Make the per_cpu(processors, cpu) entries available earlier so that
they are available in arch_register_cpu() as ARM64 will need access
to the acpi_handle to distinguish between acpi_processor_add()
and earlier registration attempts (which will fail as _STA cannot
be checked).
Reorder the remove flow to clear this per_cpu() after
arch_unregister_cpu() has completed, allowing it to be used in
there as well.
Note that on x86 for the CPU hotplug case, the pr->id prior to
acpi_map_cpu() may be invalid. Thus the per_cpu() structures
must be initialized after that call or after checking the ID
is valid (not hotplug path).
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
---
v9: Add back a blank line accidentally removed in code move.
Fix up error returns so that the new cleanup in processor_add()
is triggered on detection of the bios bug.
Combined with the previous 2 patches, should solve the leak
that Gavin identified.
---
drivers/acpi/acpi_processor.c | 80 +++++++++++++++++++++--------------
1 file changed, 49 insertions(+), 31 deletions(-)
diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c
index 16e36e55a560..4a79b42d649e 100644
--- a/drivers/acpi/acpi_processor.c
+++ b/drivers/acpi/acpi_processor.c
@@ -183,8 +183,38 @@ static void __init acpi_pcc_cpufreq_init(void) {}
#endif /* CONFIG_X86 */
/* Initialization */
+static DEFINE_PER_CPU(void *, processor_device_array);
+
+static bool acpi_processor_set_per_cpu(struct acpi_processor *pr,
+ struct acpi_device *device)
+{
+ BUG_ON(pr->id >= nr_cpu_ids);
+
+ /*
+ * Buggy BIOS check.
+ * ACPI id of processors can be reported wrongly by the BIOS.
+ * Don't trust it blindly
+ */
+ if (per_cpu(processor_device_array, pr->id) != NULL &&
+ per_cpu(processor_device_array, pr->id) != device) {
+ dev_warn(&device->dev,
+ "BIOS reported wrong ACPI id %d for the processor\n",
+ pr->id);
+ return false;
+ }
+ /*
+ * processor_device_array is not cleared on errors to allow buggy BIOS
+ * checks.
+ */
+ per_cpu(processor_device_array, pr->id) = device;
+ per_cpu(processors, pr->id) = pr;
+
+ return true;
+}
+
#ifdef CONFIG_ACPI_HOTPLUG_CPU
-static int acpi_processor_hotadd_init(struct acpi_processor *pr)
+static int acpi_processor_hotadd_init(struct acpi_processor *pr,
+ struct acpi_device *device)
{
int ret;
@@ -198,8 +228,16 @@ static int acpi_processor_hotadd_init(struct acpi_processor *pr)
if (ret)
goto out;
+ if (!acpi_processor_set_per_cpu(pr, device)) {
+ ret = -EINVAL;
+ acpi_unmap_cpu(pr->id);
+ goto out;
+ }
+
ret = arch_register_cpu(pr->id);
if (ret) {
+ /* Leave the processor device array in place to detect buggy bios */
+ per_cpu(processors, pr->id) = NULL;
acpi_unmap_cpu(pr->id);
goto out;
}
@@ -217,7 +255,8 @@ static int acpi_processor_hotadd_init(struct acpi_processor *pr)
return ret;
}
#else
-static inline int acpi_processor_hotadd_init(struct acpi_processor *pr)
+static inline int acpi_processor_hotadd_init(struct acpi_processor *pr,
+ struct acpi_device *device)
{
return -ENODEV;
}
@@ -316,10 +355,13 @@ static int acpi_processor_get_info(struct acpi_device *device)
* because cpuid <-> apicid mapping is persistent now.
*/
if (invalid_logical_cpuid(pr->id) || !cpu_present(pr->id)) {
- int ret = acpi_processor_hotadd_init(pr);
+ int ret = acpi_processor_hotadd_init(pr, device);
if (ret)
return ret;
+ } else {
+ if (!acpi_processor_set_per_cpu(pr, device))
+ return -EINVAL;
}
/*
@@ -365,8 +407,6 @@ static int acpi_processor_get_info(struct acpi_device *device)
* (cpu_data(cpu)) values, like CPU feature flags, family, model, etc.
