[PATCH v9 05/11] KVM: arm64: Enable writable for ID_AA64DFR0_EL1 and ID_DFR0_EL1

[Jing Zhang]

All valid fields in ID_AA64DFR0_EL1 and ID_DFR0_EL1 are writable
from userspace with this change.
RES0 fields and those fields hidden by KVM are not writable.

Signed-off-by: Jing Zhang <jingzhangos at google.com>
---
 arch/arm64/kvm/sys_regs.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index afade7186675..20fc38bad4e8 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -1931,6 +1931,8 @@ static bool access_spsr(struct kvm_vcpu *vcpu,
 	return true;
 }
 
+#define ID_AA64DFR0_EL1_RES0_MASK (GENMASK(59, 56) | GENMASK(27, 24) | GENMASK(19, 16))
+
 /*
  * Architected system registers.
  * Important: Must be sorted ascending by Op0, Op1, CRn, CRm, Op2
@@ -2006,7 +2008,7 @@ static const struct sys_reg_desc sys_reg_descs[] = {
 	  .set_user = set_id_dfr0_el1,
 	  .visibility = aa32_id_visibility,
 	  .reset = read_sanitised_id_dfr0_el1,
-	  .val = ID_DFR0_EL1_PerfMon_MASK, },
+	  .val = GENMASK(31, 0), },
 	ID_HIDDEN(ID_AFR0_EL1),
 	AA32_ID_SANITISED(ID_MMFR0_EL1),
 	AA32_ID_SANITISED(ID_MMFR1_EL1),
@@ -2055,7 +2057,7 @@ 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, },
+	  .val = ~(ID_AA64DFR0_EL1_PMSVer_MASK | ID_AA64DFR0_EL1_RES0_MASK), },
 	ID_SANITISED(ID_AA64DFR1_EL1),
 	ID_UNALLOCATED(5,2),
 	ID_UNALLOCATED(5,3),
-- 
2.42.0.rc1.204.g551eb34607-goog