Re: [PATCH] iommu/arm-smmu-v3: Fix L1 stream table index calculation for AmpereOne

[Nicolin Chen]

On Tue, Oct 01, 2024 at 11:03:46AM -0700, Yang Shi wrote:
> Using 64 bit immediate when doing shift can solve the problem.  The
> disssembly after the fix looks like:

[...]

>         unsigned int last_sid_idx =
> -               arm_smmu_strtab_l1_idx((1 << smmu->sid_bits) - 1);
> +               arm_smmu_strtab_l1_idx((1UL << smmu->sid_bits) - 1);

Could a 32-bit build be a corner case where UL is no longer a
"64 bit" stated in the commit message?

Also, there are other places doing "1 << smmu->sid_bits", e.g.
arm_smmu_init_strtab_linear().

Then, can ssid_bits/s1cdmax be a concern similarly?

Thanks
Nicolin