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authorRadim Krčmář <rkrcmar@redhat.com>2015-05-29 22:18:52 +0200
committerDarren Hart <dvhart@linux.intel.com>2015-06-07 21:30:12 -0700
commit55cd3f01d631b0a3a022393bac234b9a643301f6 (patch)
treeb000837fad35463adf406b6663dfe2b85ac9aa71 /drivers/platform
parent4fa9dabcffc8e16601307d3d56b58c68d9716ba4 (diff)
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pvpanic: handle missing _STA correctly
pvpanic was not properly detected when _STA was missing. ACPI 6.0 April 2015, 6.3.7 _STA (Status) If a device object (including the processor object) does not have an _STA object, then OSPM assumes that all of the above bits are set (i.e., the device is present, enabled, shown in the UI, and functioning). Not adhering to the specification made pvpanic dormant under QEMU 2.3. The original patch used acpi_bus_get_status_handle, which was not being exported, so module build blew up; switch to acpi_bus_get_status and use the status it populates. Populated status is a bitfield so we can make the code self-documenting. We do not check 'present' because 'enabled' has to be false in that case by specification. Older QEMUs set 0xff to status and newer ones do 0xb. Suggested-by: Igor Mammedov <imammedo@redhat.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Reviewed-by: Igor Mammedov <imammedo@redhat.com> [dvhart@linux.intel.com: Merge acpi_bug_get_status fix to avoid bisect breakage] Signed-off-by: Darren Hart <dvhart@linux.intel.com>
Diffstat (limited to 'drivers/platform')
-rw-r--r--drivers/platform/x86/pvpanic.c10
1 files changed, 5 insertions, 5 deletions
diff --git a/drivers/platform/x86/pvpanic.c b/drivers/platform/x86/pvpanic.c
index 073a90a63dbc..fd86daba7ffd 100644
--- a/drivers/platform/x86/pvpanic.c
+++ b/drivers/platform/x86/pvpanic.c
@@ -92,13 +92,13 @@ pvpanic_walk_resources(struct acpi_resource *res, void *context)
static int pvpanic_add(struct acpi_device *device)
{
- acpi_status status;
- u64 ret;
+ int ret;
- status = acpi_evaluate_integer(device->handle, "_STA", NULL,
- &ret);
+ ret = acpi_bus_get_status(device);
+ if (ret < 0)
+ return ret;
- if (ACPI_FAILURE(status) || (ret & 0x0B) != 0x0B)
+ if (!device->status.enabled || !device->status.functional)
return -ENODEV;
acpi_walk_resources(device->handle, METHOD_NAME__CRS,