[PATCH v1] ACPI: PM: s2idle: Evaluate all Low-Power S0 Idle _DSM functions

[PATCH v1] ACPI: PM: s2idle: Evaluate all Low-Power S0 Idle _DSM functions

[Rafael J. Wysocki]

From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Commit 073237281a50 ("ACPI: PM: s2idle: Enable Low-Power S0 Idle MSFT
UUID for non-AMD systems") attempted to avoid evaluating the same Low-
Power S0 Idle _DSM functions for different UUIDs, but that turns out to
be a mistake, because some systems in the field are adversely affected
by it.

Address this by allowing  all Low-Power S0 Idle _DSM functions to be
evaluated, but still print the message regarding duplication of Low-
Power S0 Idle _DSM function sets for different UUIDs.

Fixes: 073237281a50 ("ACPI: PM: s2idle: Enable Low-Power S0 Idle MSFT UUID for non-AMD systems")
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218750
Reported-and-tested-by: Mark Pearson <mpearson@lenovo.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---
 drivers/acpi/x86/s2idle.c |    8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

Index: linux-pm/drivers/acpi/x86/s2idle.c
===================================================================
--- linux-pm.orig/drivers/acpi/x86/s2idle.c
+++ linux-pm/drivers/acpi/x86/s2idle.c
@@ -492,16 +492,14 @@ static int lps0_device_attach(struct acp
 			unsigned int func_mask;
 
 			/*
-			 * Avoid evaluating the same _DSM function for two
-			 * different UUIDs and prioritize the MSFT one.
+			 * Log a message if the _DSM function sets for two
+			 * different UUIDs overlap.
 			 */
 			func_mask = lps0_dsm_func_mask & lps0_dsm_func_mask_microsoft;
-			if (func_mask) {
+			if (func_mask)
 				acpi_handle_info(adev->handle,
 						 "Duplicate LPS0 _DSM functions (mask: 0x%x)\n",
 						 func_mask);
-				lps0_dsm_func_mask &= ~func_mask;
-			}
 		}
 	}
 

Re: [PATCH v1] ACPI: PM: s2idle: Evaluate all Low-Power S0 Idle _DSM functions

[Mario Limonciello]

On 4/23/2024 14:19, Rafael J. Wysocki wrote:
> From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> 
> Commit 073237281a50 ("ACPI: PM: s2idle: Enable Low-Power S0 Idle MSFT
> UUID for non-AMD systems") attempted to avoid evaluating the same Low-
> Power S0 Idle _DSM functions for different UUIDs, but that turns out to
> be a mistake, because some systems in the field are adversely affected
> by it.
> 
> Address this by allowing  all Low-Power S0 Idle _DSM functions to be
> evaluated, but still print the message regarding duplication of Low-
> Power S0 Idle _DSM function sets for different UUIDs.
> 
> Fixes: 073237281a50 ("ACPI: PM: s2idle: Enable Low-Power S0 Idle MSFT UUID for non-AMD systems")
> Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218750
> Reported-and-tested-by: Mark Pearson <mpearson@lenovo.com>
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Ah glad to hear that my idea worked.  FWIW we saw the same type of issue 
on some AMD systems when we first introduced the MSFT UUID.

Suggested-by: Mario Limonciello <mario.limonciello@amd.com>
Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>

> ---
>   drivers/acpi/x86/s2idle.c |    8 +++-----
>   1 file changed, 3 insertions(+), 5 deletions(-)
> 
> Index: linux-pm/drivers/acpi/x86/s2idle.c
> ===================================================================
> --- linux-pm.orig/drivers/acpi/x86/s2idle.c
> +++ linux-pm/drivers/acpi/x86/s2idle.c
> @@ -492,16 +492,14 @@ static int lps0_device_attach(struct acp
>   			unsigned int func_mask;
>   
>   			/*
> -			 * Avoid evaluating the same _DSM function for two
> -			 * different UUIDs and prioritize the MSFT one.
> +			 * Log a message if the _DSM function sets for two
> +			 * different UUIDs overlap.
>   			 */
>   			func_mask = lps0_dsm_func_mask & lps0_dsm_func_mask_microsoft;
> -			if (func_mask) {
> +			if (func_mask)
>   				acpi_handle_info(adev->handle,
>   						 "Duplicate LPS0 _DSM functions (mask: 0x%x)\n",
>   						 func_mask);
> -				lps0_dsm_func_mask &= ~func_mask;
> -			}
>   		}
>   	}
>   
> 
> 
> 

Re: [PATCH v1] ACPI: PM: s2idle: Evaluate all Low-Power S0 Idle _DSM functions

[Rafael J. Wysocki]

On Tue, Apr 23, 2024 at 9:40 PM Mario Limonciello
<mario.limonciello@amd.com> wrote:
>
> On 4/23/2024 14:19, Rafael J. Wysocki wrote:
> > From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> >
> > Commit 073237281a50 ("ACPI: PM: s2idle: Enable Low-Power S0 Idle MSFT
> > UUID for non-AMD systems") attempted to avoid evaluating the same Low-
> > Power S0 Idle _DSM functions for different UUIDs, but that turns out to
> > be a mistake, because some systems in the field are adversely affected
> > by it.
> >
> > Address this by allowing  all Low-Power S0 Idle _DSM functions to be
> > evaluated, but still print the message regarding duplication of Low-
> > Power S0 Idle _DSM function sets for different UUIDs.
> >
> > Fixes: 073237281a50 ("ACPI: PM: s2idle: Enable Low-Power S0 Idle MSFT UUID for non-AMD systems")
> > Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218750
> > Reported-and-tested-by: Mark Pearson <mpearson@lenovo.com>
> > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
>
> Ah glad to hear that my idea worked.

We've arrived at the same solution independently, I've only looked at
the BZ when the patch was ready to send.

> FWIW we saw the same type of issue
> on some AMD systems when we first introduced the MSFT UUID.
>
> Suggested-by: Mario Limonciello <mario.limonciello@amd.com>

But sure.

> Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>

Thanks!

> > ---
> >   drivers/acpi/x86/s2idle.c |    8 +++-----
> >   1 file changed, 3 insertions(+), 5 deletions(-)
> >
> > Index: linux-pm/drivers/acpi/x86/s2idle.c
> > ===================================================================
> > --- linux-pm.orig/drivers/acpi/x86/s2idle.c
> > +++ linux-pm/drivers/acpi/x86/s2idle.c
> > @@ -492,16 +492,14 @@ static int lps0_device_attach(struct acp
> >                       unsigned int func_mask;
> >
> >                       /*
> > -                      * Avoid evaluating the same _DSM function for two
> > -                      * different UUIDs and prioritize the MSFT one.
> > +                      * Log a message if the _DSM function sets for two
> > +                      * different UUIDs overlap.
> >                        */
> >                       func_mask = lps0_dsm_func_mask & lps0_dsm_func_mask_microsoft;
> > -                     if (func_mask) {
> > +                     if (func_mask)
> >                               acpi_handle_info(adev->handle,
> >                                                "Duplicate LPS0 _DSM functions (mask: 0x%x)\n",
> >                                                func_mask);
> > -                             lps0_dsm_func_mask &= ~func_mask;
> > -                     }
> >               }
> >       }
> >
> >
> >
> >
>