On Wed, 5 Jan 2022 at 10:41, Jiasheng Jiang <jiasheng@xxxxxxxxxxx> wrote: > > If there is no suitable resource, platform_get_resource() will return > NULL. > Therefore in order to avoid the dereference of the NULL pointer, it > should be better to check the 'res'. > > Fixes: 27cbd7e815a8 ("mmc: sh_mmcif: rework dma channel handling") I think this fixes tag is wrong. The problem seems to have been there way before this point. I suggest we instead just tag it for stable - and then let it be applied to whatever kernel version it can. Does it make sense to you? Kind regards Uffe > Signed-off-by: Jiasheng Jiang <jiasheng@xxxxxxxxxxx> > --- > drivers/mmc/host/sh_mmcif.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/drivers/mmc/host/sh_mmcif.c b/drivers/mmc/host/sh_mmcif.c > index e5e457037235..45dfa3b0be9c 100644 > --- a/drivers/mmc/host/sh_mmcif.c > +++ b/drivers/mmc/host/sh_mmcif.c > @@ -405,6 +405,9 @@ static int sh_mmcif_dma_slave_config(struct sh_mmcif_host *host, > struct dma_slave_config cfg = { 0, }; > > res = platform_get_resource(host->pd, IORESOURCE_MEM, 0); > + if (!res) > + return -EINVAL; > + > cfg.direction = direction; > > if (direction == DMA_DEV_TO_MEM) { > -- > 2.25.1 >