Commit 7682e399 authored by Takashi Iwai's avatar Takashi Iwai

ALSA: usx2y: Suppress kernel warning at page allocation failures

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
  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

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 <>
Tested-by: default avatarAndrey Konovalov <>
Cc: <>
Signed-off-by: default avatarTakashi Iwai <>
parent 51db452d
......@@ -191,7 +191,8 @@ struct usb_stream *usb_stream_new(struct usb_stream_kernel *sk,
pg = get_order(read_size);
sk->s = (void *) __get_free_pages(GFP_KERNEL|__GFP_COMP|__GFP_ZERO, pg);
sk->s = (void *) __get_free_pages(GFP_KERNEL|__GFP_COMP|__GFP_ZERO|
__GFP_NOWARN, pg);
if (!sk->s) {
snd_printk(KERN_WARNING "couldn't __get_free_pages()\n");
goto out;
......@@ -211,7 +212,8 @@ struct usb_stream *usb_stream_new(struct usb_stream_kernel *sk,
pg = get_order(write_size);
sk->write_page =
(void *)__get_free_pages(GFP_KERNEL|__GFP_COMP|__GFP_ZERO, pg);
(void *)__get_free_pages(GFP_KERNEL|__GFP_COMP|__GFP_ZERO|
__GFP_NOWARN, pg);
if (!sk->write_page) {
snd_printk(KERN_WARNING "couldn't __get_free_pages()\n");
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