For C language, it treats array parameter as a pointer, so sizeof for an array parameter is equal to sizeof for a pointer, which causes compiler warning (with allmodconfig by gcc 5): CC arch/s390/kernel/asm-offsets.s In file included from include/linux/timex.h:65:0, from include/linux/sched.h:19, from include/linux/kvm_host.h:15, from arch/s390/kernel/asm-offsets.c:10: ./arch/s390/include/asm/timex.h: In function 'get_tod_clock_ext': ./arch/s390/include/asm/timex.h:76:32: warning: 'sizeof' on array function parameter 'clk' will return size of 'char *' [-Wsizeof-array-argument] typedef struct { char _[sizeof(clk)]; } addrtype; ^ Can use macro CLOCK_STORE_SIZE instead of all related hard code numbers, which also can avoid this warning. And also add a tab to CLOCK_TICK_RATE definition to match coding styles. Signed-off-by: Chen Gang <gang.chen.5i5j@xxxxxxxxx> --- arch/s390/hypfs/hypfs_vm.c | 2 +- arch/s390/include/asm/timex.h | 9 +++++---- 2 files changed, 6 insertions(+), 5 deletions(-) diff --git a/arch/s390/hypfs/hypfs_vm.c b/arch/s390/hypfs/hypfs_vm.c index 32040ac..344b622 100644 --- a/arch/s390/hypfs/hypfs_vm.c +++ b/arch/s390/hypfs/hypfs_vm.c @@ -231,7 +231,7 @@ failed: struct dbfs_d2fc_hdr { u64 len; /* Length of d2fc buffer without header */ u16 version; /* Version of header */ - char tod_ext[16]; /* TOD clock for d2fc */ + char tod_ext[CLOCK_STORE_SIZE]; /* TOD clock for d2fc */ u64 count; /* Number of VM guests in d2fc buffer */ char reserved[30]; } __attribute__ ((packed)); diff --git a/arch/s390/include/asm/timex.h b/arch/s390/include/asm/timex.h index 8beee1c..2d2fab6 100644 --- a/arch/s390/include/asm/timex.h +++ b/arch/s390/include/asm/timex.h @@ -67,20 +67,21 @@ static inline void local_tick_enable(unsigned long long comp) set_clock_comparator(S390_lowcore.clock_comparator); } -#define CLOCK_TICK_RATE 1193180 /* Underlying HZ */ +#define CLOCK_TICK_RATE 1193180 /* Underlying HZ */ +#define CLOCK_STORE_SIZE 16 /* store size for clock */ typedef unsigned long long cycles_t; -static inline void get_tod_clock_ext(char clk[16]) +static inline void get_tod_clock_ext(char clk[CLOCK_STORE_SIZE]) { - typedef struct { char _[sizeof(clk)]; } addrtype; + typedef struct { char _[CLOCK_STORE_SIZE]; } addrtype; asm volatile("stcke %0" : "=Q" (*(addrtype *) clk) : : "cc"); } static inline unsigned long long get_tod_clock(void) { - unsigned char clk[16]; + unsigned char clk[CLOCK_STORE_SIZE]; get_tod_clock_ext(clk); return *((unsigned long long *)&clk[1]); } -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-s390" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html