Re: [PATCH 3/4] ACPI: PCC: Free channel on OpRegion deactivation

From: lihuisong (C)

Date: Tue Jul 21 2026 - 22:52:55 EST



On 7/17/2026 4:10 PM, Sudeep Holla wrote:
ACPICA calls the address space setup callback with
ACPI_REGION_DEACTIVATE when a PCC OperationRegion is torn down.

The PCC setup callback currently allocates a fresh pcc_data and requests
the mailbox channel before looking at the function argument. If ACPICA
deactivates a region, this can leave the existing region context and
mailbox channel unreleased, and may also request a channel during
teardown.

Handle ACPI_REGION_DEACTIVATE before allocation. Free the PCC mailbox
channel, release the region context and clear the context pointer.

Fixes: 77e2a04745ff ("ACPI: PCC: Implement OperationRegion handler for the PCC Type 3 subtype")
Signed-off-by: Sudeep Holla <sudeep.holla@xxxxxxxxxx>
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How to trigger this region deactivate at runtime?

Overall looks good to me.
Reviewed-by: Huisong Li <lihuisong@xxxxxxxxxx>