On 09/05/2019 04:13:55+0200, Nicholas Mc Guire wrote: > Converting from hardware to host endiannes was done using reassignment > to the same variable which makes sparse unhappy as it can not verify > the endiannes handling properly. To allow sparse to verify endiannes > handling an explicit __le32 is introduced. Note that this patch does > not change the generated binary (x86_64 and ppc64 binary diff). > > Signed-off-by: Nicholas Mc Guire <hofrat@xxxxxxxxx> > --- > > Problem located by an experimental coccinelle script to locate > patters that make sparse unhappy (false positives): > > on little-endian x86_64 sparse complains about: > drivers/rtc/rtc-ds2404.c:187:16: warning: cast to restricted __le32 > on big-endian ppc64 sparse complains about > drivers/rtc/rtc-ds2404.c:187:16: warning: cast to restricted __le32 > drivers/rtc/rtc-ds2404.c:187:16: warning: cast to restricted __le32 > drivers/rtc/rtc-ds2404.c:187:16: warning: cast to restricted __le32 > drivers/rtc/rtc-ds2404.c:187:16: warning: cast to restricted __le32 > drivers/rtc/rtc-ds2404.c:187:16: warning: cast to restricted __le32 > drivers/rtc/rtc-ds2404.c:187:16: warning: cast to restricted __le32 > > Patch was compiletested with: > x86_64_defconfig + RTC_DRV_DS2404=m > ppc64_defconfig + RTC_DRV_DS2404=m > > in both cases applying the patch has no impact on the generated binary. > > Patch is against 5.1 (localversion-next is next-20190508) > > drivers/rtc/rtc-ds2404.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > Applied, thanks. -- Alexandre Belloni, Bootlin Embedded Linux and Kernel engineering https://bootlin.com
