4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Arnd Bergmann <arnd@xxxxxxxx> commit 13f99ebdd602ebdafb909e15ec6ffb1e34690167 upstream. The latest gcc-7.0.1 snapshot points out that we if nr_ch is zero, we never initialize some variables: sound/pci/au88x0/au88x0_core.c: In function 'vortex_adb_allocroute': sound/pci/au88x0/au88x0_core.c:2304:68: error: 'mix[0]' may be used uninitialized in this function [-Werror=maybe-uninitialized] sound/pci/au88x0/au88x0_core.c:2305:58: error: 'src[0]' may be used uninitialized in this function [-Werror=maybe-uninitialized] I assume this can never happen in practice, but adding a check here doesn't hurt either and avoids the warning. The code has been unchanged since the start of git history. Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx> Signed-off-by: Takashi Iwai <tiwai@xxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- sound/pci/au88x0/au88x0_core.c | 3 +++ 1 file changed, 3 insertions(+) --- a/sound/pci/au88x0/au88x0_core.c +++ b/sound/pci/au88x0/au88x0_core.c @@ -2279,6 +2279,9 @@ vortex_adb_allocroute(vortex_t *vortex, } else { int src[2], mix[2]; + if (nr_ch < 1) + return -EINVAL; + /* Get SRC and MIXER hardware resources. */ for (i = 0; i < nr_ch; i++) { if ((mix[i] =