diff options
-rw-r--r-- | arch/arm64/kvm/sys_regs.c | 16 | ||||
-rw-r--r-- | tools/testing/selftests/kvm/aarch64/set_id_regs.c | 2 |
2 files changed, 17 insertions, 1 deletions
diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index c90324060436..5a49e8331fbf 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -2376,7 +2376,21 @@ static const struct sys_reg_desc sys_reg_descs[] = { .get_user = get_id_reg, .set_user = set_id_aa64dfr0_el1, .reset = read_sanitised_id_aa64dfr0_el1, - .val = ID_AA64DFR0_EL1_PMUVer_MASK | + /* + * Prior to FEAT_Debugv8.9, the architecture defines context-aware + * breakpoints (CTX_CMPs) as the highest numbered breakpoints (BRPs). + * KVM does not trap + emulate the breakpoint registers, and as such + * cannot support a layout that misaligns with the underlying hardware. + * While it may be possible to describe a subset that aligns with + * hardware, just prevent changes to BRPs and CTX_CMPs altogether for + * simplicity. + * + * See DDI0487K.a, section D2.8.3 Breakpoint types and linking + * of breakpoints for more details. + */ + .val = ID_AA64DFR0_EL1_DoubleLock_MASK | + ID_AA64DFR0_EL1_WRPs_MASK | + ID_AA64DFR0_EL1_PMUVer_MASK | ID_AA64DFR0_EL1_DebugVer_MASK, }, ID_SANITISED(ID_AA64DFR1_EL1), ID_UNALLOCATED(5,2), diff --git a/tools/testing/selftests/kvm/aarch64/set_id_regs.c b/tools/testing/selftests/kvm/aarch64/set_id_regs.c index d20981663831..6edc5412abe8 100644 --- a/tools/testing/selftests/kvm/aarch64/set_id_regs.c +++ b/tools/testing/selftests/kvm/aarch64/set_id_regs.c @@ -68,6 +68,8 @@ struct test_feature_reg { } static const struct reg_ftr_bits ftr_id_aa64dfr0_el1[] = { + S_REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64DFR0_EL1, DoubleLock, 0), + REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64DFR0_EL1, WRPs, 0), S_REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64DFR0_EL1, PMUVer, 0), REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64DFR0_EL1, DebugVer, ID_AA64DFR0_EL1_DebugVer_IMP), REG_FTR_END, |