* Such things have to be put in and set up by the processor driver's .probe().
*/
-static DEFINE_PER_CPU(void *, processor_device_array);
-
static int acpi_processor_add(struct acpi_device *device,
const struct acpi_device_id *id)
{
@@ -395,28 +435,6 @@ static int acpi_processor_add(struct acpi_device *device,
if (result) /* Processor is not physically present or unavailable */
goto err_clear_driver_data;
- BUG_ON(pr->id >= nr_cpu_ids);
-
- /*
- * Buggy BIOS check.
- * ACPI id of processors can be reported wrongly by the BIOS.
- * Don't trust it blindly
- */
- if (per_cpu(processor_device_array, pr->id) != NULL &&
- per_cpu(processor_device_array, pr->id) != device) {
- dev_warn(&device->dev,
- "BIOS reported wrong ACPI id %d for the processor\n",
- pr->id);
- /* Give up, but do not abort the namespace scan. */
- goto err_clear_driver_data;
- }
- /*
- * processor_device_array is not cleared on errors to allow buggy BIOS
- * checks.
- */
- per_cpu(processor_device_array, pr->id) = device;
- per_cpu(processors, pr->id) = pr;
-
dev = get_cpu_device(pr->id);
if (!dev) {
result = -ENODEV;
@@ -470,10 +488,6 @@ static void acpi_processor_remove(struct acpi_device *device)
device_release_driver(pr->dev);
acpi_unbind_one(pr->dev);
- /* Clean up. */
- per_cpu(processor_device_array, pr->id) = NULL;
- per_cpu(processors, pr->id) = NULL;
-
cpu_maps_update_begin();
cpus_write_lock();
@@ -481,6 +495,10 @@ static void acpi_processor_remove(struct acpi_device *device)
arch_unregister_cpu(pr->id);
acpi_unmap_cpu(pr->id);
+ /* Clean up. */
+ per_cpu(processor_device_array, pr->id) = NULL;
+ per_cpu(processors, pr->id) = NULL;
+
cpus_write_unlock();
cpu_maps_update_done();
--
2.39.2On Tue, Apr 30, 2024 at 4:27 PM Jonathan Cameron
<Jonathan.Cameron@huawei.com> wrote:
>
> Make the per_cpu(processors, cpu) entries available earlier so that
> they are available in arch_register_cpu() as ARM64 will need access
> to the acpi_handle to distinguish between acpi_processor_add()
> and earlier registration attempts (which will fail as _STA cannot
> be checked).
>
> Reorder the remove flow to clear this per_cpu() after
> arch_unregister_cpu() has completed, allowing it to be used in
> there as well.
>
> Note that on x86 for the CPU hotplug case, the pr->id prior to
> acpi_map_cpu() may be invalid. Thus the per_cpu() structures
> must be initialized after that call or after checking the ID
> is valid (not hotplug path).
>
> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
One nit below.
> ---
> v9: Add back a blank line accidentally removed in code move.
> Fix up error returns so that the new cleanup in processor_add()
> is triggered on detection of the bios bug.
> Combined with the previous 2 patches, should solve the leak
> that Gavin identified.
> ---
> drivers/acpi/acpi_processor.c | 80 +++++++++++++++++++++--------------
> 1 file changed, 49 insertions(+), 31 deletions(-)
>
> diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c
> index 16e36e55a560..4a79b42d649e 100644
> --- a/drivers/acpi/acpi_processor.c
> +++ b/drivers/acpi/acpi_processor.c
> @@ -183,8 +183,38 @@ static void __init acpi_pcc_cpufreq_init(void) {}
> #endif /* CONFIG_X86 */
>
> /* Initialization */
> +static DEFINE_PER_CPU(void *, processor_device_array);
> +
> +static bool acpi_processor_set_per_cpu(struct acpi_processor *pr,
> + struct acpi_device *device)
> +{
> + BUG_ON(pr->id >= nr_cpu_ids);
> +
> + /*
> + * Buggy BIOS check.
> + * ACPI id of processors can be reported wrongly by the BIOS.
