On Mon, 14 Mar 2016 11:13:58 +0100, Mauro Carvalho Chehab wrote: > > Em Mon, 14 Mar 2016 09:22:37 +0200 > Sakari Ailus <sakari.ailus@xxxxxx> escreveu: > > > Hi Shuah, > > > > On Sat, Mar 12, 2016 at 06:48:09PM -0700, Shuah Khan wrote: > > > Add GFP flags to media_create_pad_link(), media_create_intf_link(), > > > media_devnode_create(), and media_add_link() that could get called > > > in atomic context to allow callers to pass in the right flags for > > > memory allocation. > > > > > > tree-wide driver changes for media_*() GFP flags change: > > > Change drivers to add gfpflags to interffaces, media_create_pad_link(), > > > media_create_intf_link() and media_devnode_create(). > > > > > > Signed-off-by: Shuah Khan <shuahkh@xxxxxxxxxxxxxxx> > > > Suggested-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxx> > > > > What's the use case for calling the above functions in an atomic context? > > > > ALSA code seems to do a lot of stuff at atomic context. That's what > happens on my test machine when au0828 gets probed before > snd-usb-audio: > http://pastebin.com/LEX5LD5K > > It seems that ALSA USB probe routine (usb_audio_probe) happens in > atomic context. No, usb_audio_probe() doesn't take a lock. But media_device_register_entity() seems taking a spinlock, instead. Takashi
