I got the following kernel warning when loading snd-soc-skl module on Dell Latitude 7270 laptop: memremap attempted on mixed range 0x0000000000000000 size: 0x0 WARNING: CPU: 0 PID: 484 at kernel/memremap.c:98 memremap+0x8a/0x180 Call Trace: skl_nhlt_init+0x82/0xf0 [snd_soc_skl] skl_probe+0x2ee/0x7c0 [snd_soc_skl] ....
It seems that the machine doesn't support the SKL DSP gives the empty NHLT entry, and it triggers the warning. For avoiding it, let do the zero check before calling memremap().
Cc: stable@vger.kernel.org Signed-off-by: Takashi Iwai tiwai@suse.de --- sound/soc/intel/skylake/skl-nhlt.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/sound/soc/intel/skylake/skl-nhlt.c b/sound/soc/intel/skylake/skl-nhlt.c index ba265119e0a1..9dd77383a4a7 100644 --- a/sound/soc/intel/skylake/skl-nhlt.c +++ b/sound/soc/intel/skylake/skl-nhlt.c @@ -44,7 +44,8 @@ struct nhlt_acpi_table *skl_nhlt_init(struct device *dev) obj = acpi_evaluate_dsm(handle, &osc_guid, 1, 1, NULL); if (obj && obj->type == ACPI_TYPE_BUFFER) { nhlt_ptr = (struct nhlt_resource_desc *)obj->buffer.pointer; - nhlt_table = (struct nhlt_acpi_table *) + if (nhlt_ptr->length) + nhlt_table = (struct nhlt_acpi_table *) memremap(nhlt_ptr->min_addr, nhlt_ptr->length, MEMREMAP_WB); ACPI_FREE(obj);