ALSA: us122l: Fix pcm_usb_stream mmapping regression
authorTakashi Iwai <tiwai@suse.de>
Mon, 14 Oct 2013 14:02:15 +0000 (16:02 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Mon, 4 Nov 2013 12:31:06 +0000 (04:31 -0800)
commit1f931f65de9d04daf024eeb4dd6a8fe93b7a8e91
tree5459f52deba026588dd75f9ffb3280d264f50240
parent7ed008638ee15991b79d8867d382e141fee89a69
ALSA: us122l: Fix pcm_usb_stream mmapping regression

commit ac536a848a1643e4b87e8fbd376a63091afc2ccc upstream.

The pcm_usb_stream plugin requires the mremap explicitly for the read
buffer, as it expands itself once after reading the required size.
But the commit [314e51b9: mm: kill vma flag VM_RESERVED and
mm->reserved_vm counter] converted blindly to a combination of
VM_DONTEXPAND | VM_DONTDUMP like other normal drivers, and this
resulted in the failure of mremap().

For fixing this regression, we need to remove VM_DONTEXPAND for the
read-buffer mmap.

Reported-and-tested-by: James Miller <jamesstewartmiller@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sound/usb/usx2y/us122l.c