• Takashi Iwai's avatar
    ALSA: usx2y: Suppress kernel warning at page allocation failures · 7682e399
    Takashi Iwai authored
    The usx2y driver allocates the stream read/write buffers in continuous
    pages depending on the stream setup, and this may spew the kernel
    warning messages with a stack trace like:
      WARNING: CPU: 1 PID: 1846 at mm/page_alloc.c:3883
      __alloc_pages_slowpath+0x1ef2/0x2d70
      Modules linked in:
      CPU: 1 PID: 1846 Comm: kworker/1:2 Not tainted
      ....
    
    It may confuse user as if it were any serious error, although this is
    no fatal error and the driver handles the error case gracefully.
    Since the driver has already some sanity check of the given size (128
    and 256 pages), it can't pass any crazy value.  So it's merely page
    fragmentation.
    
    This patch adds __GFP_NOWARN to each caller for suppressing such
    kernel warnings.  The original issue was spotted by syzkaller.
    Reported-by: default avatarAndrey Konovalov <andreyknvl@google.com>
    Tested-by: default avatarAndrey Konovalov <andreyknvl@google.com>
    Cc: <stable@vger.kernel.org>
    Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
    7682e399
usb_stream.c 19.1 KB