> + * Don't trust it blindly
> + */
> + if (per_cpu(processor_device_array, pr->id) != NULL &&
> + per_cpu(processor_device_array, pr->id) != device) {
> + dev_warn(&device->dev,
> + "BIOS reported wrong ACPI id %d for the processor\n",
> + pr->id);
> + return false;
> + }
> + /*
> + * processor_device_array is not cleared on errors to allow buggy BIOS
> + * checks.
> + */
> + per_cpu(processor_device_array, pr->id) = device;
> + per_cpu(processors, pr->id) = pr;
> +
> + return true;
> +}
> +
> #ifdef CONFIG_ACPI_HOTPLUG_CPU
> -static int acpi_processor_hotadd_init(struct acpi_processor *pr)
> +static int acpi_processor_hotadd_init(struct acpi_processor *pr,
> + struct acpi_device *device)
> {
> int ret;
>
> @@ -198,8 +228,16 @@ static int acpi_processor_hotadd_init(struct acpi_processor *pr)
> if (ret)
> goto out;
>
> + if (!acpi_processor_set_per_cpu(pr, device)) {
> + ret = -EINVAL;
> + acpi_unmap_cpu(pr->id);
> + goto out;
> + }
> +
> ret = arch_register_cpu(pr->id);
> if (ret) {
> + /* Leave the processor device array in place to detect buggy bios */
> + per_cpu(processors, pr->id) = NULL;
> acpi_unmap_cpu(pr->id);
> goto out;
> }
> @@ -217,7 +255,8 @@ static int acpi_processor_hotadd_init(struct acpi_processor *pr)
> return ret;
> }
> #else
> -static inline int acpi_processor_hotadd_init(struct acpi_processor *pr)
> +static inline int acpi_processor_hotadd_init(struct acpi_processor *pr,
> + struct acpi_device *device)
> {
> return -ENODEV;
> }
> @@ -316,10 +355,13 @@ static int acpi_processor_get_info(struct acpi_device *device)
> * because cpuid <-> apicid mapping is persistent now.
> */
> if (invalid_logical_cpuid(pr->id) || !cpu_present(pr->id)) {
> - int ret = acpi_processor_hotadd_init(pr);
> + int ret = acpi_processor_hotadd_init(pr, device);
>
> if (ret)
> return ret;
> + } else {
> + if (!acpi_processor_set_per_cpu(pr, device))
> + return -EINVAL;
> }
This looks a bit odd.
I would make acpi_processor_set_per_cpu() return 0 on success and
-EINVAL on failure and the above would become
if (invalid_logical_cpuid(pr->id) || !cpu_present(pr->id))
ret = acpi_processor_hotadd_init(pr, device);
else
ret = acpi_processor_set_per_cpu(pr, device);
if (ret)
return ret;
(and of course ret needs to be defined at the beginning of the function).
>
> /*
> @@ -365,8 +407,6 @@ static int acpi_processor_get_info(struct acpi_device *device)
> * (cpu_data(cpu)) values, like CPU feature flags, family, model, etc.
> * Such things have to be put in and set up by the processor driver's .probe().
> */
> -static DEFINE_PER_CPU(void *, processor_device_array);
> -
> static int acpi_processor_add(struct acpi_device *device,
> const struct acpi_device_id *id)
> {
> @@ -395,28 +435,6 @@ static int acpi_processor_add(struct acpi_device *device,
> if (result) /* Processor is not physically present or unavailable */
> goto err_clear_driver_data;
>
> - BUG_ON(pr->id >= nr_cpu_ids);
> -
> - /*
> - * Buggy BIOS check.
> - * ACPI id of processors can be reported wrongly by the BIOS.
> - * Don't trust it blindly
> - */
> - if (per_cpu(processor_device_array, pr->id) != NULL &&
> - per_cpu(processor_device_array, pr->id) != device) {
> - dev_warn(&device->dev,
> - "BIOS reported wrong ACPI id %d for the processor\n",
> - pr->id);
> - /* Give up, but do not abort the namespace scan. */
> - goto err_clear_driver_data;
> - }
> - /*
> - * processor_device_array is not cleared on errors to allow buggy BIOS
> - * checks.
