The SBI headers define the Debug Triggers extension and its function IDs, but KVM does not currently allow a VMM to expose DBTR to a guest. Add DBTR to the KVM SBI extension list and forward its calls to userspace through the existing KVM_EXIT_RISCV_SBI path. Keep the extension disabled by default so that userspace must explicitly enable it through the SBI extension ONE_REG interface before running the VCPU. Signed-off-by: Xie Bo --- arch/riscv/include/asm/kvm_vcpu_sbi.h | 1 + arch/riscv/include/uapi/asm/kvm.h | 1 + arch/riscv/kvm/vcpu_sbi.c | 4 ++++ arch/riscv/kvm/vcpu_sbi_forward.c | 7 +++++++ 4 files changed, 13 insertions(+) diff --git a/arch/riscv/include/asm/kvm_vcpu_sbi.h b/arch/riscv/include/asm/kvm_vcpu_sbi.h index c1a7e3b40..53406b02f 100644 --- a/arch/riscv/include/asm/kvm_vcpu_sbi.h +++ b/arch/riscv/include/asm/kvm_vcpu_sbi.h @@ -104,6 +104,7 @@ extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_rfence; extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_srst; extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_hsm; extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_dbcn; +extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_dbtr; extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_susp; extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_sta; extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_fwft; diff --git a/arch/riscv/include/uapi/asm/kvm.h b/arch/riscv/include/uapi/asm/kvm.h index 504e73305..047d82f05 100644 --- a/arch/riscv/include/uapi/asm/kvm.h +++ b/arch/riscv/include/uapi/asm/kvm.h @@ -221,6 +221,7 @@ enum KVM_RISCV_SBI_EXT_ID { KVM_RISCV_SBI_EXT_SUSP, KVM_RISCV_SBI_EXT_FWFT, KVM_RISCV_SBI_EXT_MPXY, + KVM_RISCV_SBI_EXT_DBTR, KVM_RISCV_SBI_EXT_MAX, }; diff --git a/arch/riscv/kvm/vcpu_sbi.c b/arch/riscv/kvm/vcpu_sbi.c index 46ab7b989..ed21239c5 100644 --- a/arch/riscv/kvm/vcpu_sbi.c +++ b/arch/riscv/kvm/vcpu_sbi.c @@ -70,6 +70,10 @@ static const struct kvm_riscv_sbi_extension_entry sbi_ext[] = { .ext_idx = KVM_RISCV_SBI_EXT_DBCN, .ext_ptr = &vcpu_sbi_ext_dbcn, }, + { + .ext_idx = KVM_RISCV_SBI_EXT_DBTR, + .ext_ptr = &vcpu_sbi_ext_dbtr, + }, { .ext_idx = KVM_RISCV_SBI_EXT_SUSP, .ext_ptr = &vcpu_sbi_ext_susp, diff --git a/arch/riscv/kvm/vcpu_sbi_forward.c b/arch/riscv/kvm/vcpu_sbi_forward.c index 5a3c75eb2..8ac31b53f 100644 --- a/arch/riscv/kvm/vcpu_sbi_forward.c +++ b/arch/riscv/kvm/vcpu_sbi_forward.c @@ -26,6 +26,13 @@ const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_dbcn = { .handler = kvm_riscv_vcpu_sbi_forward_handler, }; +const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_dbtr = { + .extid_start = SBI_EXT_DBTR, + .extid_end = SBI_EXT_DBTR, + .default_disabled = true, + .handler = kvm_riscv_vcpu_sbi_forward_handler, +}; + const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_mpxy = { .extid_start = SBI_EXT_MPXY, .extid_end = SBI_EXT_MPXY, base-commit: b95f03f04d475aa6719d15a636ddf32222d55657 -- 2.54.0