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| author | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2017-04-01 00:45:52 +0200 |
|---|---|---|
| committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2017-04-01 00:55:22 +0200 |
| commit | fdad4e7a876a2cb3d2c1f04e5418c324e79fffef (patch) | |
| tree | f3f98b0dc7c36b056c16a7378860d922db47af97 | |
| parent | c02ed2e75ef4c74e41e421acb4ef1494671585e8 (diff) | |
| download | linux-fdad4e7a876a2cb3d2c1f04e5418c324e79fffef.tar.bz2 | |
ACPI / scan: Prefer devices without _HID for _ADR matching
Commit c2a6bbaf0c5f (ACPI / scan: Prefer devices without _HID/_CID
for _ADR matching) added a list_empty(&adev->pnp.ids) check to
find_child_checks() so as to catch situations in which the ACPI
core attempts to decode _ADR for a device having a _HID too which
is strictly against the spec. However, it overlooked the fact that
the adev->pnp.ids list for the devices taken into account by
find_child_checks() may contain device IDs set internally by the
kernel, like "LNXVIDEO" (thanks to Zhang Rui for that realization),
and it broke the enumeration of those devices as a result.
To unbreak it, replace the overly coarse grained list_empty()
check with a much more precise check against the pnp.type.platform_id
flag which is only set for devices having a _HID (that's how it
should be done from the start, as having both _ADR and _CID is
actually permitted).
Fixes: c2a6bbaf0c5f (ACPI / scan: Prefer devices without _HID/_CID for _ADR matching)
Link: https://bugzilla.kernel.org/show_bug.cgi?id=194889
Reported-and-tested-by: Mike <mike@mikewilson.me.uk>
Tested-by: Hans de Goede <hdegoede@redhat.com>
Cc: 4.10+ <stable@vger.kernel.org> # 4.10+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
| -rw-r--r-- | drivers/acpi/glue.c | 12 |
1 files changed, 6 insertions, 6 deletions
diff --git a/drivers/acpi/glue.c b/drivers/acpi/glue.c index fb19e1cdb641..edc8663b5db3 100644 --- a/drivers/acpi/glue.c +++ b/drivers/acpi/glue.c @@ -99,13 +99,13 @@ static int find_child_checks(struct acpi_device *adev, bool check_children) return -ENODEV; /* - * If the device has a _HID (or _CID) returning a valid ACPI/PNP - * device ID, it is better to make it look less attractive here, so that - * the other device with the same _ADR value (that may not have a valid - * device ID) can be matched going forward. [This means a second spec - * violation in a row, so whatever we do here is best effort anyway.] + * If the device has a _HID returning a valid ACPI/PNP device ID, it is + * better to make it look less attractive here, so that the other device + * with the same _ADR value (that may not have a valid device ID) can be + * matched going forward. [This means a second spec violation in a row, + * so whatever we do here is best effort anyway.] */ - return sta_present && list_empty(&adev->pnp.ids) ? + return sta_present && !adev->pnp.type.platform_id ? FIND_CHILD_MAX_SCORE : FIND_CHILD_MIN_SCORE; } |