Re: [PATCH] media: add GFP flag to media_*() that could get called in atomic context

[Mauro Carvalho Chehab]

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.

Regards,
Mauro