> - */
> - per_cpu(processor_device_array, pr->id) = device;
> - per_cpu(processors, pr->id) = pr;
> -
> dev = get_cpu_device(pr->id);
> if (!dev) {
> result = -ENODEV;
> @@ -470,10 +488,6 @@ static void acpi_processor_remove(struct acpi_device *device)
> device_release_driver(pr->dev);
> acpi_unbind_one(pr->dev);
>
> - /* Clean up. */
> - per_cpu(processor_device_array, pr->id) = NULL;
> - per_cpu(processors, pr->id) = NULL;
> -
> cpu_maps_update_begin();
> cpus_write_lock();
>
> @@ -481,6 +495,10 @@ static void acpi_processor_remove(struct acpi_device *device)
> arch_unregister_cpu(pr->id);
> acpi_unmap_cpu(pr->id);
>
> + /* Clean up. */
> + per_cpu(processor_device_array, pr->id) = NULL;
> + per_cpu(processors, pr->id) = NULL;
> +
> cpus_write_unlock();
> cpu_maps_update_done();
>
> --
> 2.39.2
>
On Tue, 7 May 2024 21:04:26 +0200
"Rafael J. Wysocki" <rafael@kernel.org> wrote:
> On Tue, Apr 30, 2024 at 4:27 PM Jonathan Cameron
> <Jonathan.Cameron@huawei.com> wrote:
> >
> > Make the per_cpu(processors, cpu) entries available earlier so that
> > they are available in arch_register_cpu() as ARM64 will need access
> > to the acpi_handle to distinguish between acpi_processor_add()
> > and earlier registration attempts (which will fail as _STA cannot
> > be checked).
> >
> > Reorder the remove flow to clear this per_cpu() after
> > arch_unregister_cpu() has completed, allowing it to be used in
> > there as well.
> >
> > Note that on x86 for the CPU hotplug case, the pr->id prior to
> > acpi_map_cpu() may be invalid. Thus the per_cpu() structures
> > must be initialized after that call or after checking the ID
> > is valid (not hotplug path).
> >
> > Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
>
> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
>
> One nit below.
Thanks. Given timing, this is looking like 6.11 material.
I'll tidy this up and post a v10 in a couple of weeks (so around
rc1 time). Maybe we'll pick up some more tags for the ARM
specific bits in the meantime.
Thanks for all your help!
Jonathan
>
> > ---
> > v9: Add back a blank line accidentally removed in code move.
> > Fix up error returns so that the new cleanup in processor_add()
> > is triggered on detection of the bios bug.
> > Combined with the previous 2 patches, should solve the leak
> > that Gavin identified.
> > ---
> > drivers/acpi/acpi_processor.c | 80 +++++++++++++++++++++--------------
> > 1 file changed, 49 insertions(+), 31 deletions(-)
> >
> > diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c
> > index 16e36e55a560..4a79b42d649e 100644
> > --- a/drivers/acpi/acpi_processor.c
> > +++ b/drivers/acpi/acpi_processor.c
> > @@ -183,8 +183,38 @@ static void __init acpi_pcc_cpufreq_init(void) {}
> > #endif /* CONFIG_X86 */
> >
> > /* Initialization */
> > +static DEFINE_PER_CPU(void *, processor_device_array);
> > +
> > +static bool acpi_processor_set_per_cpu(struct acpi_processor *pr,
> > + struct acpi_device *device)
> > +{
> > + BUG_ON(pr->id >= nr_cpu_ids);
> > +
> > + /*
> > + * Buggy BIOS check.
> > + * ACPI id of processors can be reported wrongly by the BIOS.
> > + * Don't trust it blindly
> > + */
> > + if (per_cpu(processor_device_array, pr->id) != NULL &&
> > + per_cpu(processor_device_array, pr->id) != device) {
> > + dev_warn(&device->dev,
> > + "BIOS reported wrong ACPI id %d for the processor\n",
> > + pr->id);
> > + return false;
> > + }
> > + /*
> > + * processor_device_array is not cleared on errors to allow buggy BIOS
> > + * checks.
