Messages in this thread | | | Subject | Re: [PATCH] ALSA: pcm: Remove VLA usage | From | Takashi Sakamoto <> | Date | Tue, 13 Mar 2018 22:59:10 +0900 |
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Hi,
On Mar 13 2018 20:37, Takashi Iwai wrote: > A helper function used by snd_pcm_hw_refine() still keeps using VLA > for timestamps of hw constraint rules that are non-fixed size. > > Let's replace the VLA with a simple kmalloc() array. > > Reference: https://lkml.org/lkml/2018/3/7/621 > Signed-off-by: Takashi Iwai <tiwai@suse.de> > --- > sound/core/pcm_native.c | 19 ++++++++++++------- > 1 file changed, 12 insertions(+), 7 deletions(-)
Yeah. I have concerned about it for a long time but kept it as is because it had no issue. Now, let's obsolete it.
Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
> diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c > index 77ba50ddcf9e..756a9a3884a5 100644 > --- a/sound/core/pcm_native.c > +++ b/sound/core/pcm_native.c > @@ -323,7 +323,7 @@ static int constrain_params_by_rules(struct snd_pcm_substream *substream, > struct snd_pcm_hw_constraints *constrs = > &substream->runtime->hw_constraints; > unsigned int k; > - unsigned int rstamps[constrs->rules_num]; > + unsigned int *rstamps; > unsigned int vstamps[SNDRV_PCM_HW_PARAM_LAST_INTERVAL + 1]; > unsigned int stamp; > struct snd_pcm_hw_rule *r; > @@ -331,7 +331,7 @@ static int constrain_params_by_rules(struct snd_pcm_substream *substream, > struct snd_mask old_mask; > struct snd_interval old_interval; > bool again; > - int changed; > + int changed, err = 0; > > /* > * Each application of rule has own sequence number. > @@ -339,8 +339,9 @@ static int constrain_params_by_rules(struct snd_pcm_substream *substream, > * Each member of 'rstamps' array represents the sequence number of > * recent application of corresponding rule. > */ > - for (k = 0; k < constrs->rules_num; k++) > - rstamps[k] = 0; > + rstamps = kcalloc(constrs->rules_num, sizeof(unsigned int), GFP_KERNEL); > + if (!rstamps) > + return -ENOMEM; > > /* > * Each member of 'vstamps' array represents the sequence number of > @@ -398,8 +399,10 @@ static int constrain_params_by_rules(struct snd_pcm_substream *substream, > } > > changed = r->func(params, r); > - if (changed < 0) > - return changed; > + if (changed < 0) { > + err = changed; > + goto out; > + } > > /* > * When the parameter is changed, notify it to the caller > @@ -430,7 +433,9 @@ static int constrain_params_by_rules(struct snd_pcm_substream *substream, > if (again) > goto retry; > > - return 0; > + out: > + kfree(rstamps); > + return err; > } > > static int fixup_unreferenced_params(struct snd_pcm_substream *substream,
Thanks
Takashi Sakamoto
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