On Fri, Nov 26, 2021 at 05:57:58PM +0100, Christophe Leroy wrote: > > > Le 26/11/2021 à 17:54, Greg Kroah-Hartman a écrit : > > On Fri, Nov 26, 2021 at 05:47:58PM +0100, Christophe Leroy wrote: > > > sparse warnings: (new ones prefixed by >>) > > > > > drivers/w1/slaves/w1_ds28e04.c:342:13: sparse: sparse: incorrect type > > > > > in initializer (different address spaces) @@ expected char > > > > > [noderef] __user *_pu_addr @@ got char *buf @@ > > > drivers/w1/slaves/w1_ds28e04.c:342:13: sparse: expected char > > > [noderef] __user *_pu_addr > > > drivers/w1/slaves/w1_ds28e04.c:342:13: sparse: got char *buf > > > > > drivers/w1/slaves/w1_ds28e04.c:356:13: sparse: sparse: incorrect type > > > > > in initializer (different address spaces) @@ expected char const > > > > > [noderef] __user *_gu_addr @@ got char const *buf @@ > > > drivers/w1/slaves/w1_ds28e04.c:356:13: sparse: expected char > > > const [noderef] __user *_gu_addr > > > drivers/w1/slaves/w1_ds28e04.c:356:13: sparse: got char const *buf > > > > > > The buffer buf is a failsafe buffer in kernel space, it's not user > > > memory hence doesn't deserve the use of get_user() or put_user(). > > > > > > Access 'buf' content directly. > > > > > > Reported-by: kernel test robot <l...@intel.com> > > > Link: https://lore.kernel.org/lkml/202111190526.k5vb7nwc-...@intel.com/T/ > > > Signed-off-by: Christophe Leroy <christophe.le...@csgroup.eu> > > > --- > > > v2: Use sysfs_emit() and kstrtobool() > > > --- > > > drivers/w1/slaves/w1_ds28e04.c | 25 +++---------------------- > > > 1 file changed, 3 insertions(+), 22 deletions(-) > > > > > > diff --git a/drivers/w1/slaves/w1_ds28e04.c > > > b/drivers/w1/slaves/w1_ds28e04.c > > > index e4f336111edc..98f80f412cfd 100644 > > > --- a/drivers/w1/slaves/w1_ds28e04.c > > > +++ b/drivers/w1/slaves/w1_ds28e04.c > > > @@ -32,7 +32,7 @@ static int w1_strong_pullup = 1; > > > module_param_named(strong_pullup, w1_strong_pullup, int, 0); > > > /* enable/disable CRC checking on DS28E04-100 memory accesses */ > > > -static char w1_enable_crccheck = 1; > > > +static bool w1_enable_crccheck = true; > > > #define W1_EEPROM_SIZE 512 > > > #define W1_PAGE_COUNT 16 > > > @@ -339,32 +339,13 @@ static BIN_ATTR_RW(pio, 1); > > > static ssize_t crccheck_show(struct device *dev, struct > > > device_attribute *attr, > > > char *buf) > > > { > > > - if (put_user(w1_enable_crccheck + 0x30, buf)) > > > - return -EFAULT; > > > - > > > - return sizeof(w1_enable_crccheck); > > > + return sysfs_emit(buf, "%d\n", w1_enable_crccheck); > > > } > > > static ssize_t crccheck_store(struct device *dev, struct > > > device_attribute *attr, > > > const char *buf, size_t count) > > > { > > > - char val; > > > - > > > - if (count != 1 || !buf) > > > - return -EINVAL; > > > - > > > - if (get_user(val, buf)) > > > - return -EFAULT; > > > - > > > - /* convert to decimal */ > > > - val = val - 0x30; > > > - if (val != 0 && val != 1) > > > - return -EINVAL; > > > - > > > - /* set the new value */ > > > - w1_enable_crccheck = val; > > > - > > > - return sizeof(w1_enable_crccheck); > > > + return kstrtobool(buf, &w1_enable_crccheck) ? : count; > > > > Please spell this line out, using ? : is unreadable at times. > > > > You prefer something like: > > int err = kstrtobool(buf, &w1_enable_crccheck); > > return err ? err : count; > > > Or > > int err = kstrtobool(buf, &w1_enable_crccheck); > > if (err) > return err; > > return count;
This one. Write code for people to read first, compiler second. thanks, greg k-h
