| Message ID | 1507488258-22409-1-git-send-email-chris.gekas@gmail.com (mailing list archive) |
|---|---|
| State | Rejected |
| Headers | show |
On Sun, Oct 08, 2017 at 07:44:18PM +0100, Christos Gkekas wrote: > Variable byte_offset is unsigned so checking whether it is greater or > equal to zero is redundant. > > Signed-off-by: Christos Gkekas <chris.gekas@gmail.com> Yep - looks sensible to me. Signed-off-by: Nick Dyer <nick@shmanahar.org> > --- > drivers/input/touchscreen/atmel_mxt_ts.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c > index 7659bc4..baafaed 100644 > --- a/drivers/input/touchscreen/atmel_mxt_ts.c > +++ b/drivers/input/touchscreen/atmel_mxt_ts.c > @@ -1356,7 +1356,7 @@ static int mxt_prepare_cfg_mem(struct mxt_data *data, > > byte_offset = reg + i - cfg_start_ofs; > > - if (byte_offset >= 0 && byte_offset < config_mem_size) { > + if (byte_offset < config_mem_size) { > *(config_mem + byte_offset) = val; > } else { > dev_err(dev, "Bad object: reg:%d, T%d, ofs=%d\n", > -- > 2.7.4 > -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Sun, Oct 08, 2017 at 08:41:16PM +0100, Nick Dyer wrote: > On Sun, Oct 08, 2017 at 07:44:18PM +0100, Christos Gkekas wrote: > > Variable byte_offset is unsigned so checking whether it is greater or > > equal to zero is redundant. > > > > Signed-off-by: Christos Gkekas <chris.gekas@gmail.com> > > Yep - looks sensible to me. > > Signed-off-by: Nick Dyer <nick@shmanahar.org> I believe this has been discussed before and Linus told us to keep the such checks as is: they neatly document the ranges of values, safe in case we ever change the type of the variables, and do not cost us anything at execution time. > > > --- > > drivers/input/touchscreen/atmel_mxt_ts.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c > > index 7659bc4..baafaed 100644 > > --- a/drivers/input/touchscreen/atmel_mxt_ts.c > > +++ b/drivers/input/touchscreen/atmel_mxt_ts.c > > @@ -1356,7 +1356,7 @@ static int mxt_prepare_cfg_mem(struct mxt_data *data, > > > > byte_offset = reg + i - cfg_start_ofs; > > > > - if (byte_offset >= 0 && byte_offset < config_mem_size) { > > + if (byte_offset < config_mem_size) { > > *(config_mem + byte_offset) = val; > > } else { > > dev_err(dev, "Bad object: reg:%d, T%d, ofs=%d\n", > > -- > > 2.7.4 > > Thanks.
On 09/10/17 10:38:55 -0700, Dmitry Torokhov wrote: > On Sun, Oct 08, 2017 at 08:41:16PM +0100, Nick Dyer wrote: > > On Sun, Oct 08, 2017 at 07:44:18PM +0100, Christos Gkekas wrote: > > > Variable byte_offset is unsigned so checking whether it is greater or > > > equal to zero is redundant. > > > > > > Signed-off-by: Christos Gkekas <chris.gekas@gmail.com> > > > > Yep - looks sensible to me. > > > > Signed-off-by: Nick Dyer <nick@shmanahar.org> > > I believe this has been discussed before and Linus told us to keep the > such checks as is: they neatly document the ranges of values, safe in > case we ever change the type of the variables, and do not cost us > anything at execution time. > Fair enough, thanks for your feedback. I believe you are referring to this: https://lkml.org/lkml/2006/11/28/206 Regards, Christos > > > > > > --- > > > drivers/input/touchscreen/atmel_mxt_ts.c | 2 +- > > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > > > diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c > > > index 7659bc4..baafaed 100644 > > > --- a/drivers/input/touchscreen/atmel_mxt_ts.c > > > +++ b/drivers/input/touchscreen/atmel_mxt_ts.c > > > @@ -1356,7 +1356,7 @@ static int mxt_prepare_cfg_mem(struct mxt_data *data, > > > > > > byte_offset = reg + i - cfg_start_ofs; > > > > > > - if (byte_offset >= 0 && byte_offset < config_mem_size) { > > > + if (byte_offset < config_mem_size) { > > > *(config_mem + byte_offset) = val; > > > } else { > > > dev_err(dev, "Bad object: reg:%d, T%d, ofs=%d\n", > > > -- > > > 2.7.4 > > > > > Thanks. > > -- > Dmitry -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c index 7659bc4..baafaed 100644 --- a/drivers/input/touchscreen/atmel_mxt_ts.c +++ b/drivers/input/touchscreen/atmel_mxt_ts.c @@ -1356,7 +1356,7 @@ static int mxt_prepare_cfg_mem(struct mxt_data *data, byte_offset = reg + i - cfg_start_ofs; - if (byte_offset >= 0 && byte_offset < config_mem_size) { + if (byte_offset < config_mem_size) { *(config_mem + byte_offset) = val; } else { dev_err(dev, "Bad object: reg:%d, T%d, ofs=%d\n",
Variable byte_offset is unsigned so checking whether it is greater or equal to zero is redundant. Signed-off-by: Christos Gkekas <chris.gekas@gmail.com> --- drivers/input/touchscreen/atmel_mxt_ts.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)