Re: [PATCH V2] arm64/cpufeature: Add get_arm64_ftr_reg_nowarn()

Catalin Marinas
2020-05-26T15:01:46Z

On Tue, May 26, 2020 at 07:09:13PM +0530, Anshuman Khandual wrote:
> @@ -632,8 +654,6 @@ static void __init init_cpu_ftr_reg(u32 sys_reg, u64 new)
> const struct arm64_ftr_bits *ftrp;
> struct arm64_ftr_reg *reg = get_arm64_ftr_reg(sys_reg);
>
> - BUG_ON(!reg);
> -
> for (ftrp = reg->ftr_bits; ftrp->width; ftrp++) {
> u64 ftr_mask = arm64_ftr_mask(ftrp);
> s64 ftr_new = arm64_ftr_value(ftrp, new);
> @@ -762,7 +782,6 @@ static int check_update_ftr_reg(u32 sys_id, int cpu, u64 val, u64 boot)
> {
> struct arm64_ftr_reg *regp = get_arm64_ftr_reg(sys_id);
>
> - BUG_ON(!regp);
> update_cpu_ftr_reg(regp, val);
> if ((boot & regp->strict_mask) == (val & regp->strict_mask))
> return 0;
> @@ -776,9 +795,6 @@ static void relax_cpu_ftr_reg(u32 sys_id, int field)
> const struct arm64_ftr_bits *ftrp;
> struct arm64_ftr_reg *regp = get_arm64_ftr_reg(sys_id);
>
> - if (WARN_ON(!regp))
> - return;

I think Will wanted an early return in all these functions not just
removing the BUG_ON(). I'll let him clarify.

--
Catalin