Re: [PATCH v2.1 2/8] ACPI: bus: Rework printing debug messages on _OSC errors

From: Jonathan Cameron

Date: Tue Dec 23 2025 - 06:13:35 EST


On Mon, 22 Dec 2025 20:11:08 +0100
"Rafael J. Wysocki" <rafael@xxxxxxxxxx> wrote:

> From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
>
> Instead of using one function, acpi_print_osc_error(), for printing a
> debug message and dumping the _OSC request data in one go, use
> acpi_handle_debug() directly for printing messages and a separate
> function called acpi_dump_osc_data() for dumping the _OSC request data
> before printing one or more of them.
>
> This avoids
> * dumping _OSC request data multiple times when there are
> multiple error bits set in the return buffer,
> * wrapping message lines on terminals with 80 character line width,
> * mixing up unrelated messages by printing full lines only,
> and generally helps to make the messages easier to parse.
>
> Also, use %pUL for UUID printing instead of printing UUIDs as strings
> and include the revision number into the dumped _OSC request data.
>
> This is how the debug printout looks like when the
> OSC_REQUEST_ERROR and OSC_INVALID_REVISION_ERROR bits
> are set in the return buffer before the change:
>
> ACPI: \_SB_: ACPI: (0811B06E-4A27-44F9-8D60-3CBBC22E7B48): _OSC request failed
> ACPI: _OSC request data:
> ACPI: 1
> ACPI: 2e7eff
> ACPI:
> ACPI: \_SB_: ACPI: (0811B06E-4A27-44F9-8D60-3CBBC22E7B48): _OSC invalid revision
> ACPI: _OSC request data:
> ACPI: 1
> ACPI: 2e7eff
> ACPI:
>
> and this is how it is going to look like afterward:
>
> ACPI: \_SB_: ACPI: _OSC: UUID: 0811B06E-4A27-44F9-8D60-3CBBC22E7B48, rev: 1
> ACPI: \_SB_: ACPI: _OSC: capabilities DWORD 0: [00000001]
> ACPI: \_SB_: ACPI: _OSC: capabilities DWORD 1: [002e7eff]
> ACPI: \_SB_: ACPI: _OSC: request failed
> ACPI: \_SB_: ACPI: _OSC: invalid revision
>
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Reviewed-by: Jonathan Cameron <jonathan.cameron@xxxxxxxxxx>