Re: [PATCH v2] arm64/cache: fix -Woverride-init compiler warnings

From: Will Deacon
Date: Wed Aug 07 2019 - 06:57:00 EST


On Tue, Aug 06, 2019 at 03:34:34PM -0400, Qian Cai wrote:
> diff --git a/arch/arm64/kernel/cpuinfo.c b/arch/arm64/kernel/cpuinfo.c
> index 876055e37352..a0c495a3f4fd 100644
> --- a/arch/arm64/kernel/cpuinfo.c
> +++ b/arch/arm64/kernel/cpuinfo.c
> @@ -34,10 +34,7 @@ DEFINE_PER_CPU(struct cpuinfo_arm64, cpu_data);
> static struct cpuinfo_arm64 boot_cpu_data;
>
> static char *icache_policy_str[] = {
> - [0 ... ICACHE_POLICY_PIPT] = "RESERVED/UNKNOWN",
> - [ICACHE_POLICY_VIPT] = "VIPT",
> - [ICACHE_POLICY_PIPT] = "PIPT",
> - [ICACHE_POLICY_VPIPT] = "VPIPT",
> + [0 ... ICACHE_POLICY_PIPT] = "RESERVED/UNKNOWN"
> };
>
> unsigned long __icache_flags;
> @@ -310,13 +307,16 @@ static void cpuinfo_detect_icache_policy(struct cpuinfo_arm64 *info)
>
> switch (l1ip) {
> case ICACHE_POLICY_PIPT:
> + icache_policy_str[ICACHE_POLICY_PIPT] = "PIPT";
> break;
> case ICACHE_POLICY_VPIPT:
> + icache_policy_str[ICACHE_POLICY_VPIPT] = "VPIPT";
> set_bit(ICACHEF_VPIPT, &__icache_flags);
> break;
> default:
> /* Fallthrough */
> case ICACHE_POLICY_VIPT:
> + icache_policy_str[ICACHE_POLICY_VIPT] = "VIPT";
> /* Assume aliasing */
> set_bit(ICACHEF_ALIASING, &__icache_flags);

I still think this is worse than the code in mainline. I don't think
-Woverride-init should warn when overriding a field from a GCC range
designated initialiser, since it makes them considerably less useful
imo.

Will