From ac536a848a1643e4b87e8fbd376a63091afc2ccc Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Mon, 14 Oct 2013 16:02:15 +0200 Subject: [PATCH] ALSA: us122l: Fix pcm_usb_stream mmapping regression 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 Cc: Signed-off-by: Takashi Iwai --- sound/usb/usx2y/us122l.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/sound/usb/usx2y/us122l.c b/sound/usb/usx2y/us122l.c index d0323a693ba2..999550bbad40 100644 --- a/sound/usb/usx2y/us122l.c +++ b/sound/usb/usx2y/us122l.c @@ -262,7 +262,9 @@ static int usb_stream_hwdep_mmap(struct snd_hwdep *hw, } area->vm_ops = &usb_stream_hwdep_vm_ops; - area->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP; + area->vm_flags |= VM_DONTDUMP; + if (!read) + area->vm_flags |= VM_DONTEXPAND; area->vm_private_data = us122l; atomic_inc(&us122l->mmap_count); out: