When the maximum hart number within groups is 1, hart-index-bit is set to 0. Consequently, there is no need to restore the hart ID from IMSIC addresses and hart-index-bit settings. Currently, QEMU and kvmtool do not pass correct hart-index-bit values when the maximum hart number is a power of 2, thereby avoiding this issue. Corresponding patches for QEMU and kvmtool will also be dispatched. Fixes: 89d01306e34d ("RISC-V: KVM: Implement device interface for AIA irqchip") Signed-off-by: Yong-Xuan Wang <yongxuan.wang@xxxxxxxxxx> --- arch/riscv/kvm/aia_device.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/arch/riscv/kvm/aia_device.c b/arch/riscv/kvm/aia_device.c index 0eb689351b7d..5cd407c6a8e4 100644 --- a/arch/riscv/kvm/aia_device.c +++ b/arch/riscv/kvm/aia_device.c @@ -237,10 +237,11 @@ static gpa_t aia_imsic_ppn(struct kvm_aia *aia, gpa_t addr) static u32 aia_imsic_hart_index(struct kvm_aia *aia, gpa_t addr) { - u32 hart, group = 0; + u32 hart = 0, group = 0; - hart = (addr >> (aia->nr_guest_bits + IMSIC_MMIO_PAGE_SHIFT)) & - GENMASK_ULL(aia->nr_hart_bits - 1, 0); + if (aia->nr_hart_bits) + hart = (addr >> (aia->nr_guest_bits + IMSIC_MMIO_PAGE_SHIFT)) & + GENMASK_ULL(aia->nr_hart_bits - 1, 0); if (aia->nr_group_bits) group = (addr >> aia->nr_group_shift) & GENMASK_ULL(aia->nr_group_bits - 1, 0); -- 2.17.1