Re: linux-next: build failure after merge of the akpm tree

From: Andrew Morton
Date: Fri Jan 15 2016 - 18:14:19 EST


On Sat, 16 Jan 2016 10:00:47 +1100 Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx> wrote:

> Hi Andrew,
> > +#define SNDRV_COMPRESS_GET_CODEC_CAPS _IOWR('C', 0x11, struct snd_compr_caps)
> > #define SNDRV_COMPRESS_SET_PARAMS _IOW('C', 0x12, struct snd_compr_params)
> > #define SNDRV_COMPRESS_GET_PARAMS _IOR('C', 0x13, struct snd_codec)
> > #define SNDRV_COMPRESS_SET_METADATA _IOW('C', 0x14,\
> >
> > then it compiles OK. So there's something special about `struct
> > snd_compr_codec_caps' which is confusing the compiler.
>
> Its very big (hint, I think it is bigger than 1 << 13).

ah-hah.

sizeof(struct snd_compr_codec_caps) is 11144 on x86_64
allyesconfig, but x86_64 uses (1<<14), not (1<<13) - x86_64 has more
space in the ioctl payload.


So. Sound guys: your struct snd_compr_codec_caps is too large for
powerpc ioctls.