ALSA: pcm: Fix refcount_inc() on zero usage
The recent rewrite of PCM link lock management introduced the refcount in snd_pcm_group object, managed by the kernel refcount_t API. This caused unexpected kernel warnings when the kernel is built with CONFIG_REFCOUNT_FULL=y. As the warning line indicates, the problem is obviously that we start with refcount=0 and do refcount_inc() for adding each PCM link, while refcount_t API doesn't like refcount_inc() performed on zero. For adapting the proper refcount_t usage, this patch changes the logic slightly: - The initial refcount is 1, assuming the single list entry - The refcount is incremented / decremented at each PCM link addition and deletion - ... which allows us concentrating only on the refcount as a release condition Fixes: f57f3df0 ("ALSA: pcm: More fine-grained PCM link locking") BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=204221 Reported-and-tested-by:Duncan Overbruck <kernel@duncano.de> Cc: <stable@vger.kernel.org> Signed-off-by:
Takashi Iwai <tiwai@suse.de>
parent
70256b42
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