| Message ID | 1397150061-29735-6-git-send-email-imammedo@redhat.com (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
* Igor Mammedov <imammedo@redhat.com> wrote: > acpi_processor_add() assumes that present at boot CPUs > are always onlined, it is not so if a CPU failed to become > onlined. As result acpi_processor_add() will mark such CPU > device as onlined in sysfs and following attempts to > online/offline it using /sys/device/system/cpu/cpuX/online > attribute will fail. > > Do not poke into device internals in acpi_processor_add() > and touch "struct device { .offline }" attribute, since > for CPUs onlined at boot it's set by: > topology_init() -> arch_register_cpu() -> register_cpu() > before ACPI device tree is parsed, and for hotplugged > CPUs it's set when userspace onlines CPU via sysfs. > > Signed-off-by: Igor Mammedov <imammedo@redhat.com> > --- > drivers/acpi/acpi_processor.c | 3 --- > 1 files changed, 0 insertions(+), 3 deletions(-) Can this fix be moved first too, or does it have undesirable side effects on unmodified kernels? Thanks, Ingo -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Monday, April 14, 2014 11:21:47 AM Ingo Molnar wrote: > > * Igor Mammedov <imammedo@redhat.com> wrote: > > > acpi_processor_add() assumes that present at boot CPUs > > are always onlined, it is not so if a CPU failed to become > > onlined. As result acpi_processor_add() will mark such CPU > > device as onlined in sysfs and following attempts to > > online/offline it using /sys/device/system/cpu/cpuX/online > > attribute will fail. > > > > Do not poke into device internals in acpi_processor_add() > > and touch "struct device { .offline }" attribute, since > > for CPUs onlined at boot it's set by: > > topology_init() -> arch_register_cpu() -> register_cpu() > > before ACPI device tree is parsed, and for hotplugged > > CPUs it's set when userspace onlines CPU via sysfs. > > > > Signed-off-by: Igor Mammedov <imammedo@redhat.com> > > --- > > drivers/acpi/acpi_processor.c | 3 --- > > 1 files changed, 0 insertions(+), 3 deletions(-) > > Can this fix be moved first too, or does it have undesirable side > effects on unmodified kernels? This patch is not correct. Rafael -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thursday, April 10, 2014 07:14:21 PM Igor Mammedov wrote: > acpi_processor_add() assumes that present at boot CPUs > are always onlined, it is not so if a CPU failed to become > onlined. What do you mean by that? What *exactly* is the failure scenario? > As result acpi_processor_add() will mark such CPU > device as onlined in sysfs and following attempts to > online/offline it using /sys/device/system/cpu/cpuX/online > attribute will fail. > > Do not poke into device internals in acpi_processor_add() > and touch "struct device { .offline }" attribute, since > for CPUs onlined at boot it's set by: > topology_init() -> arch_register_cpu() -> register_cpu() > before ACPI device tree is parsed, and for hotplugged > CPUs it's set when userspace onlines CPU via sysfs. > > Signed-off-by: Igor Mammedov <imammedo@redhat.com> > --- > drivers/acpi/acpi_processor.c | 3 --- > 1 files changed, 0 insertions(+), 3 deletions(-) > > diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c > index c29c2c3..d56e4b4 100644 > --- a/drivers/acpi/acpi_processor.c > +++ b/drivers/acpi/acpi_processor.c > @@ -403,9 +403,6 @@ static int acpi_processor_add(struct acpi_device *device, > if (result) > goto err; > > - pr->dev = dev; The line above has to stay as is. > - dev->offline = pr->flags.need_hotplug_init; > - > /* Trigger the processor driver's .probe() if present. */ > if (device_attach(dev) >= 0) > return 1; >
diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c index c29c2c3..d56e4b4 100644 --- a/drivers/acpi/acpi_processor.c +++ b/drivers/acpi/acpi_processor.c @@ -403,9 +403,6 @@ static int acpi_processor_add(struct acpi_device *device, if (result) goto err; - pr->dev = dev; - dev->offline = pr->flags.need_hotplug_init; - /* Trigger the processor driver's .probe() if present. */ if (device_attach(dev) >= 0) return 1;
acpi_processor_add() assumes that present at boot CPUs are always onlined, it is not so if a CPU failed to become onlined. As result acpi_processor_add() will mark such CPU device as onlined in sysfs and following attempts to online/offline it using /sys/device/system/cpu/cpuX/online attribute will fail. Do not poke into device internals in acpi_processor_add() and touch "struct device { .offline }" attribute, since for CPUs onlined at boot it's set by: topology_init() -> arch_register_cpu() -> register_cpu() before ACPI device tree is parsed, and for hotplugged CPUs it's set when userspace onlines CPU via sysfs. Signed-off-by: Igor Mammedov <imammedo@redhat.com> --- drivers/acpi/acpi_processor.c | 3 --- 1 files changed, 0 insertions(+), 3 deletions(-)