Hi Julia, On Wed, 8 Sep 2010 11:48:17 +0200 (CEST), Julia Lawall wrote: > OK, thanks. I will look at the code again. Any update on this patch? > On Wed, 8 Sep 2010, Jean Delvare wrote: > > > Hi Julia, > > > > On Wed, 8 Sep 2010 07:58:45 +0200 (CEST), Julia Lawall wrote: > > > From: Julia Lawall <julia@xxxxxxx> > > > > > > In each case, the function has an unsigned return type, but returns a > > > negative constant to indicate an error condition. The result of calling > > > the function is always stored in a variable of type (signed) int, and thus > > > unsigned can be dropped from the return type. > > > > > > A sematic match that finds this problem is as follows: > > > (http://coccinelle.lip6.fr/) > > > > > > // <smpl> > > > @exists@ > > > identifier f; > > > constant C; > > > @@ > > > > > > unsigned f(...) > > > { <+... > > > * return -C; > > > ...+> } > > > // </smpl> > > > > > > Signed-off-by: Julia Lawall <julia@xxxxxxx> > > > > > > --- > > > drivers/i2c/busses/i2c-amd8111.c | 4 ++-- > > > 1 file changed, 2 insertions(+), 2 deletions(-) > > > > > > diff --git a/drivers/i2c/busses/i2c-amd8111.c b/drivers/i2c/busses/i2c-amd8111.c > > > index af1e5e2..02a3726 100644 > > > --- a/drivers/i2c/busses/i2c-amd8111.c > > > +++ b/drivers/i2c/busses/i2c-amd8111.c > > > @@ -69,7 +69,7 @@ static struct pci_driver amd8111_driver; > > > * ACPI 2.0 chapter 13 access of registers of the EC > > > */ > > > > > > -static unsigned int amd_ec_wait_write(struct amd_smbus *smbus) > > > +static int amd_ec_wait_write(struct amd_smbus *smbus) > > > { > > > int timeout = 500; > > > > > > @@ -85,7 +85,7 @@ static unsigned int amd_ec_wait_write(struct amd_smbus *smbus) > > > return 0; > > > } > > > > > > -static unsigned int amd_ec_wait_read(struct amd_smbus *smbus) > > > +static int amd_ec_wait_read(struct amd_smbus *smbus) > > > { > > > int timeout = 500; > > > > > > > > > > Thanks for reporting. Unfortunately the fix above is incomplete. > > amd_ec_wait_write() and amd_ec_wait_read() are called by amd_ec_read() > > and amd_ec_write(), which will now attempt to return negative error > > codes as unsigned ints. So amd_ec_read() and amd_ec_write() must have > > their return type fixed too. > > > > Note that the driver code never checks for errors returned by > > amd_ec_read() or amd_ec_write() anyway, so the fix alone is a no-op. A > > real fix would have to also update the caller sites to properly deal > > with errors if then happen. > > > > -- > > Jean Delvare > > -- > > To unsubscribe from this list: send the line "unsubscribe kernel-janitors" in > > the body of a message to majordomo@xxxxxxxxxxxxxxx > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-i2c" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Jean Delvare -- To unsubscribe from this list: send the line "unsubscribe kernel-janitors" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
