On Sunday, July 31, 2016 4:48:44 PM CEST Arvind Yadav wrote: > IS_ERR_VALUE() assumes that parameter is an unsigned long. > It can not be used to check if 'unsigned int' is passed insted. > Which tends to reflect an error. > > In 64bit architectures sizeof (int) == 4 && sizeof (long) == 8. > IS_ERR_VALUE(x) is ((x) >= (unsigned long)-4095). > > IS_ERR_VALUE() of 'unsigned int' is always false because the 32bit > value is zero extended to 64 bits. > > Value of (unsigned int)-4095 is always less than value of > (unsigned long)-4095. > > Now We are taking only first 32 bit for error checking rest of the 32 bit > we ignore such that we get appropriate comparison on 64bit system as well. This is completely wrong: if you have a valid 64-bit pointer like 0x00001234ffffff00, this will be interpreted as an error now. > First 32bit of Value of (unsigned int)-4095 and (unsigned long)-4095 will > be equal. > > Signed-off-by: Arvind Yadav <arvind.yadav.cs@xxxxxxxxx> > --- > include/linux/err.h | 12 +++++++++++- > 1 file changed, 11 insertions(+), 1 deletion(-) > > diff --git a/include/linux/err.h b/include/linux/err.h > index 1e35588..c2a2789 100644 > --- a/include/linux/err.h > +++ b/include/linux/err.h > @@ -18,7 +18,17 @@ > > #ifndef __ASSEMBLY__ > > -#define IS_ERR_VALUE(x) unlikely((unsigned long)(void *)(x) >= (unsigned long)-MAX_ERRNO) > +#define IS_ERR_VALUE(x) unlikely(is_error_check(x)) > + > +static inline int is_error_check(unsigned long error) Please leave the existing macro alone. I think you were looking for something specific to the return code of qe_muram_alloc() function, so please add a helper in that subsystem if you need it, not in the generic header files. Arnd -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
