| Message ID | 20190322154425.3852517-3-arnd@arndb.de |
|---|---|
| State | New |
| Headers | show |
| Series | candidates from spreadtrum 4.4 product kernel | expand |
On Tue, Mar 26, 2019 at 08:55:14AM +0100, Arnd Bergmann wrote: > On Tue, Mar 26, 2019 at 2:23 AM Greg KH <gregkh@linuxfoundation.org> wrote: > > > > On Fri, Mar 22, 2019 at 04:43:53PM +0100, Arnd Bergmann wrote: > > > From: Ravindra Lokhande <rlokhande@nvidia.com> > > > > > > Compress offload does not support ioctl calls from a 32bit userspace > > > in a 64 bit kernel. This patch adds support for ioctls from a 32bit > > > userspace in a 64bit kernel > > > > > > Signed-off-by: Ravindra Lokhande <rlokhande@nvidia.com> > > > Acked-by: Vinod Koul <vinod.koul@intel.com> > > > Signed-off-by: Takashi Iwai <tiwai@suse.de> > > > (cherry picked from commit c10368897e104c008c610915a218f0fe5fa4ec96) > > > Signed-off-by: Arnd Bergmann <arnd@arndb.de> > > > --- > > > sound/core/compress_offload.c | 13 +++++++++++++ > > > 1 file changed, 13 insertions(+) > > > > How is this not a "new feature"? What bug does this fix? Has this ever > > worked in the past? > > It has never worked in the past, but I consider it a bug for the compat layer > to behave differently from native code. In this case, any 32-bit application > using the SNDRV_COMPRESS_* ioctls will just fail to do anything on > a 64-bit kernel at all without the trivial fix that should have been there when > the driver was originally merged. Ok, fair enough, now queued up. greg k-h
diff --git a/sound/core/compress_offload.c b/sound/core/compress_offload.c index 6163bf3e8177..33d40d6fa3f1 100644 --- a/sound/core/compress_offload.c +++ b/sound/core/compress_offload.c @@ -38,6 +38,7 @@ #include <linux/uio.h> #include <linux/uaccess.h> #include <linux/module.h> +#include <linux/compat.h> #include <sound/core.h> #include <sound/initval.h> #include <sound/compress_params.h> @@ -858,6 +859,15 @@ static long snd_compr_ioctl(struct file *f, unsigned int cmd, unsigned long arg) return retval; } +/* support of 32bit userspace on 64bit platforms */ +#ifdef CONFIG_COMPAT +static long snd_compr_ioctl_compat(struct file *file, unsigned int cmd, + unsigned long arg) +{ + return snd_compr_ioctl(file, cmd, (unsigned long)compat_ptr(arg)); +} +#endif + static const struct file_operations snd_compr_file_ops = { .owner = THIS_MODULE, .open = snd_compr_open, @@ -865,6 +875,9 @@ static const struct file_operations snd_compr_file_ops = { .write = snd_compr_write, .read = snd_compr_read, .unlocked_ioctl = snd_compr_ioctl, +#ifdef CONFIG_COMPAT + .compat_ioctl = snd_compr_ioctl_compat, +#endif .mmap = snd_compr_mmap, .poll = snd_compr_poll, };