> > + */
> > + per_cpu(processor_device_array, pr->id) = device;
> > + per_cpu(processors, pr->id) = pr;
> > +
> > + return true;
> > +}
> > +
> > #ifdef CONFIG_ACPI_HOTPLUG_CPU
> > -static int acpi_processor_hotadd_init(struct acpi_processor *pr)
> > +static int acpi_processor_hotadd_init(struct acpi_processor *pr,
> > + struct acpi_device *device)
> > {
> > int ret;
> >
> > @@ -198,8 +228,16 @@ static int acpi_processor_hotadd_init(struct acpi_processor *pr)
> > if (ret)
> > goto out;
> >
> > + if (!acpi_processor_set_per_cpu(pr, device)) {
> > + ret = -EINVAL;
> > + acpi_unmap_cpu(pr->id);
> > + goto out;
> > + }
> > +
> > ret = arch_register_cpu(pr->id);
> > if (ret) {
> > + /* Leave the processor device array in place to detect buggy bios */
> > + per_cpu(processors, pr->id) = NULL;
> > acpi_unmap_cpu(pr->id);
> > goto out;
> > }
> > @@ -217,7 +255,8 @@ static int acpi_processor_hotadd_init(struct acpi_processor *pr)
> > return ret;
> > }
> > #else
> > -static inline int acpi_processor_hotadd_init(struct acpi_processor *pr)
> > +static inline int acpi_processor_hotadd_init(struct acpi_processor *pr,
> > + struct acpi_device *device)
> > {
> > return -ENODEV;
> > }
> > @@ -316,10 +355,13 @@ static int acpi_processor_get_info(struct acpi_device *device)
> > * because cpuid <-> apicid mapping is persistent now.
> > */
> > if (invalid_logical_cpuid(pr->id) || !cpu_present(pr->id)) {
> > - int ret = acpi_processor_hotadd_init(pr);
> > + int ret = acpi_processor_hotadd_init(pr, device);
> >
> > if (ret)
> > return ret;
> > + } else {
> > + if (!acpi_processor_set_per_cpu(pr, device))
> > + return -EINVAL;
> > }
>
> This looks a bit odd.
>
> I would make acpi_processor_set_per_cpu() return 0 on success and
> -EINVAL on failure and the above would become
>
> if (invalid_logical_cpuid(pr->id) || !cpu_present(pr->id))
> ret = acpi_processor_hotadd_init(pr, device);
> else
> ret = acpi_processor_set_per_cpu(pr, device);
>
> if (ret)
> return ret;
>
> (and of course ret needs to be defined at the beginning of the function).
>
> >
> > /*
> > @@ -365,8 +407,6 @@ static int acpi_processor_get_info(struct acpi_device *device)
> > * (cpu_data(cpu)) values, like CPU feature flags, family, model, etc.
> > * Such things have to be put in and set up by the processor driver's .probe().
> > */
> > -static DEFINE_PER_CPU(void *, processor_device_array);
> > -
> > static int acpi_processor_add(struct acpi_device *device,
> > const struct acpi_device_id *id)
> > {
> > @@ -395,28 +435,6 @@ static int acpi_processor_add(struct acpi_device *device,
> > if (result) /* Processor is not physically present or unavailable */
> > goto err_clear_driver_data;
> >
> > - BUG_ON(pr->id >= nr_cpu_ids);
> > -
> > - /*
> > - * Buggy BIOS check.
> > - * ACPI id of processors can be reported wrongly by the BIOS.
> > - * Don't trust it blindly
> > - */
> > - if (per_cpu(processor_device_array, pr->id) != NULL &&
> > - per_cpu(processor_device_array, pr->id) != device) {
> > - dev_warn(&device->dev,
> > - "BIOS reported wrong ACPI id %d for the processor\n",
> > - pr->id);
> > - /* Give up, but do not abort the namespace scan. */
> > - goto err_clear_driver_data;
> > - }
> > - /*
> > - * processor_device_array is not cleared on errors to allow buggy BIOS
> > - * checks.
