On 25 May 2016 at 15:09, Hoan Tran <hot...@apm.com> wrote: > When CPPC fails to request PCC channel, the CPC data is freed > and cpc_desc_ptr points to the invalid data. This change prevents > this issue by moving cpc_desc_ptr assignment after PCC channel > request. > > Signed-off-by: Hoan Tran <hot...@apm.com> > --- > drivers/acpi/cppc_acpi.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c > index 8adac69..85fd8f7 100644 > --- a/drivers/acpi/cppc_acpi.c > +++ b/drivers/acpi/cppc_acpi.c > @@ -595,9 +595,6 @@ int acpi_cppc_processor_probe(struct acpi_processor *pr) > /* Store CPU Logical ID */ > cpc_ptr->cpu_id = pr->id; > > - /* Plug it into this CPUs CPC descriptor. */ > - per_cpu(cpc_desc_ptr, pr->id) = cpc_ptr; > - > /* Parse PSD data for this CPU */ > ret = acpi_get_psd(cpc_ptr, handle); > if (ret) > @@ -610,6 +607,9 @@ int acpi_cppc_processor_probe(struct acpi_processor *pr) > goto out_free; > } > > + /* Plug PSD data into this CPUs CPC descriptor. */ > + per_cpu(cpc_desc_ptr, pr->id) = cpc_ptr; > +
Are you seeing a real problem without this change? I'm missing where this pointer is dereferenced if the PCC channel request fails. Thanks, Ashwin.
