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

[Yang Shi]

On 10/1/24 12:46 PM, Jason Gunthorpe wrote:
> On Tue, Oct 01, 2024 at 12:38:56PM -0700, Yang Shi wrote:
> > On 10/1/24 12:18 PM, Jason Gunthorpe wrote:
> > > On Tue, Oct 01, 2024 at 12:09:03PM -0700, Yang Shi wrote:
> > > > > Also, there are other places doing "1 << smmu->sid_bits", e.g.
> > > > > arm_smmu_init_strtab_linear().
> > > > The disassembly shows it uses "sbfiz x21, x20, 6, 32" instead of lsl. 1UL
> > > > should be used if we want to take extra caution and don't prefer rely on
> > > > compiler.
> > > Still, we should be fixing them all if sid_bits == 32, all those
> > > shifts should be throwing a UBSAN error. It would be crazy to have a
> > OK, will cover this is v2.
> Maybe just make a little inline function to do this math and remove
> the repated open coding? Then the types can be right, etc.

Fine to me.

> Jason