> > - */
> > - per_cpu(processor_device_array, pr->id) = device;
> > - per_cpu(processors, pr->id) = pr;
> > -
> > dev = get_cpu_device(pr->id);
> > if (!dev) {
> > result = -ENODEV;
> > @@ -470,10 +488,6 @@ static void acpi_processor_remove(struct acpi_device *device)
> > device_release_driver(pr->dev);
> > acpi_unbind_one(pr->dev);
> >
> > - /* Clean up. */
> > - per_cpu(processor_device_array, pr->id) = NULL;
> > - per_cpu(processors, pr->id) = NULL;
> > -
> > cpu_maps_update_begin();
> > cpus_write_lock();
> >
> > @@ -481,6 +495,10 @@ static void acpi_processor_remove(struct acpi_device *device)
> > arch_unregister_cpu(pr->id);
> > acpi_unmap_cpu(pr->id);
> >
> > + /* Clean up. */
> > + per_cpu(processor_device_array, pr->id) = NULL;
> > + per_cpu(processors, pr->id) = NULL;
> > +
> > cpus_write_unlock();
> > cpu_maps_update_done();
> >
> > --
> > 2.39.2
> >
On 5/1/24 00:24, Jonathan Cameron wrote:
> Make the per_cpu(processors, cpu) entries available earlier so that
> they are available in arch_register_cpu() as ARM64 will need access
> to the acpi_handle to distinguish between acpi_processor_add()
> and earlier registration attempts (which will fail as _STA cannot
> be checked).
>
> Reorder the remove flow to clear this per_cpu() after
> arch_unregister_cpu() has completed, allowing it to be used in
> there as well.
>
> Note that on x86 for the CPU hotplug case, the pr->id prior to
> acpi_map_cpu() may be invalid. Thus the per_cpu() structures
> must be initialized after that call or after checking the ID
> is valid (not hotplug path).
>
> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
>
> ---
> v9: Add back a blank line accidentally removed in code move.
> Fix up error returns so that the new cleanup in processor_add()
> is triggered on detection of the bios bug.
> Combined with the previous 2 patches, should solve the leak
> that Gavin identified.
> ---
> drivers/acpi/acpi_processor.c | 80 +++++++++++++++++++++--------------
> 1 file changed, 49 insertions(+), 31 deletions(-)
>
It would be nice for acpi_processor_set_per_cpu() to return errno,
explained as below. The patch looks good to me in either me.
Reviewed-by: Gavin Shan <gshan@redhat.com>
> diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c
> index 16e36e55a560..4a79b42d649e 100644
> --- a/drivers/acpi/acpi_processor.c
> +++ b/drivers/acpi/acpi_processor.c
> @@ -183,8 +183,38 @@ static void __init acpi_pcc_cpufreq_init(void) {}
> #endif /* CONFIG_X86 */
>
> /* Initialization */
> +static DEFINE_PER_CPU(void *, processor_device_array);
> +
> +static bool acpi_processor_set_per_cpu(struct acpi_processor *pr,
> + struct acpi_device *device)
> +{
> + BUG_ON(pr->id >= nr_cpu_ids);
> +
> + /*
> + * Buggy BIOS check.
> + * ACPI id of processors can be reported wrongly by the BIOS.
> + * Don't trust it blindly
> + */
> + if (per_cpu(processor_device_array, pr->id) != NULL &&
> + per_cpu(processor_device_array, pr->id) != device) {
> + dev_warn(&device->dev,
> + "BIOS reported wrong ACPI id %d for the processor\n",
> + pr->id);
> + return false;
> + }
> + /*
> + * processor_device_array is not cleared on errors to allow buggy BIOS
> + * checks.
> + */
> + per_cpu(processor_device_array, pr->id) = device;
> + per_cpu(processors, pr->id) = pr;
> +
> + return true;
> +}
> +
I think it'd better for acpi_processor_set_per_cpu() to return errno. -EINVAL
is returned if a mismatched ACPI device is found, and 0 is returned on success.
With the improvement, the callers needn't to translate boolen to errno.
