4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Matthias Kaehlcke <mka@xxxxxxxxxxxx> commit 0773cea37470f8e080c510fe720fc356cf35df3a upstream Besides reusing existing code this removes the special case handling for 64-bit masks, which causes clang to raise a shift count overflow warning due to https://bugs.llvm.org//show_bug.cgi?id=10030. Suggested-by: Dmitry Torokhov <dtor@xxxxxxxxxxxx> Signed-off-by: Matthias Kaehlcke <mka@xxxxxxxxxxxx> Cc: Grant Grundler <grundler@xxxxxxxxxxxx> Cc: Greg Hackmann <ghackmann@xxxxxxxxxx> Cc: Michael Davidson <md@xxxxxxxxxx> Cc: John Stultz <john.stultz@xxxxxxxxxx> Link: http://lkml.kernel.org/r/20170418233037.70990-1-mka@xxxxxxxxxxxx Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> [nc: cycle_t wasn't eliminated until commit a5a1d1c2914b ("clocksource: Use a plain u64 instead of cycle_t") in v4.10] Signed-off-by: Nathan Chancellor <natechancellor@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- include/linux/clocksource.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/include/linux/clocksource.h +++ b/include/linux/clocksource.h @@ -117,7 +117,7 @@ struct clocksource { #define CLOCK_SOURCE_RESELECT 0x100 /* simplify initialization of mask field */ -#define CLOCKSOURCE_MASK(bits) (cycle_t)((bits) < 64 ? ((1ULL<<(bits))-1) : -1) +#define CLOCKSOURCE_MASK(bits) GENMASK_ULL((bits) - 1, 0) static inline u32 clocksource_freq2mult(u32 freq, u32 shift_constant, u64 from) {
