From: Cezary Rojewski cezary.rojewski@intel.com

commit 9e6c382f5a6161eb55115fb56614b9827f2e7da3 upstream.

Some configurations expose no NHLT table at all within their /sys/firmware/acpi/tables. To prevent NULL-dereference errors from occurring, adjust probe flow and append additional safety checks in functions involved in NHLT lifecycle.

Signed-off-by: Cezary Rojewski cezary.rojewski@intel.com Reviewed-by: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com Link: https://lore.kernel.org/r/20200305145314.32579-5-cezary.rojewski@intel.com Signed-off-by: Mark Brown broonie@kernel.org Cc: stable@vger.kernel.org # 5.4.x Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- sound/soc/intel/skylake/skl-nhlt.c | 3 ++- sound/soc/intel/skylake/skl.c | 9 +++++++-- 2 files changed, 9 insertions(+), 3 deletions(-)

--- a/sound/soc/intel/skylake/skl-nhlt.c +++ b/sound/soc/intel/skylake/skl-nhlt.c @@ -182,7 +182,8 @@ void skl_nhlt_remove_sysfs(struct skl_de { struct device *dev = &skl->pci->dev;

- sysfs_remove_file(&dev->kobj, &dev_attr_platform_id.attr); + if (skl->nhlt) + sysfs_remove_file(&dev->kobj, &dev_attr_platform_id.attr); }

/* --- a/sound/soc/intel/skylake/skl.c +++ b/sound/soc/intel/skylake/skl.c @@ -632,6 +632,9 @@ static int skl_clock_device_register(str struct platform_device_info pdevinfo = {NULL}; struct skl_clk_pdata *clk_pdata;

+ if (!skl->nhlt) + return 0; + clk_pdata = devm_kzalloc(&skl->pci->dev, sizeof(*clk_pdata), GFP_KERNEL); if (!clk_pdata) @@ -1090,7 +1093,8 @@ out_dsp_free: out_clk_free: skl_clock_device_unregister(skl); out_nhlt_free: - intel_nhlt_free(skl->nhlt); + if (skl->nhlt) + intel_nhlt_free(skl->nhlt); out_free: skl_free(bus);

@@ -1139,7 +1143,8 @@ static void skl_remove(struct pci_dev *p skl_dmic_device_unregister(skl); skl_clock_device_unregister(skl); skl_nhlt_remove_sysfs(skl); - intel_nhlt_free(skl->nhlt); + if (skl->nhlt) + intel_nhlt_free(skl->nhlt); skl_free(bus); dev_set_drvdata(&pci->dev, NULL); }