe_cpufreq.c | 1 + 1 file changed, 1 insertion(+)