Re: [PATCH v2 4/7] remoteproc: Use kstrdup_const() rather than kstrup()

[Suman Anna]

On 4/15/20 4:25 PM, Alex Elder wrote:
> On 4/15/20 3:48 PM, Mathieu Poirier wrote:
> > For cases where @firmware is declared "const char *", use function
> > kstrdup_const() to avoid needlessly creating another copy on the
> > heap.
> >
> > Suggested-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
> > Signed-off-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
>
> Looks good.
>
> Reviewed-by: Alex Elder <elder@xxxxxxxxxx>
>
> > ---
> >   drivers/remoteproc/remoteproc_core.c | 4 ++--
> >   include/linux/remoteproc.h           | 2 +-
> >   2 files changed, 3 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
> > index 9899467fa1cf..ebaff496ef81 100644
> > --- a/drivers/remoteproc/remoteproc_core.c
> > +++ b/drivers/remoteproc/remoteproc_core.c
> > @@ -1982,7 +1982,7 @@ static const struct device_type rproc_type = {
> >   static int rproc_alloc_firmware(struct rproc *rproc,
> >   				const char *name, const char *firmware)
> >   {
> > -	char *p;
> > +	const char *p;
> >   
> >   	if (!firmware)
> >   		/*
> > @@ -1991,7 +1991,7 @@ static int rproc_alloc_firmware(struct rproc *rproc,
> >   		 */
> >   		p = kasprintf(GFP_KERNEL, "rproc-%s-fw", name);

So, to be consistent for both paths, should we be using 
kvasprintf_const() here and kfree_const() in release. The kfree_const() 
is needed to account for the kstrdup_const below for sure.

regards
Suman

> >   	else
> > -		p = kstrdup(firmware, GFP_KERNEL);
> > +		p = kstrdup_const(firmware, GFP_KERNEL);
> >   
> >   	if (!p)
> >   		return -ENOMEM;
> > diff --git a/include/linux/remoteproc.h b/include/linux/remoteproc.h
> > index 9c07d7958c53..38607107b7cb 100644
> > --- a/include/linux/remoteproc.h
> > +++ b/include/linux/remoteproc.h
> > @@ -489,7 +489,7 @@ struct rproc {
> >   	struct list_head node;
> >   	struct iommu_domain *domain;
> >   	const char *name;
> > -	char *firmware;
> > +	const char *firmware;
> >   	void *priv;
> >   	struct rproc_ops *ops;
> >   	struct device dev;