> #ifdef CONFIG_ACPI_HOTPLUG_CPU
> -static int acpi_processor_hotadd_init(struct acpi_processor *pr)
> +static int acpi_processor_hotadd_init(struct acpi_processor *pr,
> + struct acpi_device *device)
> {
> int ret;
>
> @@ -198,8 +228,16 @@ static int acpi_processor_hotadd_init(struct acpi_processor *pr)
> if (ret)
> goto out;
>
> + if (!acpi_processor_set_per_cpu(pr, device)) {
> + ret = -EINVAL;
> + acpi_unmap_cpu(pr->id);
> + goto out;
> + }
> +
If errno is returned from acpi_processor_set_per_cpu(), this chunk of code becomes:
ret = acpi_processor_set_per_cpu(pr, device);
if (ret) {
acpi_unmap_cpu(pr->id);
goto out;
}
> ret = arch_register_cpu(pr->id);
> if (ret) {
> + /* Leave the processor device array in place to detect buggy bios */
> + per_cpu(processors, pr->id) = NULL;
> acpi_unmap_cpu(pr->id);
> goto out;
> }
> @@ -217,7 +255,8 @@ static int acpi_processor_hotadd_init(struct acpi_processor *pr)
> return ret;
> }
> #else
> -static inline int acpi_processor_hotadd_init(struct acpi_processor *pr)
> +static inline int acpi_processor_hotadd_init(struct acpi_processor *pr,
> + struct acpi_device *device)
> {
> return -ENODEV;
> }
> @@ -316,10 +355,13 @@ static int acpi_processor_get_info(struct acpi_device *device)
> * because cpuid <-> apicid mapping is persistent now.
> */
> if (invalid_logical_cpuid(pr->id) || !cpu_present(pr->id)) {
> - int ret = acpi_processor_hotadd_init(pr);
> + int ret = acpi_processor_hotadd_init(pr, device);
>
> if (ret)
> return ret;
> + } else {
> + if (!acpi_processor_set_per_cpu(pr, device))
> + return -EINVAL;
> }
>
ret = acpi_processor_set_per_cpu(pr, device);
if (ret)
return ret;
> /*
> @@ -365,8 +407,6 @@ static int acpi_processor_get_info(struct acpi_device *device)
> * (cpu_data(cpu)) values, like CPU feature flags, family, model, etc.
> * Such things have to be put in and set up by the processor driver's .probe().
> */
> -static DEFINE_PER_CPU(void *, processor_device_array);
> -
> static int acpi_processor_add(struct acpi_device *device,
> const struct acpi_device_id *id)
> {
> @@ -395,28 +435,6 @@ static int acpi_processor_add(struct acpi_device *device,
> if (result) /* Processor is not physically present or unavailable */
> goto err_clear_driver_data;
>
> - BUG_ON(pr->id >= nr_cpu_ids);
> -
> - /*
> - * Buggy BIOS check.
> - * ACPI id of processors can be reported wrongly by the BIOS.
> - * Don't trust it blindly
> - */
> - if (per_cpu(processor_device_array, pr->id) != NULL &&
> - per_cpu(processor_device_array, pr->id) != device) {
> - dev_warn(&device->dev,
> - "BIOS reported wrong ACPI id %d for the processor\n",
> - pr->id);
> - /* Give up, but do not abort the namespace scan. */
> - goto err_clear_driver_data;
> - }
> - /*
> - * processor_device_array is not cleared on errors to allow buggy BIOS
> - * checks.
> - */
> - per_cpu(processor_device_array, pr->id) = device;
> - per_cpu(processors, pr->id) = pr;
> -
> dev = get_cpu_device(pr->id);
> if (!dev) {
> result = -ENODEV;
> @@ -470,10 +488,6 @@ static void acpi_processor_remove(struct acpi_device *device)
> device_release_driver(pr->dev);
> acpi_unbind_one(pr->dev);
>
> - /* Clean up. */
> - per_cpu(processor_device_array, pr->id) = NULL;
> - per_cpu(processors, pr->id) = NULL;
> -
> cpu_maps_update_begin();
> cpus_write_lock();
>
> @@ -481,6 +495,10 @@ static void acpi_processor_remove(struct acpi_device *device)
> arch_unregister_cpu(pr->id);
> acpi_unmap_cpu(pr->id);
>
> + /* Clean up. */
> + per_cpu(processor_device_array, pr->id) = NULL;
> + per_cpu(processors, pr->id) = NULL;
> +
> cpus_write_unlock();
> cpu_maps_update_done();
>
Thanks,
Gavin
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