As the kernel never sets HCR_EL2.EnSCXT, accesses to SCXTNUM_ELx
will trap to EL2. Let's handle that as gracefully as possible
by injecting an UNDEF exception into the guest. This is consistent
with the guest's view of ID_AA64PFR0_EL1.CSV2 being at most 1.
Acked-by: Will Deacon <will@xxxxxxxxxx>
Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
---
arch/arm64/include/asm/sysreg.h | 4 ++++
arch/arm64/kvm/sys_regs.c | 4 ++++
2 files changed, 8 insertions(+)
diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h
index 174817ba119c..e2ef4c2edf06 100644
--- a/arch/arm64/include/asm/sysreg.h
+++ b/arch/arm64/include/asm/sysreg.h
@@ -372,6 +372,8 @@
#define SYS_CONTEXTIDR_EL1 sys_reg(3, 0, 13, 0, 1)
#define SYS_TPIDR_EL1 sys_reg(3, 0, 13, 0, 4)
+#define SYS_SCXTNUM_EL1 sys_reg(3, 0, 13, 0, 7)
+
#define SYS_CNTKCTL_EL1 sys_reg(3, 0, 14, 1, 0)
#define SYS_CCSIDR_EL1 sys_reg(3, 1, 0, 0, 0)
@@ -404,6 +406,8 @@
#define SYS_TPIDR_EL0 sys_reg(3, 3, 13, 0, 2)
#define SYS_TPIDRRO_EL0 sys_reg(3, 3, 13, 0, 3)
+#define SYS_SCXTNUM_EL0 sys_reg(3, 3, 13, 0, 7)
+
/* Definitions for system register interface to AMU for ARMv8.4 onwards */
#define SYS_AM_EL0(crm, op2) sys_reg(3, 3, 13, (crm), (op2))
#define SYS_AMCR_EL0 SYS_AM_EL0(2, 0)
diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index 6155285b2f9b..ea1ef71c1394 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -1640,6 +1640,8 @@ static const struct sys_reg_desc sys_reg_descs[] = {
{ SYS_DESC(SYS_CONTEXTIDR_EL1), access_vm_reg, reset_val, CONTEXTIDR_EL1, 0 },
{ SYS_DESC(SYS_TPIDR_EL1), NULL, reset_unknown, TPIDR_EL1 },
+ { SYS_DESC(SYS_SCXTNUM_EL1), undef_access },
+
{ SYS_DESC(SYS_CNTKCTL_EL1), NULL, reset_val, CNTKCTL_EL1, 0},
{ SYS_DESC(SYS_CCSIDR_EL1), access_ccsidr },
@@ -1668,6 +1670,8 @@ static const struct sys_reg_desc sys_reg_descs[] = {
{ SYS_DESC(SYS_TPIDR_EL0), NULL, reset_unknown, TPIDR_EL0 },
{ SYS_DESC(SYS_TPIDRRO_EL0), NULL, reset_unknown, TPIDRRO_EL0 },
+ { SYS_DESC(SYS_SCXTNUM_EL0), undef_access },
+
{ SYS_DESC(SYS_AMCR_EL0), undef_access },
{ SYS_DESC(SYS_AMCFGR_EL0), undef_access },
{ SYS_DESC(SYS_AMCGCR_EL0), undef_access },
--
2.28.0
