Any valid implementation of the architecture should generate an
undefined exception for writes to a read-only register, such as
OSLSR_EL1. Nonetheless, the KVM handler actually implements write-ignore
behavior.
Align the trap handler for OSLSR_EL1 with hardware behavior. If such a
write ever traps to EL2, inject an undef into the guest and print a
warning.
Reviewed-by: Reiji Watanabe <reijiw@xxxxxxxxxx>
Signed-off-by: Oliver Upton <oupton@xxxxxxxxxx>
---
arch/arm64/kvm/sys_regs.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index e3ec1a44f94d..11b4212c2036 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -292,7 +292,7 @@ static bool trap_oslsr_el1(struct kvm_vcpu *vcpu,
const struct sys_reg_desc *r)
{
if (p->is_write) {
- return ignore_write(vcpu, p);
+ return write_to_read_only(vcpu, p, r);
} else {
p->regval = (1 << 3);
return true;
--
2.34.0.rc2.393.gf8c9666880-goog
