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> > > > + /* Keep the pre-DS 5-bit truncation when scale > 31 */ > > cmd->data[0] = orig_data0 | > > FIELD_PREP(CMDQ_TLBI_0_NUM, num - 1) | > > - FIELD_PREP(CMDQ_TLBI_0_SCALE, scale); > > + FIELD_PREP(CMDQ_TLBI_0_SCALE, scale & 0x1f); > > Nit: Not sure what the convention is for these things, but this cap for > host is temporary as Jason's iommupt series expands the scale when DS=1. > I'm not sure if we should note a TODO here or just leave it be for now? That kind of looks like an existing bug.. Technically it looks like a very large invalidation could be created that can overflow scale and break this algorithm. Adding the 0x1f at least keeps this as 'no change': broken under invalidation, but not broken malformed command.. Let's just leave it like above, my series fixes that little miss too: scale = fls64((num_tg - 1) / 32); if (scale > scale_max) { /* * Range too large for a single command, use full invalidation. */ tlbi->range.use_full_inv = true; return; } Jason