The hart bit setting is different with Linux AIA driver[1] when the number of hart is power of 2. For example, when the guest has 4 harts, the estimated result of AIA driver is 2, whereas we pass 3 to RISC-V/KVM. Since only 2 bits are needed to represent 4 harts, update the formula to get the accurate result. [1] https://lore.kernel.org/all/20240307140307.646078-1-apatel@xxxxxxxxxxxxxxxx/ Signed-off-by: Yong-Xuan Wang <yongxuan.wang@xxxxxxxxxx> --- riscv/aia.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/riscv/aia.c b/riscv/aia.c index fe9399a8ffc1..21d9704145d0 100644 --- a/riscv/aia.c +++ b/riscv/aia.c @@ -164,7 +164,7 @@ static int aia__init(struct kvm *kvm) ret = ioctl(aia_fd, KVM_SET_DEVICE_ATTR, &aia_nr_sources_attr); if (ret) return ret; - aia_hart_bits = fls_long(kvm->nrcpus); + aia_hart_bits = fls_long(kvm->nrcpus - 1); ret = ioctl(aia_fd, KVM_SET_DEVICE_ATTR, &aia_hart_bits_attr); if (ret) return ret; -- 2.17.1
