Re: [PATCH] mtd: stm32-quadspi: replace "%p" with "%pK"

From: Boris Brezillon
Date: Fri Jul 06 2018 - 10:47:55 EST


On Fri, 06 Jul 2018 16:44:44 +0200
Richard Weinberger <richard@xxxxxx> wrote:

> Am Freitag, 6. Juli 2018, 15:05:25 CEST schrieb Benjamin Gaignard:
> > The format specifier "%p" can leak kernel addresses.
> > Use "%pK" instead.
>
> Does %pK really make sense for dev_dbg()?
> When the driver is being debugged "leaking" is on purpose. :)

%p already gives you a hash of the pointer address. At least with %pK
you can turn it off through a sysctl :).

>
> Thanks,
> //richard
>
> > Signed-off-by: Benjamin Gaignard <benjamin.gaignard@xxxxxx>
> > ---
> > drivers/mtd/spi-nor/stm32-quadspi.c | 6 +++---
> > 1 file changed, 3 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/mtd/spi-nor/stm32-quadspi.c b/drivers/mtd/spi-nor/stm32-quadspi.c
> > index 72553506a00b..13e9fc961d3b 100644
> > --- a/drivers/mtd/spi-nor/stm32-quadspi.c
> > +++ b/drivers/mtd/spi-nor/stm32-quadspi.c
> > @@ -355,7 +355,7 @@ static int stm32_qspi_read_reg(struct spi_nor *nor,
> > struct device *dev = flash->qspi->dev;
> > struct stm32_qspi_cmd cmd;
> >
> > - dev_dbg(dev, "read_reg: cmd:%#.2x buf:%p len:%#x\n", opcode, buf, len);
> > + dev_dbg(dev, "read_reg: cmd:%#.2x buf:%pK len:%#x\n", opcode, buf, len);
> >
> > memset(&cmd, 0, sizeof(cmd));
> > cmd.opcode = opcode;
> > @@ -376,7 +376,7 @@ static int stm32_qspi_write_reg(struct spi_nor *nor, u8 opcode,
> > struct device *dev = flash->qspi->dev;
> > struct stm32_qspi_cmd cmd;
> >
> > - dev_dbg(dev, "write_reg: cmd:%#.2x buf:%p len:%#x\n", opcode, buf, len);
> > + dev_dbg(dev, "write_reg: cmd:%#.2x buf:%pK len:%#x\n", opcode, buf, len);
> >
> > memset(&cmd, 0, sizeof(cmd));
> > cmd.opcode = opcode;
> > @@ -398,7 +398,7 @@ static ssize_t stm32_qspi_read(struct spi_nor *nor, loff_t from, size_t len,
> > struct stm32_qspi_cmd cmd;
> > int err;
> >
> > - dev_dbg(qspi->dev, "read(%#.2x): buf:%p from:%#.8x len:%#zx\n",
> > + dev_dbg(qspi->dev, "read(%#.2x): buf:%pK from:%#.8x len:%#zx\n",
> > nor->read_opcode, buf, (u32)from, len);
> >
> > memset(&cmd, 0, sizeof(cmd));
> >
>
>