From: Mika Westerberg Date: Mon, 2 Sep 2013 10:30:25 +0000 (+0300) Subject: ACPI / LPSS: don't crash if a device has no MMIO resources X-Git-Tag: firefly_0821_release~176^2~5323^2~4^2 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=af65cfe9aeae03e0682bebdf4db94582d75562dd;p=firefly-linux-kernel-4.4.55.git ACPI / LPSS: don't crash if a device has no MMIO resources Intel LPSS devices that are enumerated from ACPI have both MMIO and IRQ resources returned in their _CRS method. However, Apple Macbook Air with Haswell has LPSS devices enumerated from PCI bus instead and _CRS method returns only an interrupt number (but the device has _HID set that causes the scan handler to match it). The current ACPI / LPSS code sets pdata->dev_desc only when MMIO resource is found for the device and in case of Macbook Air it is never found. That leads to a NULL pointer dereference in register_device_clock(). Correct this by always setting the pdata->dev_desc. Reported-and-tested-by: Imre Kaloz Signed-off-by: Mika Westerberg Cc: 3.10+ # 3.10+ Signed-off-by: Rafael J. Wysocki --- diff --git a/drivers/acpi/acpi_lpss.c b/drivers/acpi/acpi_lpss.c index 6a382188fa20..fb78bb9ad8f6 100644 --- a/drivers/acpi/acpi_lpss.c +++ b/drivers/acpi/acpi_lpss.c @@ -257,12 +257,13 @@ static int acpi_lpss_create_device(struct acpi_device *adev, pdata->mmio_size = resource_size(&rentry->res); pdata->mmio_base = ioremap(rentry->res.start, pdata->mmio_size); - pdata->dev_desc = dev_desc; break; } acpi_dev_free_resource_list(&resource_list); + pdata->dev_desc = dev_desc; + if (dev_desc->clk_required) { ret = register_device_clock(adev, pdata); if (ret) {