From: Woody Suwalski <[email protected]>
Add and ACPI idle power level limit for 32-bit ThinkPad T40.
There is a regression on T40 introduced by commit d6b88ce2, starting
with kernel 5.16:
commit d6b88ce2eb9d2698eb24451eb92c0a1649b17bb1
Author: Richard Gong <[email protected]>
Date: Wed Sep 22 08:31:16 2021 -0500
ACPI: processor idle: Allow playing dead in C3 state
The above patch is trying to enter C3 state during init, what is causing
a T40 system freeze. I have not found a similar issue on any other of my
32-bit machines.
The fix is to add another exception to the processor_power_dmi_table[] list.
As a result the dmesg shows as expected:
2.155398] ACPI: IBM ThinkPad T40 detected - limiting to C2
max_cstate. Override with "processor.max_cstate=9"
[ 2.155404] ACPI: processor limited to max C-state 2
The fix is trivial and affects only vintage T40 systems.
Signed-off-by: Woody Suwalski <[email protected]>
---
--- a/drivers/acpi/processor_idle.c 2022-02-04 09:09:54.515906362 -0500
+++ b/drivers/acpi/processor_idle.c 2022-02-04 14:21:08.264911271 -0500
@@ -96,6 +96,11 @@ static const struct dmi_system_id proces
DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
DMI_MATCH(DMI_PRODUCT_NAME,"L8400B series Notebook PC")},
(void *)1},
+ /* T40 can not handle C3 idle state */
+ { set_max_cstate, "IBM ThinkPad T40", {
+ DMI_MATCH(DMI_SYS_VENDOR, "IBM"),
+ DMI_MATCH(DMI_PRODUCT_NAME, "23737CU")},
+ (void *)2},
{},
};
Hi,
On 2/9/22 22:05, Woody Suwalski wrote:
> From: Woody Suwalski <[email protected]>
>
> Add and ACPI idle power level limit for 32-bit ThinkPad T40.
>
> There is a regression on T40 introduced by commit d6b88ce2, starting with kernel 5.16:
>
> commit d6b88ce2eb9d2698eb24451eb92c0a1649b17bb1
> Author: Richard Gong <[email protected]>
> Date: Wed Sep 22 08:31:16 2021 -0500
>
> ACPI: processor idle: Allow playing dead in C3 state
>
> The above patch is trying to enter C3 state during init, what is causing a T40 system freeze. I have not found a similar issue on any other of my 32-bit machines.
>
> The fix is to add another exception to the processor_power_dmi_table[] list.
> As a result the dmesg shows as expected:
>
> 2.155398] ACPI: IBM ThinkPad T40 detected - limiting to C2 max_cstate. Override with "processor.max_cstate=9"
> [ 2.155404] ACPI: processor limited to max C-state 2
>
> The fix is trivial and affects only vintage T40 systems.
>
> Signed-off-by: Woody Suwalski <[email protected]>
> ---
Thanks, patch looks good to me:
Reviewed-by: Hans de Goede <[email protected]>
Regards,
Hans
> --- a/drivers/acpi/processor_idle.c 2022-02-04 09:09:54.515906362 -0500
> +++ b/drivers/acpi/processor_idle.c 2022-02-04 14:21:08.264911271 -0500
> @@ -96,6 +96,11 @@ static const struct dmi_system_id proces
> DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
> DMI_MATCH(DMI_PRODUCT_NAME,"L8400B series Notebook PC")},
> (void *)1},
> + /* T40 can not handle C3 idle state */
> + { set_max_cstate, "IBM ThinkPad T40", {
> + DMI_MATCH(DMI_SYS_VENDOR, "IBM"),
> + DMI_MATCH(DMI_PRODUCT_NAME, "23737CU")},
> + (void *)2},
> {},
> };
>
>
On Mon, Feb 14, 2022 at 12:32 PM Hans de Goede <[email protected]> wrote:
>
> Hi,
>
> On 2/9/22 22:05, Woody Suwalski wrote:
> > From: Woody Suwalski <[email protected]>
> >
> > Add and ACPI idle power level limit for 32-bit ThinkPad T40.
> >
> > There is a regression on T40 introduced by commit d6b88ce2, starting with kernel 5.16:
> >
> > commit d6b88ce2eb9d2698eb24451eb92c0a1649b17bb1
> > Author: Richard Gong <[email protected]>
> > Date: Wed Sep 22 08:31:16 2021 -0500
> >
> > ACPI: processor idle: Allow playing dead in C3 state
> >
> > The above patch is trying to enter C3 state during init, what is causing a T40 system freeze. I have not found a similar issue on any other of my 32-bit machines.
> >
> > The fix is to add another exception to the processor_power_dmi_table[] list.
> > As a result the dmesg shows as expected:
> >
> > 2.155398] ACPI: IBM ThinkPad T40 detected - limiting to C2 max_cstate. Override with "processor.max_cstate=9"
> > [ 2.155404] ACPI: processor limited to max C-state 2
> >
> > The fix is trivial and affects only vintage T40 systems.
> >
> > Signed-off-by: Woody Suwalski <[email protected]>
> > ---
>
> Thanks, patch looks good to me:
>
> Reviewed-by: Hans de Goede <[email protected]>
>
> Regards,
>
> Hans
>
>
> > --- a/drivers/acpi/processor_idle.c 2022-02-04 09:09:54.515906362 -0500
> > +++ b/drivers/acpi/processor_idle.c 2022-02-04 14:21:08.264911271 -0500
> > @@ -96,6 +96,11 @@ static const struct dmi_system_id proces
> > DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
> > DMI_MATCH(DMI_PRODUCT_NAME,"L8400B series Notebook PC")},
> > (void *)1},
> > + /* T40 can not handle C3 idle state */
> > + { set_max_cstate, "IBM ThinkPad T40", {
> > + DMI_MATCH(DMI_SYS_VENDOR, "IBM"),
> > + DMI_MATCH(DMI_PRODUCT_NAME, "23737CU")},
> > + (void *)2},
> > {},
> > };
Applied as a fix for 5.17-rc5, thanks!