Messages in this thread Patch in this message | ![/](/images/icornerl.gif) | | From | Qian Cai <> | Subject | [PATCH] arm64/prefetch: fix a -Wtype-limits warning | Date | Fri, 2 Aug 2019 17:08:04 -0400 |
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The commit d5370f754875 ("arm64: prefetch: add alternative pattern for CPUs without a prefetcher") introduced MIDR_IS_CPU_MODEL_RANGE() to be used in has_no_hw_prefetch() with rv_min=0 which generates a compilation warning from GCC,
In file included from ./arch/arm64/include/asm/cache.h:8, from ./include/linux/cache.h:6, from ./include/linux/printk.h:9, from ./include/linux/kernel.h:15, from ./include/linux/cpumask.h:10, from arch/arm64/kernel/cpufeature.c:11: arch/arm64/kernel/cpufeature.c: In function 'has_no_hw_prefetch': ./arch/arm64/include/asm/cputype.h:59:26: warning: comparison of unsigned expression >= 0 is always true [-Wtype-limits] _model == (model) && rv >= (rv_min) && rv <= (rv_max); \ ^~ arch/arm64/kernel/cpufeature.c:889:9: note: in expansion of macro 'MIDR_IS_CPU_MODEL_RANGE' return MIDR_IS_CPU_MODEL_RANGE(midr, MIDR_THUNDERX, ^~~~~~~~~~~~~~~~~~~~~~~
Fix it by making rv_min=1.
Signed-off-by: Qian Cai <cai@lca.pw> --- arch/arm64/kernel/cpufeature.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index f29f36a65175..7d15cf6d62c1 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -883,7 +883,7 @@ static bool has_no_hw_prefetch(const struct arm64_cpu_capabilities *entry, int _ /* Cavium ThunderX pass 1.x and 2.x */ return MIDR_IS_CPU_MODEL_RANGE(midr, MIDR_THUNDERX, - MIDR_CPU_VAR_REV(0, 0), + MIDR_CPU_VAR_REV(0, 1), MIDR_CPU_VAR_REV(1, MIDR_REVISION_MASK)); } -- 1.8.3.1
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