Re: [PATCH] mmc: sdhci-sprd: Fix some resource leaks in the remove function

[Christophe JAILLET]

Le 17/12/2020 à 23:55, Orson Zhai a écrit :
> + cc: Billows
>
> Hi Christophe,
> On Fri, Dec 18, 2020 at 4:50 AM Christophe JAILLET
> <christophe.jaillet@xxxxxxxxxx> wrote:
> > 'sdhci_remove_host()' and 'sdhci_pltfm_free()' should be used in place of
> > 'mmc_remove_host()' and 'mmc_free_host()'.
> >
> > This avoids some resource leaks, is more in line with the error handling
> > path of the probe function, and is more consistent with other drivers.
> >
> > Fixes: fb8bd90f83c4 ("mmc: sdhci-sprd: Add Spreadtrum's initial host controller")
> > Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
> > ---
> > Other adjustment may be needed.
> > I'm not sure at all of the 0 passed to 'sdhci_remove_host()'. Some drivers
> > pass 0, some have some more complicated computation.
> > ---
> >   drivers/mmc/host/sdhci-sprd.c | 6 +++---
> >   1 file changed, 3 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/mmc/host/sdhci-sprd.c b/drivers/mmc/host/sdhci-sprd.c
> > index f85171edabeb..5dc36efff47f 100644
> > --- a/drivers/mmc/host/sdhci-sprd.c
> > +++ b/drivers/mmc/host/sdhci-sprd.c
> > @@ -708,14 +708,14 @@ static int sdhci_sprd_remove(struct platform_device *pdev)
> >   {
> >          struct sdhci_host *host = platform_get_drvdata(pdev);
> >          struct sdhci_sprd_host *sprd_host = TO_SPRD_HOST(host);
> > -       struct mmc_host *mmc = host->mmc;
> >
> > -       mmc_remove_host(mmc);
> > +       sdhci_remove_host(host, 0);
> > +
> >          clk_disable_unprepare(sprd_host->clk_sdio);
> >          clk_disable_unprepare(sprd_host->clk_enable);
> >          clk_disable_unprepare(sprd_host->clk_2x_enable);
> >
> > -       mmc_free_host(mmc);
> > +       sdhci_pltfm_free(pdev);
>
> I saw a lot of drivers also use mmc_free_host().
> Do you have patches elsewhere to clean them?

As far as I can see, all drivers that use 'mmc_free_host' also use 
'mmc_alloc_host'. (based on 5.10.1 and unless error)

The only exception is 'sdhci-sprd.c'.

So no, I don't plan any other clean-up.



To spot it, I run one of my own cocci script which compare functions 
called in the remove function and in the error handling path of the probe.

So I caught this one because 'mmc_free_host' is used in the porbe and 
'sdhci_pltfm_free' in the remove function.


CJ

> Thanks,
> -Orson
>
> >          return 0;
> >   }
> > --
> > 2.27.0