[alsa-devel] [PATCH] ASoC: topology: fix soc_tplg_fe_link_create() - link->dobj initialization order

[Greg Kroah-Hartman]

On Wed, Jan 22, 2020 at 08:25:30PM +0000, Mark Brown wrote:
> On Wed, Jan 22, 2020 at 01:28:57PM -0600, Pierre-Louis Bossart wrote:
> > On 1/22/20 1:07 PM, Jaroslav Kysela wrote:
> 
> > > The code which checks the return value for snd_soc_add_dai_link() call
> > > in soc_tplg_fe_link_create() moved the snd_soc_add_dai_link() call before
> > > link->dobj members initialization.
> 
> > > While it does not affect the latest kernels, the old soc-core.c code
> > > in the stable kernels is affected. The snd_soc_add_dai_link() function uses
> > > the link->dobj.type member to check, if the link structure is valid.
> 
> > > Reorder the link->dobj initialization to make things work again.
> > > It's harmless for the recent code (and the structure should be properly
> > > initialized before other calls anyway).
> 
> > > The problem is in stable linux-5.4.y since version 5.4.11 when the
> > > upstream commit 76d270364932 was applied.
> 
> > I am not following. Is this a fix for linux-5.4-y only, or is it needed on
> > Mark's tree? In the latter case, what is broken? We've been using Mark's
> > tree without issues, wondering what we missed?
> 
> He's saying it's a fix for stable but it's just a cleanup and robustness
> improvement in current kernels - when the patch 76d270364932 (ASoC:
> topology: Check return value for snd_soc_add_dai_link()) was backported
> by the bot the bot missed some other context which triggered bugs.
> 
> Copying in Sasha and Greg for stable (not sure if the list works by
> itself).

How this was marked-up is fine, our scripts can easily handle it,
thanks.

greg k-h