cpufreq: powernow-k8: Initialize per-cpu data-structures properly
The powernow-k8 driver maintains a per-cpu data-structure called powernow_data that is used to perform the frequency transitions. It initializes this data structure only for the policy->cpu. So, accesses to this data structure by other CPUs results in various problems because they would have been uninitialized. Specifically, if a cpu (!= policy->cpu) invokes the drivers' ->get() function, it returns 0 as the KHz value, since its per-cpu memory doesn't point to anything valid. This causes problems during suspend/resume since cpufreq_update_policy() tries to enforce this (0 KHz) as the current frequency of the CPU, and this madness gets propagated to adjust_jiffies() as well. Eventually, lots of things start breaking down, including the r8169 ethernet card, in one particularly interesting case reported by Pierre Ossman. Fix this by initializing the per-cpu data-structures of all the CPUs in the policy appropriately. References: https://bugzilla.kernel.org/show_bug.cgi?id=70311 Reported-by: Pierre Ossman <pierre@ossman.eu> Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Cc: All applicable <stable@vger.kernel.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
parent
6964d91db2
commit
c3274763bf
|
@ -1076,7 +1076,7 @@ static int powernowk8_cpu_init(struct cpufreq_policy *pol)
|
|||
{
|
||||
struct powernow_k8_data *data;
|
||||
struct init_on_cpu init_on_cpu;
|
||||
int rc;
|
||||
int rc, cpu;
|
||||
|
||||
smp_call_function_single(pol->cpu, check_supported_cpu, &rc, 1);
|
||||
if (rc)
|
||||
|
@ -1140,7 +1140,9 @@ static int powernowk8_cpu_init(struct cpufreq_policy *pol)
|
|||
pr_debug("cpu_init done, current fid 0x%x, vid 0x%x\n",
|
||||
data->currfid, data->currvid);
|
||||
|
||||
per_cpu(powernow_data, pol->cpu) = data;
|
||||
/* Point all the CPUs in this policy to the same data */
|
||||
for_each_cpu(cpu, pol->cpus)
|
||||
per_cpu(powernow_data, cpu) = data;
|
||||
|
||||
return 0;
|
||||
|
||||
|
@ -1155,6 +1157,7 @@ err_out:
|
|||
static int powernowk8_cpu_exit(struct cpufreq_policy *pol)
|
||||
{
|
||||
struct powernow_k8_data *data = per_cpu(powernow_data, pol->cpu);
|
||||
int cpu;
|
||||
|
||||
if (!data)
|
||||
return -EINVAL;
|
||||
|
@ -1165,7 +1168,8 @@ static int powernowk8_cpu_exit(struct cpufreq_policy *pol)
|
|||
|
||||
kfree(data->powernow_table);
|
||||
kfree(data);
|
||||
per_cpu(powernow_data, pol->cpu) = NULL;
|
||||
for_each_cpu(cpu, pol->cpus)
|
||||
per_cpu(powernow_data, cpu) = NULL;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
|
Loading…
Reference in a new issue