On 05/03/2026 11:01 pm, Andrew Cooper wrote: > On 05/03/2026 7:57 pm, Ayan Kumar Halder wrote: >> The lr_mask bitmap tracks which List Registers (LRs) are in use for >> virtual interrupt injection. Previously, lr_mask always used uint64_t >> (8 bytes) to support the maximum number of LRs across both GIC versions. >> >> However, GICv2 and GICv3 have different hardware limits: >> - GICv3: ICH_VTR_EL2[3:0] encodes LR count -> max 16 LRs (4 bits) >> - GICv2: GICH_VTR[5:0] encodes LR count -> max 64 LRs (6 bits) >> >> This patch introduces conditional compilation to optimize lr_mask size: >> - CONFIG_GICV3=y: Use uint16_t (2 bytes) - sufficient for 16 LRs >> - CONFIG_GICV3=n: Use uint64_t (8 bytes) - required for 64 LRs >> >> With this, parameter 'lr' in gicv3_ich_read_lr(), gicv3_ich_write_lr() >> cannot have a value > 15. Thus, it should not possible to hit the >> BUG() in the default case. >> >> Signed-off-by: Ayan Kumar Halder <[email protected]> > What does this actually get you? > > Because it doesn't actually eliminate the BUG()s you reference. > > If you really want to go ahead with this patch, then make a lr_mask_t > or the right type and don't double-code everything.
Also, this creates an Out-of-Bounds read in vgic_sync_from_lrs() amongst others. ~Andrew
