Commit 3a391a39 authored by Rafael J. Wysocki's avatar Rafael J. Wysocki

ACPI / scan: Do not try to attach scan handlers to devices having them

In acpi_bus_device_attach(), if there is an ACPI device object
for the given handle and that device object has a scan handler
attached to it already, there's nothing more to do for that handle.
Moreover, if acpi_scan_attach_handler() is called then, it may
execute the .attach() callback of the ACPI scan handler already
attached to the device object and that may lead to interesting
breakage.

For this reason, make acpi_bus_device_attach() return success
immediately when the handle's device object has a scan handler
attached to it.
Reported-by: default avatarToshi Kani <toshi.kani@hp.com>
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: default avatarToshi Kani <toshi.kani@hp.com>
Cc: 3.10+ <stable@vger.kernel.org>
parent ad81f054
...@@ -1981,6 +1981,9 @@ static acpi_status acpi_bus_device_attach(acpi_handle handle, u32 lvl_not_used, ...@@ -1981,6 +1981,9 @@ static acpi_status acpi_bus_device_attach(acpi_handle handle, u32 lvl_not_used,
if (acpi_bus_get_device(handle, &device)) if (acpi_bus_get_device(handle, &device))
return AE_CTRL_DEPTH; return AE_CTRL_DEPTH;
if (device->handler)
return AE_OK;
ret = acpi_scan_attach_handler(device); ret = acpi_scan_attach_handler(device);
if (ret) if (ret)
return ret > 0 ? AE_OK : AE_CTRL_DEPTH; return ret > 0 ? AE_OK : AE_CTRL_DEPTH;
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment