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| author | Colin Ian King <colin.king@canonical.com> | 2021-01-05 13:19:57 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-01-17 15:58:59 +0300 |
| commit | b4f18c95ae5d893385c117467130a88e8d87337a (patch) | |
| tree | 1de238dafab4d89ef52660f2c3ed8c967ed1cdd3 /drivers | |
| parent | 3d87acd7e4ac0df83d8c8bb445923c415bf7171a (diff) | |
| download | linux-b4f18c95ae5d893385c117467130a88e8d87337a.tar.xz | |
cpufreq: powernow-k8: pass policy rather than use cpufreq_cpu_get()
commit 943bdd0cecad06da8392a33093230e30e501eccc upstream.
Currently there is an unlikely case where cpufreq_cpu_get() returns a
NULL policy and this will cause a NULL pointer dereference later on.
Fix this by passing the policy to transition_frequency_fidvid() from
the caller and hence eliminating the need for the cpufreq_cpu_get()
and cpufreq_cpu_put().
Thanks to Viresh Kumar for suggesting the fix.
Addresses-Coverity: ("Dereference null return")
Fixes: b43a7ffbf33b ("cpufreq: Notify all policy->cpus in cpufreq_notify_transition()")
Suggested-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/cpufreq/powernow-k8.c | 9 |
1 files changed, 3 insertions, 6 deletions
diff --git a/drivers/cpufreq/powernow-k8.c b/drivers/cpufreq/powernow-k8.c index 062d71434e47..32bb00a6fe09 100644 --- a/drivers/cpufreq/powernow-k8.c +++ b/drivers/cpufreq/powernow-k8.c @@ -887,9 +887,9 @@ static int get_transition_latency(struct powernow_k8_data *data) /* Take a frequency, and issue the fid/vid transition command */ static int transition_frequency_fidvid(struct powernow_k8_data *data, - unsigned int index) + unsigned int index, + struct cpufreq_policy *policy) { - struct cpufreq_policy *policy; u32 fid = 0; u32 vid = 0; int res; @@ -921,9 +921,6 @@ static int transition_frequency_fidvid(struct powernow_k8_data *data, freqs.old = find_khz_freq_from_fid(data->currfid); freqs.new = find_khz_freq_from_fid(fid); - policy = cpufreq_cpu_get(smp_processor_id()); - cpufreq_cpu_put(policy); - cpufreq_freq_transition_begin(policy, &freqs); res = transition_fid_vid(data, fid, vid); cpufreq_freq_transition_end(policy, &freqs, res); @@ -978,7 +975,7 @@ static long powernowk8_target_fn(void *arg) powernow_k8_acpi_pst_values(data, newstate); - ret = transition_frequency_fidvid(data, newstate); + ret = transition_frequency_fidvid(data, newstate, pol); if (ret) { pr_err("transition frequency failed\n"); |