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

From: Viresh Kumar
Date: Fri Mar 28 2014 - 06:14:46 EST


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.

Along with that we also remove use of .driver_data from SPEAr driver as it
doesn't use it at all. Also, writing zero to .driver_data is not required for
powernow-k8 as it is already zero.

Reported-by: Gautham R. Shenoy <ego@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
---
@Rafael: Please apply this one before:

http://permalink.gmane.org/gmane.linux.kernel/1673994

so that git bisect doesn't break. Though the chances of this field getting
initialized to a value equal to BOOST, i.e. 0x1 are very rare.

drivers/cpufreq/acpi-cpufreq.c | 2 +-
drivers/cpufreq/ia64-acpi-cpufreq.c | 2 +-
drivers/cpufreq/longhaul.c | 2 +-
drivers/cpufreq/powernow-k8.c | 5 ++---
drivers/cpufreq/s3c24xx-cpufreq.c | 4 ++--
drivers/cpufreq/spear-cpufreq.c | 7 ++-----
6 files changed, 9 insertions(+), 13 deletions(-)

diff --git a/drivers/cpufreq/acpi-cpufreq.c b/drivers/cpufreq/acpi-cpufreq.c
index d5eaedb..000e4e0 100644
--- 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)
goto err_unreg;
}

- data->freq_table = kmalloc(sizeof(*data->freq_table) *
+ data->freq_table = kzalloc(sizeof(*data->freq_table) *
(perf->state_count+1), GFP_KERNEL);
if (!data->freq_table) {
result = -ENOMEM;
diff --git a/drivers/cpufreq/ia64-acpi-cpufreq.c b/drivers/cpufreq/ia64-acpi-cpufreq.c
index beb191b..c30aaa6 100644
--- a/drivers/cpufreq/ia64-acpi-cpufreq.c
+++ b/drivers/cpufreq/ia64-acpi-cpufreq.c
@@ -254,7 +254,7 @@ acpi_cpufreq_cpu_init (
}

/* alloc freq_table */
- data->freq_table = kmalloc(sizeof(*data->freq_table) *
+ data->freq_table = kzalloc(sizeof(*data->freq_table) *
(data->acpi_data.state_count + 1),
GFP_KERNEL);
if (!data->freq_table) {
diff --git a/drivers/cpufreq/longhaul.c b/drivers/cpufreq/longhaul.c
index 5c440f8..d00e5d1 100644
--- a/drivers/cpufreq/longhaul.c
+++ b/drivers/cpufreq/longhaul.c
@@ -475,7 +475,7 @@ static int longhaul_get_ranges(void)
return -EINVAL;
}

- longhaul_table = kmalloc((numscales + 1) * sizeof(*longhaul_table),
+ longhaul_table = kzalloc((numscales + 1) * sizeof(*longhaul_table),
GFP_KERNEL);
if (!longhaul_table)
return -ENOMEM;
diff --git a/drivers/cpufreq/powernow-k8.c b/drivers/cpufreq/powernow-k8.c
index 770a9e1..1b6ae6b 100644
--- 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,
if (check_pst_table(data, pst, maxvid))
return -EINVAL;

- powernow_table = kmalloc((sizeof(*powernow_table)
+ powernow_table = kzalloc((sizeof(*powernow_table)
* (data->numps + 1)), GFP_KERNEL);
if (!powernow_table) {
printk(KERN_ERR PFX "powernow_table memory alloc failure\n");
@@ -793,7 +793,7 @@ static int powernow_k8_cpu_init_acpi(struct powernow_k8_data *data)
}

/* fill in data->powernow_table */
- powernow_table = kmalloc((sizeof(*powernow_table)
+ powernow_table = kzalloc((sizeof(*powernow_table)
* (data->acpi_data.state_count + 1)), GFP_KERNEL);
if (!powernow_table) {
pr_debug("powernow_table memory alloc failure\n");
@@ -810,7 +810,6 @@ static int powernow_k8_cpu_init_acpi(struct powernow_k8_data *data)

powernow_table[data->acpi_data.state_count].frequency =
CPUFREQ_TABLE_END;
- powernow_table[data->acpi_data.state_count].driver_data = 0;
data->powernow_table = powernow_table;

if (cpumask_first(cpu_core_mask(data->cpu)) == data->cpu)
diff --git a/drivers/cpufreq/s3c24xx-cpufreq.c b/drivers/cpufreq/s3c24xx-cpufreq.c
index a3dc192..be1b2b5 100644
--- a/drivers/cpufreq/s3c24xx-cpufreq.c
+++ b/drivers/cpufreq/s3c24xx-cpufreq.c
@@ -586,7 +586,7 @@ static int s3c_cpufreq_build_freq(void)
size = cpu_cur.info->calc_freqtable(&cpu_cur, NULL, 0);
size++;

- ftab = kmalloc(sizeof(*ftab) * size, GFP_KERNEL);
+ ftab = kzalloc(sizeof(*ftab) * size, GFP_KERNEL);
if (!ftab) {
printk(KERN_ERR "%s: no memory for tables\n", __func__);
return -ENOMEM;
@@ -664,7 +664,7 @@ int __init s3c_plltab_register(struct cpufreq_frequency_table *plls,

size = sizeof(*vals) * (plls_no + 1);

- vals = kmalloc(size, GFP_KERNEL);
+ vals = kzalloc(size, GFP_KERNEL);
if (vals) {
memcpy(vals, plls, size);
pll_reg = vals;
diff --git a/drivers/cpufreq/spear-cpufreq.c b/drivers/cpufreq/spear-cpufreq.c
index 4cfdcff..3867839 100644
--- 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)
cnt = prop->length / sizeof(u32);
val = prop->value;

- 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;

spear_cpufreq.freq_tbl = freq_tbl;
--
1.7.12.rc2.18.g61b472e

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