Re: [PATCH] cpufreq: use kzalloc() to allocate memory for cpufreq_frequency_table

On Fri, 2014-03-28 at 15:44 +0530, Viresh Kumar wrote:

Few drivers are using kmalloc() to allocate memory for frequency tables and once we have an additional field '.flags' in 'struct cpufreq_frequency_table', these might become unstable. Better get these fixed by replacing kmalloc() by kzalloc() instead.

There seems to be some sort of bug fix in the patch at the very end too?

Perhaps a better fix would be to use kcalloc for all the allocs with a multiply.

diff --git a/drivers/cpufreq/acpi-cpufreq.c b/drivers/cpufreq/acpi-cpufreq.c

[]

@@ -754,7 +754,7 @@ static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)

[]

• data->freq_table = kmalloc(sizeof(*data->freq_table) *

• data->freq_table = kzalloc(sizeof(*data->freq_table) * (perf->state_count+1), GFP_KERNEL);

diff --git a/drivers/cpufreq/ia64-acpi-cpufreq.c b/drivers/cpufreq/ia64-acpi-cpufreq.c

[]

@@ -254,7 +254,7 @@ acpi_cpufreq_cpu_init (

[]

• data->freq_table = kmalloc(sizeof(*data->freq_table) *

• data->freq_table = kzalloc(sizeof(*data->freq_table) * (data->acpi_data.state_count + 1), GFP_KERNEL);

diff --git a/drivers/cpufreq/longhaul.c b/drivers/cpufreq/longhaul.c

[]

@@ -475,7 +475,7 @@ static int longhaul_get_ranges(void)

[]

• longhaul_table = kmalloc((numscales + 1) * sizeof(*longhaul_table),

diff --git a/drivers/cpufreq/powernow-k8.c b/drivers/cpufreq/powernow-k8.c

[]

@@ -623,7 +623,7 @@ static int fill_powernow_table(struct powernow_k8_data *data,

[]

• powernow_table = kmalloc((sizeof(*powernow_table)

• powernow_table = kzalloc((sizeof(*powernow_table)
  • (data->numps + 1)), GFP_KERNEL);

diff --git a/drivers/cpufreq/s3c24xx-cpufreq.c b/drivers/cpufreq/s3c24xx-cpufreq.c

[]

@@ -586,7 +586,7 @@ static int s3c_cpufreq_build_freq(void)

[]

• ftab = kmalloc(sizeof(*ftab) * size, GFP_KERNEL);

• ftab = kzalloc(sizeof(*ftab) * size, GFP_KERNEL);

diff --git a/drivers/cpufreq/spear-cpufreq.c b/drivers/cpufreq/spear-cpufreq.c

[]

@@ -195,18 +195,15 @@ static int spear_cpufreq_probe(struct platform_device *pdev)

[]

• freq_tbl = kmalloc(sizeof(*freq_tbl) * (cnt + 1), GFP_KERNEL);

• freq_tbl = kzalloc(sizeof(*freq_tbl) * (cnt + 1), GFP_KERNEL); if (!freq_tbl) { ret = -ENOMEM; goto out_put_node; }

• for (i = 0; i < cnt; i++) {

• freq_tbl[i].driver_data = i;
  

• for (i = 0; i < cnt; i++) freq_tbl[i].frequency = be32_to_cpup(val++);

• }

• freq_tbl[i].driver_data = i; freq_tbl[i].frequency = CPUFREQ_TABLE_END;

Is this some bug fix?